diff --git a/.github/actions/ollama/action.yml b/.github/actions/ollama/action.yml
index 9af8b4fa0..841890b13 100644
--- a/.github/actions/ollama/action.yml
+++ b/.github/actions/ollama/action.yml
@@ -20,6 +20,7 @@ runs:
       run: |
         ollama pull granite3.2:2b
         ollama pull granite3.2:8b
+        ollama pull granite3.3:2b
         ollama pull granite3.3:8b
         ollama pull mxbai-embed-large
         ollama list
diff --git a/examples/aggregators/contribute_in_file.pdl b/examples/aggregators/contribute_in_file.pdl
new file mode 100644
index 000000000..4cb7bbcb4
--- /dev/null
+++ b/examples/aggregators/contribute_in_file.pdl
@@ -0,0 +1,20 @@
+defs:
+  log:
+    aggregator: 
+      file: /tmp/log.txt
+text:
+- Hello
+- model: ollama_chat/granite3.3:2b
+  parameters:
+    temperature: 0
+  contribute: [ result, context, log ]
+- nice to meet you.
+- model: ollama_chat/granite3.3:2b
+  parameters:
+    temperature: 0
+  modelResponse: raw_response
+  contribute:
+    - result
+    - log:
+        value: ${raw_response}
+- Bye
diff --git a/examples/aggregators/contribute_in_stderr.pdl b/examples/aggregators/contribute_in_stderr.pdl
new file mode 100644
index 000000000..83faf41de
--- /dev/null
+++ b/examples/aggregators/contribute_in_stderr.pdl
@@ -0,0 +1,10 @@
+text:
+- Hello
+- text: Before model call
+  contribute: [ stderr ]
+- model: ollama_chat/granite3.3:2b
+  parameters:
+    temperature: 0
+- contribute:
+    - stderr:
+        value: After model call
diff --git a/examples/aggregators/contribute_in_stdout.pdl b/examples/aggregators/contribute_in_stdout.pdl
new file mode 100644
index 000000000..fed5cfc47
--- /dev/null
+++ b/examples/aggregators/contribute_in_stdout.pdl
@@ -0,0 +1,10 @@
+text:
+- Hello
+- text: Before model call
+  contribute: [ stdout ]
+- model: ollama_chat/granite3.3:2b
+  parameters:
+    temperature: 0
+- contribute:
+    - stdout:
+        value: After model call
diff --git a/pdl-live-react/src/pdl_ast.d.ts b/pdl-live-react/src/pdl_ast.d.ts
index f15502b41..332b3b437 100644
--- a/pdl-live-react/src/pdl_ast.d.ts
+++ b/pdl-live-react/src/pdl_ast.d.ts
@@ -32,6 +32,7 @@ export type Program =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -167,6 +168,11 @@ export type Description19 = string | null
  *
  */
 export type Description20 = string | null
+/**
+ * Documentation associated to the block.
+ *
+ */
+export type Description21 = string | null
 /**
  * Name of the variable used to store the result of the execution of the block.
  *
@@ -175,16 +181,14 @@ export type Def = string | null
 /**
  * Values allowed in the `contribute` field.
  */
-export type ContributeTarget = "result" | "context"
-export type Value = LocalizedExpression | unknown[] | string
-export type Path = string[]
-export type File = string
+export type ContributeTarget = "result" | "context" | "stdout" | "stderr"
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
 export type Contribute = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -197,7 +201,7 @@ export type Parser =
   | PdlParser
   | RegexParser
   | null
-export type Description21 = string | null
+export type Description22 = string | null
 export type Pdl =
   | boolean
   | number
@@ -221,10 +225,11 @@ export type Pdl =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
-export type Description22 = string | null
+export type Description23 = string | null
 export type Regex = string
 export type Mode = "search" | "match" | "fullmatch" | "split" | "findall"
 /**
@@ -254,6 +259,7 @@ export type Fallback =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -287,6 +293,8 @@ export type PdlContext =
  *
  */
 export type PdlId = string | null
+export type Path = string[]
+export type File = string
 export type StartNanos = number | null
 export type EndNanos = number | null
 export type FirstUseNanos = number | null
@@ -304,6 +312,7 @@ export type Def1 = string | null
  */
 export type Contribute1 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -343,6 +352,7 @@ export type Fallback1 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -410,6 +420,7 @@ export type Program1 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -424,6 +435,7 @@ export type Def2 = string | null
  */
 export type Contribute2 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -463,6 +475,7 @@ export type Fallback2 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -497,7 +510,124 @@ export type PdlContext2 =
  */
 export type PdlId2 = string | null
 export type PdlIsLeaf2 = true
-export type Kind2 = "import"
+export type Kind2 = "aggregator"
+export type Aggregator = "context" | FileAggregatorConfig
+/**
+ * Documentation associated to the aggregator config.
+ *
+ */
+export type Description24 = string | null
+/**
+ * Name of the file to which contribute.
+ */
+export type File1 = LocalizedExpression | string
+/**
+ * File opening mode.
+ */
+export type Mode1 = LocalizedExpression | string
+/**
+ * File encoding.
+ */
+export type Encoding = LocalizedExpression | string | null
+/**
+ * Prefix to the contributed value.
+ */
+export type Prefix = LocalizedExpression | string
+/**
+ * Suffix to the contributed value.
+ */
+export type Suffix = LocalizedExpression | string
+/**
+ * Whether to forcibly flush the stream.
+ */
+export type Flush = LocalizedExpression | boolean | string
+/**
+ * Name of the variable used to store the result of the execution of the block.
+ *
+ */
+export type Def3 = string | null
+/**
+ * Indicate if the block contributes to the result and background context.
+ *
+ */
+export type Contribute3 = (
+  | ContributeTarget
+  | string
+  | {
+      [k: string]: ContributeValue
+    }
+)[]
+/**
+ * Parser to use to construct a value out of a string result.
+ */
+export type Parser3 =
+  | ("json" | "jsonl" | "yaml")
+  | PdlParser
+  | RegexParser
+  | null
+/**
+ * Block to execute in case of error.
+ *
+ */
+export type Fallback3 =
+  | boolean
+  | number
+  | string
+  | FunctionBlock
+  | CallBlock
+  | LitellmModelBlock
+  | GraniteioModelBlock
+  | CodeBlock
+  | ArgsBlock
+  | GetBlock
+  | DataBlock
+  | IfBlock
+  | MatchBlock
+  | RepeatBlock
+  | TextBlock
+  | LastOfBlock
+  | ArrayBlock
+  | ObjectBlock
+  | MessageBlock
+  | ReadBlock
+  | IncludeBlock
+  | ImportBlock
+  | AggregatorBlock
+  | ErrorBlock
+  | EmptyBlock
+  | null
+/**
+ * The maximum number of times to retry when an error occurs within a block.
+ *
+ */
+export type Retry3 = number | null
+/**
+ * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
+ *
+ */
+export type TraceErrorOnRetry3 = boolean | string | null
+/**
+ * Role associated to the block and sub-blocks.
+ * Typical roles are `system`, `user`, and `assistant`,
+ * but there may be other roles such as `available_tools`.
+ */
+export type Role3 = string | null
+/**
+ * Current context
+ *
+ */
+export type PdlContext3 =
+  | {
+      [k: string]: unknown
+    }[]
+  | null
+/**
+ * Unique identifier for this block
+ *
+ */
+export type PdlId3 = string | null
+export type PdlIsLeaf3 = true
+export type Kind3 = "import"
 /**
  * Name of the file to import.
  *
@@ -526,6 +656,7 @@ export type PdlTrace =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -533,13 +664,14 @@ export type PdlTrace =
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def3 = string | null
+export type Def4 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute3 = (
+export type Contribute4 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -547,7 +679,7 @@ export type Contribute3 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser3 =
+export type Parser4 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -556,7 +688,7 @@ export type Parser3 =
  * Block to execute in case of error.
  *
  */
-export type Fallback3 =
+export type Fallback4 =
   | boolean
   | number
   | string
@@ -579,6 +711,7 @@ export type Fallback3 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -586,23 +719,23 @@ export type Fallback3 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry3 = number | null
+export type Retry4 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry3 = boolean | string | null
+export type TraceErrorOnRetry4 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role3 = string | null
+export type Role4 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext3 =
+export type PdlContext4 =
   | {
       [k: string]: unknown
     }[]
@@ -611,10 +744,10 @@ export type PdlContext3 =
  * Unique identifier for this block
  *
  */
-export type PdlId3 = string | null
-export type PdlIsLeaf3 = false
+export type PdlId4 = string | null
+export type PdlIsLeaf4 = false
 export type IndependentEnum = "independent" | "dependent"
-export type Kind3 = "include"
+export type Kind4 = "include"
 /**
  * Name of the file to include.
  *
@@ -643,6 +776,7 @@ export type PdlTrace1 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -650,13 +784,14 @@ export type PdlTrace1 =
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def4 = string | null
+export type Def5 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute4 = (
+export type Contribute5 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -664,7 +799,7 @@ export type Contribute4 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser4 =
+export type Parser5 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -673,7 +808,7 @@ export type Parser4 =
  * Block to execute in case of error.
  *
  */
-export type Fallback4 =
+export type Fallback5 =
   | boolean
   | number
   | string
@@ -696,6 +831,7 @@ export type Fallback4 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -703,23 +839,23 @@ export type Fallback4 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry4 = number | null
+export type Retry5 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry4 = boolean | string | null
+export type TraceErrorOnRetry5 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role4 = string | null
+export type Role5 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext4 =
+export type PdlContext5 =
   | {
       [k: string]: unknown
     }[]
@@ -728,9 +864,9 @@ export type PdlContext4 =
  * Unique identifier for this block
  *
  */
-export type PdlId4 = string | null
-export type PdlIsLeaf4 = true
-export type Kind4 = "read"
+export type PdlId5 = string | null
+export type PdlIsLeaf5 = true
+export type Kind5 = "read"
 /**
  * Name of the file to read. If `None`, read the standard input.
  *
@@ -750,13 +886,14 @@ export type Multiline = boolean
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def5 = string | null
+export type Def6 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute5 = (
+export type Contribute6 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -764,7 +901,7 @@ export type Contribute5 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser5 =
+export type Parser6 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -773,7 +910,7 @@ export type Parser5 =
  * Block to execute in case of error.
  *
  */
-export type Fallback5 =
+export type Fallback6 =
   | boolean
   | number
   | string
@@ -796,6 +933,7 @@ export type Fallback5 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -803,23 +941,23 @@ export type Fallback5 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry5 = number | null
+export type Retry6 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry5 = boolean | string | null
+export type TraceErrorOnRetry6 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role5 = string | null
+export type Role6 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext5 =
+export type PdlContext6 =
   | {
       [k: string]: unknown
     }[]
@@ -828,9 +966,9 @@ export type PdlContext5 =
  * Unique identifier for this block
  *
  */
-export type PdlId5 = string | null
-export type PdlIsLeaf5 = true
-export type Kind5 = "message"
+export type PdlId6 = string | null
+export type PdlIsLeaf6 = true
+export type Kind6 = "message"
 /**
  * Content of the message.
  */
@@ -857,6 +995,7 @@ export type Content =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -872,13 +1011,14 @@ export type ToolCallId = LocalizedExpression | string | null
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def6 = string | null
+export type Def7 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute6 = (
+export type Contribute7 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -886,7 +1026,7 @@ export type Contribute6 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser6 =
+export type Parser7 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -895,7 +1035,7 @@ export type Parser6 =
  * Block to execute in case of error.
  *
  */
-export type Fallback6 =
+export type Fallback7 =
   | boolean
   | number
   | string
@@ -918,6 +1058,7 @@ export type Fallback6 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -925,23 +1066,23 @@ export type Fallback6 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry6 = number | null
+export type Retry7 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry6 = boolean | string | null
+export type TraceErrorOnRetry7 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role6 = string | null
+export type Role7 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext6 =
+export type PdlContext7 =
   | {
       [k: string]: unknown
     }[]
@@ -950,10 +1091,10 @@ export type PdlContext6 =
  * Unique identifier for this block
  *
  */
-export type PdlId6 = string | null
-export type PdlIsLeaf6 = false
+export type PdlId7 = string | null
+export type PdlIsLeaf7 = false
 export type IndependentEnum1 = "independent" | "dependent"
-export type Kind6 = "object"
+export type Kind7 = "object"
 export type Object1 =
   | {
       [k: string]:
@@ -979,6 +1120,7 @@ export type Object1 =
         | ReadBlock
         | IncludeBlock
         | ImportBlock
+        | AggregatorBlock
         | ErrorBlock
         | EmptyBlock
         | null
@@ -1006,6 +1148,7 @@ export type Object1 =
       | ReadBlock
       | IncludeBlock
       | ImportBlock
+      | AggregatorBlock
       | ErrorBlock
       | EmptyBlock
       | null
@@ -1014,13 +1157,14 @@ export type Object1 =
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def7 = string | null
+export type Def8 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute7 = (
+export type Contribute8 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -1028,7 +1172,7 @@ export type Contribute7 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser7 =
+export type Parser8 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -1037,7 +1181,7 @@ export type Parser7 =
  * Block to execute in case of error.
  *
  */
-export type Fallback7 =
+export type Fallback8 =
   | boolean
   | number
   | string
@@ -1060,6 +1204,7 @@ export type Fallback7 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1067,23 +1212,23 @@ export type Fallback7 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry7 = number | null
+export type Retry8 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry7 = boolean | string | null
+export type TraceErrorOnRetry8 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role7 = string | null
+export type Role8 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext7 =
+export type PdlContext8 =
   | {
       [k: string]: unknown
     }[]
@@ -1092,10 +1237,10 @@ export type PdlContext7 =
  * Unique identifier for this block
  *
  */
-export type PdlId7 = string | null
-export type PdlIsLeaf7 = false
+export type PdlId8 = string | null
+export type PdlIsLeaf8 = false
 export type IndependentEnum2 = "independent" | "dependent"
-export type Kind7 = "array"
+export type Kind8 = "array"
 /**
  * Elements of the array.
  */
@@ -1122,6 +1267,7 @@ export type Array = (
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1130,13 +1276,14 @@ export type Array = (
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def8 = string | null
+export type Def9 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute8 = (
+export type Contribute9 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -1144,7 +1291,7 @@ export type Contribute8 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser8 =
+export type Parser9 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -1153,7 +1300,7 @@ export type Parser8 =
  * Block to execute in case of error.
  *
  */
-export type Fallback8 =
+export type Fallback9 =
   | boolean
   | number
   | string
@@ -1176,6 +1323,7 @@ export type Fallback8 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1183,23 +1331,23 @@ export type Fallback8 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry8 = number | null
+export type Retry9 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry8 = boolean | string | null
+export type TraceErrorOnRetry9 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role8 = string | null
+export type Role9 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext8 =
+export type PdlContext9 =
   | {
       [k: string]: unknown
     }[]
@@ -1208,10 +1356,10 @@ export type PdlContext8 =
  * Unique identifier for this block
  *
  */
-export type PdlId8 = string | null
-export type PdlIsLeaf8 = false
+export type PdlId9 = string | null
+export type PdlIsLeaf9 = false
 export type IndependentEnum3 = "independent" | "dependent"
-export type Kind8 = "lastOf"
+export type Kind9 = "lastOf"
 /**
  * Sequence of blocks to execute.
  */
@@ -1238,6 +1386,7 @@ export type Lastof = (
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1246,13 +1395,14 @@ export type Lastof = (
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def9 = string | null
+export type Def10 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute9 = (
+export type Contribute10 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -1260,7 +1410,7 @@ export type Contribute9 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser9 =
+export type Parser10 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -1269,7 +1419,7 @@ export type Parser9 =
  * Block to execute in case of error.
  *
  */
-export type Fallback9 =
+export type Fallback10 =
   | boolean
   | number
   | string
@@ -1292,6 +1442,7 @@ export type Fallback9 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1299,23 +1450,23 @@ export type Fallback9 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry9 = number | null
+export type Retry10 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry9 = boolean | string | null
+export type TraceErrorOnRetry10 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role9 = string | null
+export type Role10 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext9 =
+export type PdlContext10 =
   | {
       [k: string]: unknown
     }[]
@@ -1324,10 +1475,10 @@ export type PdlContext9 =
  * Unique identifier for this block
  *
  */
-export type PdlId9 = string | null
-export type PdlIsLeaf9 = false
+export type PdlId10 = string | null
+export type PdlIsLeaf10 = false
 export type IndependentEnum4 = "independent" | "dependent"
-export type Kind9 = "text"
+export type Kind10 = "text"
 /**
  * Body of the text.
  *
@@ -1355,6 +1506,7 @@ export type Text =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | (
@@ -1380,6 +1532,7 @@ export type Text =
       | ReadBlock
       | IncludeBlock
       | ImportBlock
+      | AggregatorBlock
       | ErrorBlock
       | EmptyBlock
       | null
@@ -1389,13 +1542,14 @@ export type Text =
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def10 = string | null
+export type Def11 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute10 = (
+export type Contribute11 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -1403,7 +1557,7 @@ export type Contribute10 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser10 =
+export type Parser11 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -1412,7 +1566,7 @@ export type Parser10 =
  * Block to execute in case of error.
  *
  */
-export type Fallback10 =
+export type Fallback11 =
   | boolean
   | number
   | string
@@ -1435,6 +1589,7 @@ export type Fallback10 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1442,23 +1597,23 @@ export type Fallback10 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry10 = number | null
+export type Retry11 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry10 = boolean | string | null
+export type TraceErrorOnRetry11 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role10 = string | null
+export type Role11 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext10 =
+export type PdlContext11 =
   | {
       [k: string]: unknown
     }[]
@@ -1467,10 +1622,10 @@ export type PdlContext10 =
  * Unique identifier for this block
  *
  */
-export type PdlId10 = string | null
-export type PdlIsLeaf10 = false
+export type PdlId11 = string | null
+export type PdlIsLeaf11 = false
 export type IndependentEnum5 = "independent" | "dependent"
-export type Kind10 = "repeat"
+export type Kind11 = "repeat"
 /**
  * Arrays to iterate over.
  *
@@ -1515,6 +1670,7 @@ export type Repeat =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1582,6 +1738,7 @@ export type PdlTrace2 =
       | ReadBlock
       | IncludeBlock
       | ImportBlock
+      | AggregatorBlock
       | ErrorBlock
       | EmptyBlock
       | null
@@ -1591,13 +1748,14 @@ export type PdlTrace2 =
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def11 = string | null
+export type Def12 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute11 = (
+export type Contribute12 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -1605,7 +1763,7 @@ export type Contribute11 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser11 =
+export type Parser12 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -1614,7 +1772,7 @@ export type Parser11 =
  * Block to execute in case of error.
  *
  */
-export type Fallback11 =
+export type Fallback12 =
   | boolean
   | number
   | string
@@ -1637,6 +1795,7 @@ export type Fallback11 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1644,23 +1803,23 @@ export type Fallback11 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry11 = number | null
+export type Retry12 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry11 = boolean | string | null
+export type TraceErrorOnRetry12 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role11 = string | null
+export type Role12 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext11 =
+export type PdlContext12 =
   | {
       [k: string]: unknown
     }[]
@@ -1669,10 +1828,10 @@ export type PdlContext11 =
  * Unique identifier for this block
  *
  */
-export type PdlId11 = string | null
-export type PdlIsLeaf11 = false
+export type PdlId12 = string | null
+export type PdlIsLeaf12 = false
 export type IndependentEnum6 = "independent" | "dependent"
-export type Kind11 = "match"
+export type Kind12 = "match"
 export type Case =
   | boolean
   | number
@@ -1682,10 +1841,10 @@ export type Case =
   | ObjectPattern
   | AnyPattern
   | null
-export type Def12 = string | null
 export type Def13 = string | null
 export type Def14 = string | null
 export type Def15 = string | null
+export type Def16 = string | null
 export type Any = null
 export type Array1 = (
   | boolean
@@ -1731,6 +1890,7 @@ export type Then =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1746,13 +1906,14 @@ export type With1 = MatchCase[]
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def16 = string | null
+export type Def17 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute12 = (
+export type Contribute13 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -1760,7 +1921,7 @@ export type Contribute12 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser12 =
+export type Parser13 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -1769,7 +1930,7 @@ export type Parser12 =
  * Block to execute in case of error.
  *
  */
-export type Fallback12 =
+export type Fallback13 =
   | boolean
   | number
   | string
@@ -1792,6 +1953,7 @@ export type Fallback12 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1799,23 +1961,23 @@ export type Fallback12 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry12 = number | null
+export type Retry13 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry12 = boolean | string | null
+export type TraceErrorOnRetry13 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role12 = string | null
+export type Role13 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext12 =
+export type PdlContext13 =
   | {
       [k: string]: unknown
     }[]
@@ -1824,10 +1986,10 @@ export type PdlContext12 =
  * Unique identifier for this block
  *
  */
-export type PdlId12 = string | null
-export type PdlIsLeaf12 = false
+export type PdlId13 = string | null
+export type PdlIsLeaf13 = false
 export type IndependentEnum7 = "independent" | "dependent"
-export type Kind12 = "if"
+export type Kind13 = "if"
 /**
  * Condition.
  *
@@ -1860,6 +2022,7 @@ export type Then1 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1890,6 +2053,7 @@ export type Else =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1897,13 +2061,14 @@ export type Else =
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def17 = string | null
+export type Def18 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute13 = (
+export type Contribute14 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -1911,7 +2076,7 @@ export type Contribute13 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser13 =
+export type Parser14 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -1920,7 +2085,7 @@ export type Parser13 =
  * Block to execute in case of error.
  *
  */
-export type Fallback13 =
+export type Fallback14 =
   | boolean
   | number
   | string
@@ -1943,6 +2108,7 @@ export type Fallback13 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -1950,23 +2116,23 @@ export type Fallback13 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry13 = number | null
+export type Retry14 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry13 = boolean | string | null
+export type TraceErrorOnRetry14 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role13 = string | null
+export type Role14 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext13 =
+export type PdlContext14 =
   | {
       [k: string]: unknown
     }[]
@@ -1975,9 +2141,9 @@ export type PdlContext13 =
  * Unique identifier for this block
  *
  */
-export type PdlId13 = string | null
-export type PdlIsLeaf13 = true
-export type Kind13 = "data"
+export type PdlId14 = string | null
+export type PdlIsLeaf14 = true
+export type Kind14 = "data"
 /**
  * Do not evaluate expressions inside strings.
  */
@@ -1986,13 +2152,14 @@ export type Raw = boolean
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def18 = string | null
+export type Def19 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute14 = (
+export type Contribute15 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -2000,7 +2167,7 @@ export type Contribute14 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser14 =
+export type Parser15 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -2009,7 +2176,7 @@ export type Parser14 =
  * Block to execute in case of error.
  *
  */
-export type Fallback14 =
+export type Fallback15 =
   | boolean
   | number
   | string
@@ -2032,6 +2199,7 @@ export type Fallback14 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2039,23 +2207,23 @@ export type Fallback14 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry14 = number | null
+export type Retry15 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry14 = boolean | string | null
+export type TraceErrorOnRetry15 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role14 = string | null
+export type Role15 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext14 =
+export type PdlContext15 =
   | {
       [k: string]: unknown
     }[]
@@ -2064,9 +2232,9 @@ export type PdlContext14 =
  * Unique identifier for this block
  *
  */
-export type PdlId14 = string | null
-export type PdlIsLeaf14 = true
-export type Kind14 = "get"
+export type PdlId15 = string | null
+export type PdlIsLeaf15 = true
+export type Kind15 = "get"
 /**
  * Name of the variable to access.
  */
@@ -2075,13 +2243,14 @@ export type Get = string
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def19 = string | null
+export type Def20 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute15 = (
+export type Contribute16 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -2089,7 +2258,7 @@ export type Contribute15 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser15 =
+export type Parser16 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -2098,7 +2267,7 @@ export type Parser15 =
  * Block to execute in case of error.
  *
  */
-export type Fallback15 =
+export type Fallback16 =
   | boolean
   | number
   | string
@@ -2121,6 +2290,7 @@ export type Fallback15 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2128,23 +2298,23 @@ export type Fallback15 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry15 = number | null
+export type Retry16 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry15 = boolean | string | null
+export type TraceErrorOnRetry16 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role15 = string | null
+export type Role16 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext15 =
+export type PdlContext16 =
   | {
       [k: string]: unknown
     }[]
@@ -2153,9 +2323,9 @@ export type PdlContext15 =
  * Unique identifier for this block
  *
  */
-export type PdlId15 = string | null
-export type PdlIsLeaf15 = true
-export type Kind15 = "code"
+export type PdlId16 = string | null
+export type PdlIsLeaf16 = true
+export type Kind16 = "code"
 export type Lang = "command"
 /**
  * The argument vector to spawn.
@@ -2166,13 +2336,14 @@ export type Args = (LocalizedExpression | string)[]
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def20 = string | null
+export type Def21 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute16 = (
+export type Contribute17 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -2180,7 +2351,7 @@ export type Contribute16 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser16 =
+export type Parser17 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -2189,7 +2360,7 @@ export type Parser16 =
  * Block to execute in case of error.
  *
  */
-export type Fallback16 =
+export type Fallback17 =
   | boolean
   | number
   | string
@@ -2212,6 +2383,7 @@ export type Fallback16 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2219,23 +2391,23 @@ export type Fallback16 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry16 = number | null
+export type Retry17 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry16 = boolean | string | null
+export type TraceErrorOnRetry17 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role16 = string | null
+export type Role17 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext16 =
+export type PdlContext17 =
   | {
       [k: string]: unknown
     }[]
@@ -2244,9 +2416,9 @@ export type PdlContext16 =
  * Unique identifier for this block
  *
  */
-export type PdlId16 = string | null
-export type PdlIsLeaf16 = true
-export type Kind16 = "code"
+export type PdlId17 = string | null
+export type PdlIsLeaf17 = true
+export type Kind17 = "code"
 /**
  * Programming language of the code.
  *
@@ -2279,6 +2451,7 @@ export type Code =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2286,13 +2459,14 @@ export type Code =
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def21 = string | null
+export type Def22 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute17 = (
+export type Contribute18 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -2300,7 +2474,7 @@ export type Contribute17 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser17 =
+export type Parser18 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -2309,7 +2483,7 @@ export type Parser17 =
  * Block to execute in case of error.
  *
  */
-export type Fallback17 =
+export type Fallback18 =
   | boolean
   | number
   | string
@@ -2332,6 +2506,7 @@ export type Fallback17 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2339,23 +2514,23 @@ export type Fallback17 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry17 = number | null
+export type Retry18 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry17 = boolean | string | null
+export type TraceErrorOnRetry18 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role17 = string | null
+export type Role18 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext17 =
+export type PdlContext18 =
   | {
       [k: string]: unknown
     }[]
@@ -2364,9 +2539,9 @@ export type PdlContext17 =
  * Unique identifier for this block
  *
  */
-export type PdlId17 = string | null
-export type PdlIsLeaf17 = true
-export type Kind17 = "model"
+export type PdlId18 = string | null
+export type PdlIsLeaf18 = true
+export type Kind18 = "model"
 /**
  * Messages to send to the model.
  *
@@ -2394,6 +2569,7 @@ export type Input =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2429,13 +2605,14 @@ export type Parameters =
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def22 = string | null
+export type Def23 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute18 = (
+export type Contribute19 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -2443,7 +2620,7 @@ export type Contribute18 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser18 =
+export type Parser19 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -2452,7 +2629,7 @@ export type Parser18 =
  * Block to execute in case of error.
  *
  */
-export type Fallback18 =
+export type Fallback19 =
   | boolean
   | number
   | string
@@ -2475,6 +2652,7 @@ export type Fallback18 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2482,23 +2660,23 @@ export type Fallback18 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry18 = number | null
+export type Retry19 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry18 = boolean | string | null
+export type TraceErrorOnRetry19 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role18 = string | null
+export type Role19 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext18 =
+export type PdlContext19 =
   | {
       [k: string]: unknown
     }[]
@@ -2507,9 +2685,9 @@ export type PdlContext18 =
  * Unique identifier for this block
  *
  */
-export type PdlId18 = string | null
-export type PdlIsLeaf18 = true
-export type Kind18 = "model"
+export type PdlId19 = string | null
+export type PdlIsLeaf19 = true
+export type Kind19 = "model"
 /**
  * Messages to send to the model.
  *
@@ -2537,6 +2715,7 @@ export type Input1 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2623,13 +2802,14 @@ export type MaxRetries = number | string | null
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def23 = string | null
+export type Def24 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute19 = (
+export type Contribute20 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -2637,7 +2817,7 @@ export type Contribute19 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser19 =
+export type Parser20 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -2646,7 +2826,7 @@ export type Parser19 =
  * Block to execute in case of error.
  *
  */
-export type Fallback19 =
+export type Fallback20 =
   | boolean
   | number
   | string
@@ -2669,6 +2849,7 @@ export type Fallback19 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2676,23 +2857,23 @@ export type Fallback19 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry19 = number | null
+export type Retry20 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry19 = boolean | string | null
+export type TraceErrorOnRetry20 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role19 = string | null
+export type Role20 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext19 =
+export type PdlContext20 =
   | {
       [k: string]: unknown
     }[]
@@ -2701,9 +2882,9 @@ export type PdlContext19 =
  * Unique identifier for this block
  *
  */
-export type PdlId19 = string | null
-export type PdlIsLeaf19 = true
-export type Kind19 = "call"
+export type PdlId20 = string | null
+export type PdlIsLeaf20 = true
+export type Kind20 = "call"
 /**
  * Function to call.
  *
@@ -2732,6 +2913,7 @@ export type PdlTrace3 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2739,13 +2921,14 @@ export type PdlTrace3 =
  * Name of the variable used to store the result of the execution of the block.
  *
  */
-export type Def24 = string | null
+export type Def25 = string | null
 /**
  * Indicate if the block contributes to the result and background context.
  *
  */
-export type Contribute20 = (
+export type Contribute21 = (
   | ContributeTarget
+  | string
   | {
       [k: string]: ContributeValue
     }
@@ -2753,7 +2936,7 @@ export type Contribute20 = (
 /**
  * Parser to use to construct a value out of a string result.
  */
-export type Parser20 =
+export type Parser21 =
   | ("json" | "jsonl" | "yaml")
   | PdlParser
   | RegexParser
@@ -2762,7 +2945,7 @@ export type Parser20 =
  * Block to execute in case of error.
  *
  */
-export type Fallback20 =
+export type Fallback21 =
   | boolean
   | number
   | string
@@ -2785,6 +2968,7 @@ export type Fallback20 =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2792,23 +2976,23 @@ export type Fallback20 =
  * The maximum number of times to retry when an error occurs within a block.
  *
  */
-export type Retry20 = number | null
+export type Retry21 = number | null
 /**
  * Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.
  *
  */
-export type TraceErrorOnRetry20 = boolean | string | null
+export type TraceErrorOnRetry21 = boolean | string | null
 /**
  * Role associated to the block and sub-blocks.
  * Typical roles are `system`, `user`, and `assistant`,
  * but there may be other roles such as `available_tools`.
  */
-export type Role20 = string | null
+export type Role21 = string | null
 /**
  * Current context
  *
  */
-export type PdlContext20 =
+export type PdlContext21 =
   | {
       [k: string]: unknown
     }[]
@@ -2817,9 +3001,9 @@ export type PdlContext20 =
  * Unique identifier for this block
  *
  */
-export type PdlId20 = string | null
-export type PdlIsLeaf20 = true
-export type Kind20 = "function"
+export type PdlId21 = string | null
+export type PdlIsLeaf21 = true
+export type Kind21 = "function"
 /**
  * Functions parameters with their types.
  *
@@ -2854,6 +3038,7 @@ export type Return =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2885,6 +3070,7 @@ export type PdlBlock =
   | ReadBlock
   | IncludeBlock
   | ImportBlock
+  | AggregatorBlock
   | ErrorBlock
   | EmptyBlock
   | null
@@ -2924,20 +3110,20 @@ export interface FunctionBlock {
       }
     | null
   defs?: Defs
-  def?: Def24
-  contribute?: Contribute20
-  parser?: Parser20
-  fallback?: Fallback20
-  retry?: Retry20
-  trace_error_on_retry?: TraceErrorOnRetry20
-  role?: Role20
-  pdl__context?: PdlContext20
-  pdl__id?: PdlId20
+  def?: Def25
+  contribute?: Contribute21
+  parser?: Parser21
+  fallback?: Fallback21
+  retry?: Retry21
+  trace_error_on_retry?: TraceErrorOnRetry21
+  role?: Role21
+  pdl__context?: PdlContext21
+  pdl__id?: PdlId21
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf20
-  kind?: Kind20
+  pdl__is_leaf?: PdlIsLeaf21
+  kind?: Kind21
   function: Function
   return: Return
   signature?: Signature
@@ -2999,6 +3185,7 @@ export interface Defs {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3038,20 +3225,20 @@ export interface CallBlock {
       }
     | null
   defs?: Defs1
-  def?: Def23
-  contribute?: Contribute19
-  parser?: Parser19
-  fallback?: Fallback19
-  retry?: Retry19
-  trace_error_on_retry?: TraceErrorOnRetry19
-  role?: Role19
-  pdl__context?: PdlContext19
-  pdl__id?: PdlId19
+  def?: Def24
+  contribute?: Contribute20
+  parser?: Parser20
+  fallback?: Fallback20
+  retry?: Retry20
+  trace_error_on_retry?: TraceErrorOnRetry20
+  role?: Role20
+  pdl__context?: PdlContext20
+  pdl__id?: PdlId20
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf19
-  kind?: Kind19
+  pdl__is_leaf?: PdlIsLeaf20
+  kind?: Kind20
   call: Call
   args?: unknown
   pdl__trace?: PdlTrace3
@@ -3084,6 +3271,7 @@ export interface Defs1 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3130,20 +3318,20 @@ export interface LitellmModelBlock {
       }
     | null
   defs?: Defs2
-  def?: Def22
-  contribute?: Contribute18
-  parser?: Parser18
-  fallback?: Fallback18
-  retry?: Retry18
-  trace_error_on_retry?: TraceErrorOnRetry18
-  role?: Role18
-  pdl__context?: PdlContext18
-  pdl__id?: PdlId18
+  def?: Def23
+  contribute?: Contribute19
+  parser?: Parser19
+  fallback?: Fallback19
+  retry?: Retry19
+  trace_error_on_retry?: TraceErrorOnRetry19
+  role?: Role19
+  pdl__context?: PdlContext19
+  pdl__id?: PdlId19
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf18
-  kind?: Kind18
+  pdl__is_leaf?: PdlIsLeaf19
+  kind?: Kind19
   input?: Input1
   modelResponse?: Modelresponse1
   /**
@@ -3184,6 +3372,7 @@ export interface Defs2 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3223,20 +3412,20 @@ export interface GraniteioModelBlock {
       }
     | null
   defs?: Defs3
-  def?: Def21
-  contribute?: Contribute17
-  parser?: Parser17
-  fallback?: Fallback17
-  retry?: Retry17
-  trace_error_on_retry?: TraceErrorOnRetry17
-  role?: Role17
-  pdl__context?: PdlContext17
-  pdl__id?: PdlId17
+  def?: Def22
+  contribute?: Contribute18
+  parser?: Parser18
+  fallback?: Fallback18
+  retry?: Retry18
+  trace_error_on_retry?: TraceErrorOnRetry18
+  role?: Role18
+  pdl__context?: PdlContext18
+  pdl__id?: PdlId18
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf17
-  kind?: Kind17
+  pdl__is_leaf?: PdlIsLeaf18
+  kind?: Kind18
   input?: Input
   modelResponse?: Modelresponse
   /**
@@ -3277,6 +3466,7 @@ export interface Defs3 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3325,20 +3515,20 @@ export interface CodeBlock {
       }
     | null
   defs?: Defs4
-  def?: Def20
-  contribute?: Contribute16
-  parser?: Parser16
-  fallback?: Fallback16
-  retry?: Retry16
-  trace_error_on_retry?: TraceErrorOnRetry16
-  role?: Role16
-  pdl__context?: PdlContext16
-  pdl__id?: PdlId16
+  def?: Def21
+  contribute?: Contribute17
+  parser?: Parser17
+  fallback?: Fallback17
+  retry?: Retry17
+  trace_error_on_retry?: TraceErrorOnRetry17
+  role?: Role17
+  pdl__context?: PdlContext17
+  pdl__id?: PdlId17
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf16
-  kind?: Kind16
+  pdl__is_leaf?: PdlIsLeaf17
+  kind?: Kind17
   lang: Lang1
   code: Code
 }
@@ -3370,6 +3560,7 @@ export interface Defs4 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3417,20 +3608,20 @@ export interface ArgsBlock {
       }
     | null
   defs?: Defs5
-  def?: Def19
-  contribute?: Contribute15
-  parser?: Parser15
-  fallback?: Fallback15
-  retry?: Retry15
-  trace_error_on_retry?: TraceErrorOnRetry15
-  role?: Role15
-  pdl__context?: PdlContext15
-  pdl__id?: PdlId15
+  def?: Def20
+  contribute?: Contribute16
+  parser?: Parser16
+  fallback?: Fallback16
+  retry?: Retry16
+  trace_error_on_retry?: TraceErrorOnRetry16
+  role?: Role16
+  pdl__context?: PdlContext16
+  pdl__id?: PdlId16
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf15
-  kind?: Kind15
+  pdl__is_leaf?: PdlIsLeaf16
+  kind?: Kind16
   lang?: Lang
   args: Args
 }
@@ -3462,6 +3653,7 @@ export interface Defs5 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3503,20 +3695,20 @@ export interface GetBlock {
       }
     | null
   defs?: Defs6
-  def?: Def18
-  contribute?: Contribute14
-  parser?: Parser14
-  fallback?: Fallback14
-  retry?: Retry14
-  trace_error_on_retry?: TraceErrorOnRetry14
-  role?: Role14
-  pdl__context?: PdlContext14
-  pdl__id?: PdlId14
+  def?: Def19
+  contribute?: Contribute15
+  parser?: Parser15
+  fallback?: Fallback15
+  retry?: Retry15
+  trace_error_on_retry?: TraceErrorOnRetry15
+  role?: Role15
+  pdl__context?: PdlContext15
+  pdl__id?: PdlId15
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf14
-  kind?: Kind14
+  pdl__is_leaf?: PdlIsLeaf15
+  kind?: Kind15
   get: Get
 }
 /**
@@ -3547,6 +3739,7 @@ export interface Defs6 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3607,20 +3800,20 @@ export interface DataBlock {
       }
     | null
   defs?: Defs7
-  def?: Def17
-  contribute?: Contribute13
-  parser?: Parser13
-  fallback?: Fallback13
-  retry?: Retry13
-  trace_error_on_retry?: TraceErrorOnRetry13
-  role?: Role13
-  pdl__context?: PdlContext13
-  pdl__id?: PdlId13
+  def?: Def18
+  contribute?: Contribute14
+  parser?: Parser14
+  fallback?: Fallback14
+  retry?: Retry14
+  trace_error_on_retry?: TraceErrorOnRetry14
+  role?: Role14
+  pdl__context?: PdlContext14
+  pdl__id?: PdlId14
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf13
-  kind?: Kind13
+  pdl__is_leaf?: PdlIsLeaf14
+  kind?: Kind14
   data: unknown
   raw?: Raw
 }
@@ -3652,6 +3845,7 @@ export interface Defs7 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3701,21 +3895,21 @@ export interface IfBlock {
       }
     | null
   defs?: Defs8
-  def?: Def16
-  contribute?: Contribute12
-  parser?: Parser12
-  fallback?: Fallback12
-  retry?: Retry12
-  trace_error_on_retry?: TraceErrorOnRetry12
-  role?: Role12
-  pdl__context?: PdlContext12
-  pdl__id?: PdlId12
+  def?: Def17
+  contribute?: Contribute13
+  parser?: Parser13
+  fallback?: Fallback13
+  retry?: Retry13
+  trace_error_on_retry?: TraceErrorOnRetry13
+  role?: Role13
+  pdl__context?: PdlContext13
+  pdl__id?: PdlId13
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf12
+  pdl__is_leaf?: PdlIsLeaf13
   context?: IndependentEnum7
-  kind?: Kind12
+  kind?: Kind13
   if: If1
   then: Then1
   else?: Else
@@ -3748,6 +3942,7 @@ export interface Defs8 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3804,21 +3999,21 @@ export interface MatchBlock {
       }
     | null
   defs?: Defs9
-  def?: Def11
-  contribute?: Contribute11
-  parser?: Parser11
-  fallback?: Fallback11
-  retry?: Retry11
-  trace_error_on_retry?: TraceErrorOnRetry11
-  role?: Role11
-  pdl__context?: PdlContext11
-  pdl__id?: PdlId11
+  def?: Def12
+  contribute?: Contribute12
+  parser?: Parser12
+  fallback?: Fallback12
+  retry?: Retry12
+  trace_error_on_retry?: TraceErrorOnRetry12
+  role?: Role12
+  pdl__context?: PdlContext12
+  pdl__id?: PdlId12
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf11
+  pdl__is_leaf?: PdlIsLeaf12
   context?: IndependentEnum6
-  kind?: Kind11
+  kind?: Kind12
   match: unknown
   with: With1
 }
@@ -3850,6 +4045,7 @@ export interface Defs9 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3908,21 +4104,21 @@ export interface RepeatBlock {
       }
     | null
   defs?: Defs10
-  def?: Def10
-  contribute?: Contribute10
-  parser?: Parser10
-  fallback?: Fallback10
-  retry?: Retry10
-  trace_error_on_retry?: TraceErrorOnRetry10
-  role?: Role10
-  pdl__context?: PdlContext10
-  pdl__id?: PdlId10
+  def?: Def11
+  contribute?: Contribute11
+  parser?: Parser11
+  fallback?: Fallback11
+  retry?: Retry11
+  trace_error_on_retry?: TraceErrorOnRetry11
+  role?: Role11
+  pdl__context?: PdlContext11
+  pdl__id?: PdlId11
   pdl__result?: unknown
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
-  pdl__is_leaf?: PdlIsLeaf10
+  pdl__is_leaf?: PdlIsLeaf11
   context?: IndependentEnum5
-  kind?: Kind10
+  kind?: Kind11
   for?: For
   index?: Index
   while?: While
@@ -3960,6 +4156,7 @@ export interface Defs10 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -3999,6 +4196,91 @@ export interface TextBlock {
       }
     | null
   defs?: Defs11
+  def?: Def10
+  contribute?: Contribute10
+  parser?: Parser10
+  fallback?: Fallback10
+  retry?: Retry10
+  trace_error_on_retry?: TraceErrorOnRetry10
+  role?: Role10
+  pdl__context?: PdlContext10
+  pdl__id?: PdlId10
+  pdl__result?: unknown
+  pdl__location?: PdlLocationType | null
+  pdl__timing?: PdlTiming | null
+  pdl__is_leaf?: PdlIsLeaf10
+  context?: IndependentEnum4
+  kind?: Kind10
+  text: Text
+}
+/**
+ * Set of definitions executed before the execution of the block.
+ *
+ */
+export interface Defs11 {
+  [k: string]:
+    | boolean
+    | number
+    | string
+    | FunctionBlock
+    | CallBlock
+    | LitellmModelBlock
+    | GraniteioModelBlock
+    | CodeBlock
+    | ArgsBlock
+    | GetBlock
+    | DataBlock
+    | IfBlock
+    | MatchBlock
+    | RepeatBlock
+    | TextBlock
+    | LastOfBlock
+    | ArrayBlock
+    | ObjectBlock
+    | MessageBlock
+    | ReadBlock
+    | IncludeBlock
+    | ImportBlock
+    | AggregatorBlock
+    | ErrorBlock
+    | EmptyBlock
+    | null
+}
+/**
+ * Return the value of the last block if the list of blocks.
+ */
+export interface LastOfBlock {
+  description?: Description12
+  /**
+   * Type specification of the result of the block.
+   *
+   */
+  spec?:
+    | (
+        | "null"
+        | "boolean"
+        | "string"
+        | "number"
+        | "integer"
+        | "array"
+        | "object"
+        | "bool"
+        | "str"
+        | "float"
+        | "int"
+        | "list"
+        | "obj"
+      )
+    | EnumPdlType
+    | PdlTypeType[]
+    | OptionalPdlType
+    | JsonSchemaTypePdlType
+    | ObjectPdlType
+    | {
+        [k: string]: PdlTypeType
+      }
+    | null
+  defs?: Defs12
   def?: Def9
   contribute?: Contribute9
   parser?: Parser9
@@ -4012,15 +4294,15 @@ export interface TextBlock {
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
   pdl__is_leaf?: PdlIsLeaf9
-  context?: IndependentEnum4
+  context?: IndependentEnum3
   kind?: Kind9
-  text: Text
+  lastOf: Lastof
 }
 /**
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs11 {
+export interface Defs12 {
   [k: string]:
     | boolean
     | number
@@ -4044,15 +4326,16 @@ export interface Defs11 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
 }
 /**
- * Return the value of the last block if the list of blocks.
+ * Return the array of values computed by each block of the list of blocks.
  */
-export interface LastOfBlock {
-  description?: Description12
+export interface ArrayBlock {
+  description?: Description13
   /**
    * Type specification of the result of the block.
    *
@@ -4082,7 +4365,7 @@ export interface LastOfBlock {
         [k: string]: PdlTypeType
       }
     | null
-  defs?: Defs12
+  defs?: Defs13
   def?: Def8
   contribute?: Contribute8
   parser?: Parser8
@@ -4096,15 +4379,15 @@ export interface LastOfBlock {
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
   pdl__is_leaf?: PdlIsLeaf8
-  context?: IndependentEnum3
+  context?: IndependentEnum2
   kind?: Kind8
-  lastOf: Lastof
+  array: Array
 }
 /**
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs12 {
+export interface Defs13 {
   [k: string]:
     | boolean
     | number
@@ -4128,15 +4411,16 @@ export interface Defs12 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
 }
 /**
- * Return the array of values computed by each block of the list of blocks.
+ * Return the object where the value of each field is defined by a block. If the body of the object is an array, the resulting object is the union of the objects computed by each element of the array.
  */
-export interface ArrayBlock {
-  description?: Description13
+export interface ObjectBlock {
+  description?: Description14
   /**
    * Type specification of the result of the block.
    *
@@ -4166,7 +4450,7 @@ export interface ArrayBlock {
         [k: string]: PdlTypeType
       }
     | null
-  defs?: Defs13
+  defs?: Defs14
   def?: Def7
   contribute?: Contribute7
   parser?: Parser7
@@ -4180,15 +4464,15 @@ export interface ArrayBlock {
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
   pdl__is_leaf?: PdlIsLeaf7
-  context?: IndependentEnum2
+  context?: IndependentEnum1
   kind?: Kind7
-  array: Array
+  object: Object1
 }
 /**
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs13 {
+export interface Defs14 {
   [k: string]:
     | boolean
     | number
@@ -4212,15 +4496,16 @@ export interface Defs13 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
 }
 /**
- * Return the object where the value of each field is defined by a block. If the body of the object is an array, the resulting object is the union of the objects computed by each element of the array.
+ * Create a message.
  */
-export interface ObjectBlock {
-  description?: Description14
+export interface MessageBlock {
+  description?: Description15
   /**
    * Type specification of the result of the block.
    *
@@ -4250,7 +4535,7 @@ export interface ObjectBlock {
         [k: string]: PdlTypeType
       }
     | null
-  defs?: Defs14
+  defs?: Defs15
   def?: Def6
   contribute?: Contribute6
   parser?: Parser6
@@ -4264,15 +4549,16 @@ export interface ObjectBlock {
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
   pdl__is_leaf?: PdlIsLeaf6
-  context?: IndependentEnum1
   kind?: Kind6
-  object: Object1
+  content: Content
+  name?: Name
+  tool_call_id?: ToolCallId
 }
 /**
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs14 {
+export interface Defs15 {
   [k: string]:
     | boolean
     | number
@@ -4296,15 +4582,28 @@ export interface Defs14 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
 }
 /**
- * Create a message.
+ * Read from a file or standard input.
+ *
+ * Example. Read from the standard input with a prompt starting with `> `.
+ * ```PDL
+ * read:
+ * message: "> "
+ * ```
+ *
+ * Example. Read the file `./data.yaml` in the same directory of the PDL file containing the block and parse it into YAML.
+ * ```PDL
+ * read: ./data.yaml
+ * parser: yaml
+ * ```
  */
-export interface MessageBlock {
-  description?: Description15
+export interface ReadBlock {
+  description?: Description16
   /**
    * Type specification of the result of the block.
    *
@@ -4334,7 +4633,7 @@ export interface MessageBlock {
         [k: string]: PdlTypeType
       }
     | null
-  defs?: Defs15
+  defs?: Defs16
   def?: Def5
   contribute?: Contribute5
   parser?: Parser5
@@ -4349,15 +4648,15 @@ export interface MessageBlock {
   pdl__timing?: PdlTiming | null
   pdl__is_leaf?: PdlIsLeaf5
   kind?: Kind5
-  content: Content
-  name?: Name
-  tool_call_id?: ToolCallId
+  read: Read
+  message?: Message
+  multiline?: Multiline
 }
 /**
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs15 {
+export interface Defs16 {
   [k: string]:
     | boolean
     | number
@@ -4381,27 +4680,16 @@ export interface Defs15 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
 }
 /**
- * Read from a file or standard input.
- *
- * Example. Read from the standard input with a prompt starting with `> `.
- * ```PDL
- * read:
- * message: "> "
- * ```
- *
- * Example. Read the file `./data.yaml` in the same directory of the PDL file containing the block and parse it into YAML.
- * ```PDL
- * read: ./data.yaml
- * parser: yaml
- * ```
+ * Include a PDL file.
  */
-export interface ReadBlock {
-  description?: Description16
+export interface IncludeBlock {
+  description?: Description17
   /**
    * Type specification of the result of the block.
    *
@@ -4431,7 +4719,7 @@ export interface ReadBlock {
         [k: string]: PdlTypeType
       }
     | null
-  defs?: Defs16
+  defs?: Defs17
   def?: Def4
   contribute?: Contribute4
   parser?: Parser4
@@ -4445,16 +4733,16 @@ export interface ReadBlock {
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
   pdl__is_leaf?: PdlIsLeaf4
+  context?: IndependentEnum
   kind?: Kind4
-  read: Read
-  message?: Message
-  multiline?: Multiline
+  include: Include
+  pdl__trace?: PdlTrace1
 }
 /**
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs16 {
+export interface Defs17 {
   [k: string]:
     | boolean
     | number
@@ -4478,15 +4766,16 @@ export interface Defs16 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
 }
 /**
- * Include a PDL file.
+ * Import a PDL file.
  */
-export interface IncludeBlock {
-  description?: Description17
+export interface ImportBlock {
+  description?: Description18
   /**
    * Type specification of the result of the block.
    *
@@ -4516,7 +4805,7 @@ export interface IncludeBlock {
         [k: string]: PdlTypeType
       }
     | null
-  defs?: Defs17
+  defs?: Defs18
   def?: Def3
   contribute?: Contribute3
   parser?: Parser3
@@ -4530,16 +4819,15 @@ export interface IncludeBlock {
   pdl__location?: PdlLocationType | null
   pdl__timing?: PdlTiming | null
   pdl__is_leaf?: PdlIsLeaf3
-  context?: IndependentEnum
   kind?: Kind3
-  include: Include
-  pdl__trace?: PdlTrace1
+  import: Import
+  pdl__trace?: PdlTrace
 }
 /**
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs17 {
+export interface Defs18 {
   [k: string]:
     | boolean
     | number
@@ -4563,15 +4851,16 @@ export interface Defs17 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
 }
 /**
- * Import a PDL file.
+ * Create a new aggregator that can be use in the `contribute` field.
  */
-export interface ImportBlock {
-  description?: Description18
+export interface AggregatorBlock {
+  description?: Description19
   /**
    * Type specification of the result of the block.
    *
@@ -4601,7 +4890,7 @@ export interface ImportBlock {
         [k: string]: PdlTypeType
       }
     | null
-  defs?: Defs18
+  defs?: Defs19
   def?: Def2
   contribute?: Contribute2
   parser?: Parser2
@@ -4616,14 +4905,13 @@ export interface ImportBlock {
   pdl__timing?: PdlTiming | null
   pdl__is_leaf?: PdlIsLeaf2
   kind?: Kind2
-  import: Import
-  pdl__trace?: PdlTrace
+  aggregator: Aggregator
 }
 /**
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs18 {
+export interface Defs19 {
   [k: string]:
     | boolean
     | number
@@ -4647,6 +4935,7 @@ export interface Defs18 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -4655,7 +4944,7 @@ export interface Defs18 {
  * Block representing an error generated at runtime.
  */
 export interface ErrorBlock {
-  description?: Description19
+  description?: Description20
   /**
    * Type specification of the result of the block.
    *
@@ -4685,7 +4974,7 @@ export interface ErrorBlock {
         [k: string]: PdlTypeType
       }
     | null
-  defs?: Defs19
+  defs?: Defs20
   def?: Def1
   contribute?: Contribute1
   parser?: Parser1
@@ -4707,7 +4996,7 @@ export interface ErrorBlock {
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs19 {
+export interface Defs20 {
   [k: string]:
     | boolean
     | number
@@ -4731,6 +5020,7 @@ export interface Defs19 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -4739,7 +5029,7 @@ export interface Defs19 {
  * Block without an action. It can contain definitions.
  */
 export interface EmptyBlock {
-  description?: Description20
+  description?: Description21
   /**
    * Type specification of the result of the block.
    *
@@ -4769,7 +5059,7 @@ export interface EmptyBlock {
         [k: string]: PdlTypeType
       }
     | null
-  defs?: Defs20
+  defs?: Defs21
   def?: Def
   contribute?: Contribute
   parser?: Parser
@@ -4789,7 +5079,7 @@ export interface EmptyBlock {
  * Set of definitions executed before the execution of the block.
  *
  */
-export interface Defs20 {
+export interface Defs21 {
   [k: string]:
     | boolean
     | number
@@ -4813,6 +5103,7 @@ export interface Defs20 {
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
     | null
@@ -4821,32 +5112,13 @@ export interface Defs20 {
  * Contribution of a specific value instead of the default one.
  */
 export interface ContributeValue {
-  value: Value
-}
-export interface LocalizedExpression {
-  pdl__expr: PdlExpr
-  pdl__result?: unknown
-  pdl__location?: PdlLocationType | null
-}
-export interface PdlExpr {
-  [k: string]: unknown
-}
-/**
- * Internal data structure to keep track of the source location information.
- */
-export interface PdlLocationType {
-  path: Path
-  file: File
-  table: Table
-}
-export interface Table {
-  [k: string]: number
+  value: unknown
 }
 /**
  * Use a PDL program as a parser specification (experimental).
  */
 export interface PdlParser {
-  description?: Description21
+  description?: Description22
   spec?:
     | (
         | "null"
@@ -4878,7 +5150,7 @@ export interface PdlParser {
  * A regular expression parser.
  */
 export interface RegexParser {
-  description?: Description22
+  description?: Description23
   spec?:
     | (
         | "null"
@@ -4907,6 +5179,17 @@ export interface RegexParser {
   regex: Regex
   mode?: Mode
 }
+/**
+ * Internal data structure to keep track of the source location information.
+ */
+export interface PdlLocationType {
+  path: Path
+  file: File
+  table: Table
+}
+export interface Table {
+  [k: string]: number
+}
 /**
  * Internal data structure to record timing information in the trace.
  */
@@ -4916,6 +5199,23 @@ export interface PdlTiming {
   first_use_nanos?: FirstUseNanos
   timezone?: Timezone
 }
+export interface FileAggregatorConfig {
+  description?: Description24
+  file: File1
+  mode?: Mode1
+  encoding?: Encoding
+  prefix?: Prefix
+  suffix?: Suffix
+  flush?: Flush
+}
+export interface LocalizedExpression {
+  pdl__expr: PdlExpr
+  pdl__result?: unknown
+  pdl__location?: PdlLocationType | null
+}
+export interface PdlExpr {
+  [k: string]: unknown
+}
 /**
  * Join loop iterations as a string.
  */
@@ -4956,21 +5256,21 @@ export interface MatchCase {
  * Match any of the patterns.
  */
 export interface OrPattern {
-  def?: Def12
+  def?: Def13
   anyOf: Anyof
 }
 /**
  * Match an array.
  */
 export interface ArrayPattern {
-  def?: Def13
+  def?: Def14
   array: Array1
 }
 /**
  * Match an object.
  */
 export interface ObjectPattern {
-  def?: Def14
+  def?: Def15
   object: Object2
 }
 export interface Object2 {
@@ -4988,7 +5288,7 @@ export interface Object2 {
  * Match any value.
  */
 export interface AnyPattern {
-  def?: Def15
+  def?: Def16
   any: Any
 }
 /**
diff --git a/pdl-live-react/src/pdl_ast_utils.ts b/pdl-live-react/src/pdl_ast_utils.ts
index 7d57cd947..a0741a7ac 100644
--- a/pdl-live-react/src/pdl_ast_utils.ts
+++ b/pdl-live-react/src/pdl_ast_utils.ts
@@ -47,7 +47,7 @@ export function map_block_children(
   }
   // @ts-expect-error: TODO
   new_block = match(new_block)
-    // .with(P.string, s => s)
+    .with(P.union(P.nullish, P.boolean, P.number, P.string), (v) => v)
     .with({ kind: "empty" }, (block) => block)
     .with({ kind: "function" }, (block) => {
       const return_ = f_block(block.return)
@@ -202,6 +202,7 @@ export function map_block_children(
     })
     .with({ kind: "include" }, (block) => block)
     .with({ kind: "import" }, (block) => block)
+    .with({ kind: "aggregator" }, (block) => block)
     .with({ kind: undefined }, (block) => block)
     .exhaustive()
   match(new_block)
@@ -293,6 +294,7 @@ export function iter_block_children(
     .with({ kind: "read" }, () => {})
     .with({ kind: "include" }, () => {})
     .with({ kind: "import" }, () => {})
+    .with({ kind: "aggregator" }, () => {})
     .with({ kind: undefined }, () => {})
     .exhaustive()
   match(block)
diff --git a/pdl-live-react/src/view/timeline/model.ts b/pdl-live-react/src/view/timeline/model.ts
index c384c3e70..043e77c52 100644
--- a/pdl-live-react/src/view/timeline/model.ts
+++ b/pdl-live-react/src/view/timeline/model.ts
@@ -135,6 +135,7 @@ export function childrenOf(block: NonScalarPdlBlock) {
     .with({ kind: "read" }, (data) => [data.pdl__result])
     .with({ kind: "include" }, (data) => [data.pdl__trace ?? data.pdl__result])
     .with({ kind: "import" }, (data) => [data.pdl__trace ?? data.pdl__result])
+    .with({ kind: "aggregator" }, () => [])
     .with({ kind: "function" }, () => [])
     .with({ kind: "call" }, (data) => [data.pdl__trace ?? data.pdl__result])
     .with({ kind: "text" }, (data) => [data.text])
diff --git a/src/pdl/pdl-schema.json b/src/pdl/pdl-schema.json
index 17a6c3f60..a83ceafc7 100644
--- a/src/pdl/pdl-schema.json
+++ b/src/pdl/pdl-schema.json
@@ -1,5 +1,404 @@
 {
   "$defs": {
+    "AggregatorBlock": {
+      "additionalProperties": false,
+      "description": "Create a new aggregator that can be use in the `contribute` field.",
+      "properties": {
+        "description": {
+          "anyOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Documentation associated to the block.\n    ",
+          "title": "Description"
+        },
+        "spec": {
+          "$ref": "#/$defs/PdlTypeType",
+          "default": null,
+          "description": "Type specification of the result of the block.\n    "
+        },
+        "defs": {
+          "additionalProperties": {
+            "anyOf": [
+              {
+                "type": "boolean"
+              },
+              {
+                "type": "integer"
+              },
+              {
+                "type": "number"
+              },
+              {
+                "type": "string"
+              },
+              {
+                "$ref": "#/$defs/FunctionBlock"
+              },
+              {
+                "$ref": "#/$defs/CallBlock"
+              },
+              {
+                "$ref": "#/$defs/LitellmModelBlock"
+              },
+              {
+                "$ref": "#/$defs/GraniteioModelBlock"
+              },
+              {
+                "$ref": "#/$defs/CodeBlock"
+              },
+              {
+                "$ref": "#/$defs/ArgsBlock"
+              },
+              {
+                "$ref": "#/$defs/GetBlock"
+              },
+              {
+                "$ref": "#/$defs/DataBlock"
+              },
+              {
+                "$ref": "#/$defs/IfBlock"
+              },
+              {
+                "$ref": "#/$defs/MatchBlock"
+              },
+              {
+                "$ref": "#/$defs/RepeatBlock"
+              },
+              {
+                "$ref": "#/$defs/TextBlock"
+              },
+              {
+                "$ref": "#/$defs/LastOfBlock"
+              },
+              {
+                "$ref": "#/$defs/ArrayBlock"
+              },
+              {
+                "$ref": "#/$defs/ObjectBlock"
+              },
+              {
+                "$ref": "#/$defs/MessageBlock"
+              },
+              {
+                "$ref": "#/$defs/ReadBlock"
+              },
+              {
+                "$ref": "#/$defs/IncludeBlock"
+              },
+              {
+                "$ref": "#/$defs/ImportBlock"
+              },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
+              {
+                "$ref": "#/$defs/ErrorBlock"
+              },
+              {
+                "$ref": "#/$defs/EmptyBlock"
+              },
+              {
+                "type": "null"
+              }
+            ]
+          },
+          "default": {},
+          "description": "Set of definitions executed before the execution of the block.\n    ",
+          "title": "Defs",
+          "type": "object"
+        },
+        "def": {
+          "anyOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Name of the variable used to store the result of the execution of the block.\n    ",
+          "title": "Def"
+        },
+        "contribute": {
+          "default": [
+            "result",
+            "context"
+          ],
+          "description": "Indicate if the block contributes to the result and background context.\n    ",
+          "items": {
+            "anyOf": [
+              {
+                "$ref": "#/$defs/ContributeTarget"
+              },
+              {
+                "type": "string"
+              },
+              {
+                "additionalProperties": {
+                  "$ref": "#/$defs/ContributeValue"
+                },
+                "type": "object"
+              }
+            ]
+          },
+          "title": "Contribute",
+          "type": "array"
+        },
+        "parser": {
+          "anyOf": [
+            {
+              "enum": [
+                "json",
+                "jsonl",
+                "yaml"
+              ],
+              "type": "string"
+            },
+            {
+              "$ref": "#/$defs/PdlParser"
+            },
+            {
+              "$ref": "#/$defs/RegexParser"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Parser to use to construct a value out of a string result.",
+          "title": "Parser"
+        },
+        "fallback": {
+          "anyOf": [
+            {
+              "type": "boolean"
+            },
+            {
+              "type": "integer"
+            },
+            {
+              "type": "number"
+            },
+            {
+              "type": "string"
+            },
+            {
+              "$ref": "#/$defs/FunctionBlock"
+            },
+            {
+              "$ref": "#/$defs/CallBlock"
+            },
+            {
+              "$ref": "#/$defs/LitellmModelBlock"
+            },
+            {
+              "$ref": "#/$defs/GraniteioModelBlock"
+            },
+            {
+              "$ref": "#/$defs/CodeBlock"
+            },
+            {
+              "$ref": "#/$defs/ArgsBlock"
+            },
+            {
+              "$ref": "#/$defs/GetBlock"
+            },
+            {
+              "$ref": "#/$defs/DataBlock"
+            },
+            {
+              "$ref": "#/$defs/IfBlock"
+            },
+            {
+              "$ref": "#/$defs/MatchBlock"
+            },
+            {
+              "$ref": "#/$defs/RepeatBlock"
+            },
+            {
+              "$ref": "#/$defs/TextBlock"
+            },
+            {
+              "$ref": "#/$defs/LastOfBlock"
+            },
+            {
+              "$ref": "#/$defs/ArrayBlock"
+            },
+            {
+              "$ref": "#/$defs/ObjectBlock"
+            },
+            {
+              "$ref": "#/$defs/MessageBlock"
+            },
+            {
+              "$ref": "#/$defs/ReadBlock"
+            },
+            {
+              "$ref": "#/$defs/IncludeBlock"
+            },
+            {
+              "$ref": "#/$defs/ImportBlock"
+            },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
+            {
+              "$ref": "#/$defs/ErrorBlock"
+            },
+            {
+              "$ref": "#/$defs/EmptyBlock"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Block to execute in case of error.\n    ",
+          "title": "Fallback"
+        },
+        "retry": {
+          "anyOf": [
+            {
+              "type": "integer"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "The maximum number of times to retry when an error occurs within a block.\n    ",
+          "title": "Retry"
+        },
+        "trace_error_on_retry": {
+          "anyOf": [
+            {
+              "type": "boolean"
+            },
+            {
+              "type": "string"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Whether to add the errors while retrying to the trace. Set this to true to use retry feature for multiple LLM trials.\n    ",
+          "title": "Trace Error On Retry"
+        },
+        "role": {
+          "anyOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Role associated to the block and sub-blocks.\nTypical roles are `system`, `user`, and `assistant`,\nbut there may be other roles such as `available_tools`.",
+          "title": "Role"
+        },
+        "pdl__context": {
+          "anyOf": [
+            {
+              "items": {
+                "additionalProperties": true,
+                "type": "object"
+              },
+              "type": "array"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": [],
+          "description": "Current context\n    ",
+          "title": "Pdl  Context"
+        },
+        "pdl__id": {
+          "anyOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": "",
+          "description": "Unique identifier for this block\n    ",
+          "title": "Pdl  Id"
+        },
+        "pdl__result": {
+          "anyOf": [
+            {},
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Result of the execution of the block",
+          "title": "Pdl  Result"
+        },
+        "pdl__location": {
+          "anyOf": [
+            {
+              "$ref": "#/$defs/PdlLocationType"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null
+        },
+        "pdl__timing": {
+          "anyOf": [
+            {
+              "$ref": "#/$defs/PdlTiming"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null
+        },
+        "pdl__is_leaf": {
+          "const": true,
+          "default": true,
+          "title": "Pdl  Is Leaf",
+          "type": "boolean"
+        },
+        "kind": {
+          "const": "aggregator",
+          "default": "aggregator",
+          "title": "Kind",
+          "type": "string"
+        },
+        "aggregator": {
+          "anyOf": [
+            {
+              "const": "context",
+              "type": "string"
+            },
+            {
+              "$ref": "#/$defs/FileAggregatorConfig"
+            }
+          ],
+          "title": "Aggregator"
+        }
+      },
+      "required": [
+        "aggregator"
+      ],
+      "title": "AggregatorBlock",
+      "type": "object"
+    },
     "AnyPattern": {
       "additionalProperties": false,
       "description": "Match any value.",
@@ -122,6 +521,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -162,6 +564,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -268,6 +673,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -521,6 +929,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -561,6 +972,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -667,6 +1081,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -875,6 +1292,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -1048,6 +1468,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -1088,6 +1511,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -1194,6 +1620,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -1425,6 +1854,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -1539,6 +1971,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -1579,6 +2014,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -1685,6 +2123,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -1899,6 +2340,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -1924,7 +2368,9 @@
       "description": "Values allowed in the `contribute` field.",
       "enum": [
         "result",
-        "context"
+        "context",
+        "stdout",
+        "stderr"
       ],
       "title": "ContributeTarget",
       "type": "string"
@@ -1938,10 +2384,7 @@
             {
               "$ref": "#/$defs/LocalizedExpression_TypeVar_"
             },
-            {
-              "items": {},
-              "type": "array"
-            },
+            {},
             {
               "type": "string"
             }
@@ -2049,6 +2492,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -2089,6 +2535,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -2195,6 +2644,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -2446,6 +2898,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -2486,6 +2941,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -2592,6 +3050,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -2837,6 +3298,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -2877,6 +3341,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -2983,6 +3450,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -3190,6 +3660,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -3211,6 +3684,112 @@
       "title": "ErrorBlock",
       "type": "object"
     },
+    "FileAggregatorConfig": {
+      "additionalProperties": false,
+      "properties": {
+        "description": {
+          "anyOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Documentation associated to the aggregator config.\n    ",
+          "title": "Description"
+        },
+        "file": {
+          "anyOf": [
+            {
+              "$ref": "#/$defs/LocalizedExpression_TypeVar_"
+            },
+            {
+              "type": "string"
+            }
+          ],
+          "description": "Name of the file to which contribute.",
+          "title": "File"
+        },
+        "mode": {
+          "anyOf": [
+            {
+              "$ref": "#/$defs/LocalizedExpression_TypeVar_"
+            },
+            {
+              "type": "string"
+            }
+          ],
+          "default": "w",
+          "description": "File opening mode.",
+          "title": "Mode"
+        },
+        "encoding": {
+          "anyOf": [
+            {
+              "$ref": "#/$defs/LocalizedExpression_TypeVar_"
+            },
+            {
+              "type": "string"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": "utf-8",
+          "description": "File encoding.",
+          "title": "Encoding"
+        },
+        "prefix": {
+          "anyOf": [
+            {
+              "$ref": "#/$defs/LocalizedExpression_TypeVar_"
+            },
+            {
+              "type": "string"
+            }
+          ],
+          "default": "",
+          "description": "Prefix to the contributed value.",
+          "title": "Prefix"
+        },
+        "suffix": {
+          "anyOf": [
+            {
+              "$ref": "#/$defs/LocalizedExpression_TypeVar_"
+            },
+            {
+              "type": "string"
+            }
+          ],
+          "default": "\n",
+          "description": "Suffix to the contributed value.",
+          "title": "Suffix"
+        },
+        "flush": {
+          "anyOf": [
+            {
+              "$ref": "#/$defs/LocalizedExpression_TypeVar_"
+            },
+            {
+              "type": "boolean"
+            },
+            {
+              "type": "string"
+            }
+          ],
+          "default": false,
+          "description": "Whether to forcibly flush the stream.",
+          "title": "Flush"
+        }
+      },
+      "required": [
+        "file"
+      ],
+      "title": "FileAggregatorConfig",
+      "type": "object"
+    },
     "FunctionBlock": {
       "additionalProperties": false,
       "description": "Function declaration.",
@@ -3305,6 +3884,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -3345,6 +3927,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -3451,6 +4036,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -3668,6 +4256,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -3798,6 +4389,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -3838,6 +4432,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -3944,6 +4541,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -4181,6 +4781,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -4221,6 +4824,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -4327,6 +4933,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -4529,6 +5138,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -4783,6 +5395,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -4823,6 +5438,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -4929,6 +5547,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -5150,6 +5771,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -5234,6 +5858,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -5350,6 +5977,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -5390,6 +6020,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -5496,6 +6129,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -5703,6 +6339,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -5817,6 +6456,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -5857,6 +6499,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -5963,6 +6608,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -6174,6 +6822,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -6393,6 +7044,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -6433,6 +7087,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -6539,6 +7196,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -6747,6 +7407,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -6862,6 +7525,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -6902,6 +7568,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -7008,6 +7677,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -7210,6 +7882,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -7844,6 +8519,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -7884,6 +8562,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -7990,6 +8671,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -8280,6 +8964,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -8429,6 +9116,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -8469,6 +9159,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -8575,6 +9268,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -8777,6 +9473,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -8923,6 +9622,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -8963,6 +9665,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -9069,6 +9774,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -9278,6 +9986,9 @@
                   {
                     "$ref": "#/$defs/ImportBlock"
                   },
+                  {
+                    "$ref": "#/$defs/AggregatorBlock"
+                  },
                   {
                     "$ref": "#/$defs/ErrorBlock"
                   },
@@ -9363,6 +10074,9 @@
                   {
                     "$ref": "#/$defs/ImportBlock"
                   },
+                  {
+                    "$ref": "#/$defs/AggregatorBlock"
+                  },
                   {
                     "$ref": "#/$defs/ErrorBlock"
                   },
@@ -9605,6 +10319,9 @@
         {
           "$ref": "#/$defs/ImportBlock"
         },
+        {
+          "$ref": "#/$defs/AggregatorBlock"
+        },
         {
           "$ref": "#/$defs/ErrorBlock"
         },
@@ -9739,6 +10456,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -9965,6 +10685,9 @@
         {
           "$ref": "#/$defs/ImportBlock"
         },
+        {
+          "$ref": "#/$defs/AggregatorBlock"
+        },
         {
           "$ref": "#/$defs/ErrorBlock"
         },
@@ -10072,6 +10795,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -10112,6 +10838,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -10218,6 +10947,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -10527,6 +11259,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -10567,6 +11302,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -10673,6 +11411,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -10935,6 +11676,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -11079,6 +11823,9 @@
                   {
                     "$ref": "#/$defs/ImportBlock"
                   },
+                  {
+                    "$ref": "#/$defs/AggregatorBlock"
+                  },
                   {
                     "$ref": "#/$defs/ErrorBlock"
                   },
@@ -11200,6 +11947,9 @@
               {
                 "$ref": "#/$defs/ImportBlock"
               },
+              {
+                "$ref": "#/$defs/AggregatorBlock"
+              },
               {
                 "$ref": "#/$defs/ErrorBlock"
               },
@@ -11240,6 +11990,9 @@
               {
                 "$ref": "#/$defs/ContributeTarget"
               },
+              {
+                "type": "string"
+              },
               {
                 "additionalProperties": {
                   "$ref": "#/$defs/ContributeValue"
@@ -11346,6 +12099,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -11552,6 +12308,9 @@
             {
               "$ref": "#/$defs/ImportBlock"
             },
+            {
+              "$ref": "#/$defs/AggregatorBlock"
+            },
             {
               "$ref": "#/$defs/ErrorBlock"
             },
@@ -11630,6 +12389,9 @@
                   {
                     "$ref": "#/$defs/ImportBlock"
                   },
+                  {
+                    "$ref": "#/$defs/AggregatorBlock"
+                  },
                   {
                     "$ref": "#/$defs/ErrorBlock"
                   },
diff --git a/src/pdl/pdl_ast.py b/src/pdl/pdl_ast.py
index 396fe7570..550352291 100644
--- a/src/pdl/pdl_ast.py
+++ b/src/pdl/pdl_ast.py
@@ -65,6 +65,7 @@ class BlockKind(StrEnum):
     READ = "read"
     INCLUDE = "include"
     IMPORT = "import"
+    AGGREGATOR = "aggregator"
     EMPTY = "empty"
     ERROR = "error"
 
@@ -272,6 +273,8 @@ class ContributeTarget(StrEnum):
 
     RESULT = "result"
     CONTEXT = "context"
+    STDOUT = "stdout"
+    STDERR = "stderr"
 
 
 class ContributeValue(BaseModel):
@@ -279,10 +282,13 @@ class ContributeValue(BaseModel):
 
     model_config = ConfigDict(extra="forbid")
 
-    value: ExpressionType[list[Any]]
+    value: ExpressionType[Any]
     """Value to contribute."""
 
 
+ContributeElement: TypeAlias = ContributeTarget | str | dict[str, ContributeValue]
+
+
 class PdlTiming(BaseModel):
     """Internal data structure to record timing information in the trace."""
 
@@ -333,7 +339,7 @@ class Block(BaseModel):
     def_: Optional[str] = Field(default=None, alias="def")
     """Name of the variable used to store the result of the execution of the block.
     """
-    contribute: Sequence[ContributeTarget | dict[str, ContributeValue]] = [
+    contribute: Sequence[ContributeElement] = [
         ContributeTarget.RESULT,
         ContributeTarget.CONTEXT,
     ]
@@ -944,6 +950,45 @@ class ImportBlock(LeafBlock):
     pdl__trace: Optional["BlockType"] = None
 
 
+class AggregatorConfig(BaseModel):
+    """Common fields for all aggregator configurations."""
+
+    model_config = ConfigDict(
+        extra="forbid",
+        use_attribute_docstrings=True,
+        arbitrary_types_allowed=True,
+    )
+
+    description: Optional[str] = None
+    """Documentation associated to the aggregator config.
+    """
+
+
+class FileAggregatorConfig(AggregatorConfig):
+    file: ExpressionType[str]
+    """Name of the file to which contribute."""
+    mode: ExpressionType[str] = "w"
+    """File opening mode."""
+    encoding: ExpressionType[Optional[str]] = "utf-8"
+    """File encoding."""
+    prefix: ExpressionType[str] = ""
+    """Prefix to the contributed value."""
+    suffix: ExpressionType[str] = "\n"
+    """Suffix to the contributed value."""
+    flush: ExpressionType[bool] = False
+    """Whether to forcibly flush the stream."""
+
+
+AggregatorType: TypeAlias = Literal["context"] | FileAggregatorConfig
+
+
+class AggregatorBlock(LeafBlock):
+    """Create a new aggregator that can be use in the `contribute` field."""
+
+    kind: Literal[BlockKind.AGGREGATOR] = BlockKind.AGGREGATOR
+    aggregator: AggregatorType
+
+
 class ErrorBlock(LeafBlock):
     """Block representing an error generated at runtime."""
 
@@ -982,6 +1027,7 @@ class EmptyBlock(LeafBlock):
     | ReadBlock
     | IncludeBlock
     | ImportBlock
+    | AggregatorBlock
     | ErrorBlock
     | EmptyBlock
 )
diff --git a/src/pdl/pdl_ast_utils.py b/src/pdl/pdl_ast_utils.py
index 241662680..3a775b7ca 100644
--- a/src/pdl/pdl_ast_utils.py
+++ b/src/pdl/pdl_ast_utils.py
@@ -1,6 +1,7 @@
 from typing import Callable, Sequence
 
 from .pdl_ast import (
+    AggregatorBlock,
     ArrayBlock,
     Block,
     BlockType,
@@ -95,6 +96,8 @@ def iter_block_children(f: Callable[[BlockType], None], block: BlockType) -> Non
         case ImportBlock():
             if block.pdl__trace is not None:
                 f(block.pdl__trace)
+        case AggregatorBlock():
+            pass
         case EmptyBlock():
             pass
         case _:
@@ -201,6 +204,8 @@ def map_block_children(f: MappedFunctions, block: BlockType) -> BlockType:
         case ImportBlock():
             if block.pdl__trace is not None:
                 block.pdl__trace = f.f_block(block.pdl__trace)
+        case AggregatorBlock():
+            pass
         case EmptyBlock():
             pass
         case _:
diff --git a/src/pdl/pdl_compilers/to_regex.py b/src/pdl/pdl_compilers/to_regex.py
index 602e81a0c..3b61b8930 100644
--- a/src/pdl/pdl_compilers/to_regex.py
+++ b/src/pdl/pdl_compilers/to_regex.py
@@ -4,6 +4,7 @@
 from typing import Sequence, TypeAlias
 
 from ..pdl_ast import (
+    AggregatorBlock,
     Block,
     BlockType,
     CallBlock,
@@ -318,6 +319,8 @@ def compile_block(
             regex = ReStar(ReAnyChar())  # XXX TODO XXX
         case ImportBlock():
             regex = ReStar(ReAnyChar())  # XXX TODO XXX
+        case AggregatorBlock():
+            regex = ReStar(ReAnyChar())  # XXX TODO XXX
         case FunctionBlock():
             regex = ReStar(ReAnyChar())  # XXX TODO XXX
             # scope = scope | {x: ReStar(ReAnyChar) for x in block.function.keys()}
diff --git a/src/pdl/pdl_dumper.py b/src/pdl/pdl_dumper.py
index bcd3f9379..341e22a9d 100644
--- a/src/pdl/pdl_dumper.py
+++ b/src/pdl/pdl_dumper.py
@@ -8,6 +8,8 @@
 
 from . import pdl_ast
 from .pdl_ast import (
+    AggregatorBlock,
+    AggregatorType,
     AnyPattern,
     ArgsBlock,
     ArrayBlock,
@@ -15,13 +17,14 @@
     Block,
     CallBlock,
     CodeBlock,
+    ContributeElement,
     ContributeTarget,
-    ContributeValue,
     DataBlock,
     EmptyBlock,
     EnumPdlType,
     ErrorBlock,
     ExpressionType,
+    FileAggregatorConfig,
     FunctionBlock,
     GetBlock,
     GraniteioModelBlock,
@@ -213,6 +216,8 @@ def block_to_dict(  # noqa: C901
             d["import"] = block.import_
             if block.pdl__trace:
                 d["pdl__trace"] = block_to_dict(block.pdl__trace, json_compatible)
+        case AggregatorBlock():
+            d["aggregator"] = aggregator_to_dict(block.aggregator)
         case IfBlock():
             d["if"] = expr_to_dict(block.condition, json_compatible)
             d["then"] = block_to_dict(block.then, json_compatible)
@@ -453,7 +458,7 @@ def location_to_dict(location: PdlLocationType) -> dict[str, Any]:
 
 
 def contribute_to_list(
-    contribute: Sequence[ContributeTarget | dict[str, ContributeValue]],
+    contribute: Sequence[ContributeElement],
 ) -> list[str | dict[str, Any]]:
     acc: list[str | dict[str, Any]] = []
     for contrib in contribute:
@@ -464,6 +469,17 @@ def contribute_to_list(
     return acc
 
 
+def aggregator_to_dict(aggregator: AggregatorType):
+    match aggregator:
+        case "context":
+            result = aggregator
+        case FileAggregatorConfig():
+            result = aggregator.model_dump()
+        case _:
+            assert False, "Unexpected aggregator"
+    return result
+
+
 def build_exclude(obj: Any, regex: re.Pattern[str]) -> Any:
     if isinstance(obj, BaseModel):
         exclude: dict[str, Any] = {}
diff --git a/src/pdl/pdl_interpreter.py b/src/pdl/pdl_interpreter.py
index 85fe87041..fc9b89ee2 100644
--- a/src/pdl/pdl_interpreter.py
+++ b/src/pdl/pdl_interpreter.py
@@ -10,6 +10,7 @@
 
 # TODO: temporarily disabling warnings to mute a pydantic warning from liteLLM
 import warnings
+from abc import ABC, abstractmethod
 from asyncio import AbstractEventLoop
 from functools import partial
 from os import getenv
@@ -17,7 +18,7 @@
 warnings.filterwarnings("ignore", "Valid config keys have changed in V2")
 
 from pathlib import Path  # noqa: E402
-from typing import Any, Generator, Optional, Sequence, TypeVar  # noqa: E402
+from typing import IO, Any, Generator, Optional, Sequence, TypeVar  # noqa: E402
 
 import httpx  # noqa: E402
 import json_repair  # noqa: E402
@@ -36,6 +37,7 @@
 
 from .pdl_ast import (  # noqa: E402
     AdvancedBlockType,
+    AggregatorBlock,
     AnyPattern,
     ArgsBlock,
     ArrayBlock,
@@ -45,12 +47,14 @@
     BlockType,
     CallBlock,
     CodeBlock,
+    ContributeElement,
     ContributeTarget,
     ContributeValue,
     DataBlock,
     EmptyBlock,
     ErrorBlock,
     ExpressionType,
+    FileAggregatorConfig,
     FunctionBlock,
     GetBlock,
     GraniteioModelBlock,
@@ -63,6 +67,7 @@
     LastOfBlock,
     LazyMessage,
     LazyMessages,
+    LeafBlock,
     LitellmModelBlock,
     LitellmParameters,
     LocalizedExpression,
@@ -121,7 +126,7 @@
 from .pdl_utils import (  # noqa: E402
     GeneratorWrapper,
     apply_defaults,
-    get_contribute_value,
+    get_contribute_context_value,
     replace_contribute_value,
     stringify,
     value_of_expr,
@@ -304,7 +309,7 @@ def process_block(
 def context_in_contribute(block: AdvancedBlockType) -> bool:
     if ContributeTarget.CONTEXT.value in block.contribute:
         return True
-    if get_contribute_value(block.contribute) is not None:
+    if get_contribute_context_value(block.contribute) is not None:
         return True
     return False
 
@@ -391,7 +396,7 @@ def process_advanced_block(
     init_state = state
     state = state.with_yield_result(
         state.yield_result
-        and ContributeTarget.RESULT in block.contribute
+        and ContributeTarget.RESULT.value in block.contribute
         and block.parser is None
     )
     state = state.with_yield_background(
@@ -417,13 +422,11 @@ def process_advanced_block(
             )
             trace = trace.model_copy(update={"pdl__result": result})
             if block.parser is not None:
-                # Use partial to create a function with fixed arguments
                 parser_func = partial(parse_result, block.parser)
                 result = lazy_apply(parser_func, result)
-                if init_state.yield_result and ContributeTarget.RESULT:
+                if init_state.yield_result:
                     yield_result(result, block.kind)
             if block.spec is not None and not isinstance(block, FunctionBlock):
-                # Use partial to create a function with fixed arguments
                 checker = partial(
                     result_with_type_checking,
                     spec=block.spec,
@@ -479,14 +482,15 @@ def process_advanced_block(
     if block.def_ is not None:
         var = block.def_
         new_scope = new_scope | PdlDict({var: result})
-    if ContributeTarget.RESULT not in block.contribute:
-        result = PdlConst("")
-    if ContributeTarget.CONTEXT not in block.contribute:
+    new_scope, trace = process_contribute(trace, result, new_scope, loc)
+    if ContributeTarget.CONTEXT.value not in block.contribute:
         background = DependentContext([])
-    contribute_value, trace = process_contribute(trace, new_scope, loc)
-    if contribute_value is not None:
-        background = DependentContext([contribute_value])
-
+    else:
+        contribute_value, trace = process_contribute_context(trace, new_scope, loc)
+        if contribute_value is not None:
+            background = DependentContext([contribute_value])
+    if ContributeTarget.RESULT.value not in block.contribute:
+        result = PdlConst("")
     return result, background, new_scope, trace
 
 
@@ -908,6 +912,11 @@ def process_block_body(
         case ImportBlock():
             result, background, scope, trace = process_import(state, scope, block, loc)
 
+        case AggregatorBlock():
+            result, background, scope, trace = process_aggregator(
+                state, scope, block, loc
+            )
+
         case FunctionBlock():
             closure = block.model_copy()
             if block.def_ is not None:
@@ -1182,19 +1191,17 @@ def combine_results(iteration_type: IterationType, results: list[PdlLazy[Any]]):
     return result
 
 
-BlockTypeTVarProcessContribute = TypeVar(
-    "BlockTypeTVarProcessContribute", bound=AdvancedBlockType
+BlockTypeTVarProcessContributeOld = TypeVar(
+    "BlockTypeTVarProcessContributeOld", bound=AdvancedBlockType
 )
 
 
-def process_contribute(
-    block: BlockTypeTVarProcessContribute, scope: ScopeType, loc: PdlLocationType
-) -> tuple[Any, BlockTypeTVarProcessContribute]:
-    result: list[ContributeTarget | dict[str, ContributeValue]]
-    value_trace: LocalizedExpression[
-        list[ContributeTarget | dict[str, ContributeValue]]
-    ]
-    value = get_contribute_value(block.contribute)
+def process_contribute_context(
+    block: BlockTypeTVarProcessContributeOld, scope: ScopeType, loc: PdlLocationType
+) -> tuple[Any, BlockTypeTVarProcessContributeOld]:
+    result: list[ContributeElement]
+    value_trace: LocalizedExpression[list[ContributeElement]]
+    value = get_contribute_context_value(block.contribute)
     if value is None:
         return None, block
     loc = append(loc, "contribute")
@@ -1213,6 +1220,74 @@ def process_contribute(
     return result, trace
 
 
+BlockTypeTVarProcessContribute = TypeVar(
+    "BlockTypeTVarProcessContribute", bound=AdvancedBlockType
+)
+
+
+def process_contribute(
+    block: BlockTypeTVarProcessContribute,
+    result: Any,
+    scope: ScopeType,
+    loc: PdlLocationType,
+) -> tuple[ScopeType, BlockTypeTVarProcessContribute]:
+    loc = append(loc, "contribute")
+    contribute = []
+    for i, elem in enumerate(block.contribute):
+        scope, elem = process_contribution(
+            block, elem, result, scope, append(loc, "[" + str(i) + "]")
+        )
+        contribute.append(elem)
+    trace = block.model_copy(update={"contribute": contribute})
+    return scope, trace
+
+
+def process_contribution(
+    block: AdvancedBlockType,
+    elem: ContributeElement,
+    result: Any,
+    scope: ScopeType,
+    loc: PdlLocationType,
+) -> tuple[ScopeType, ContributeElement]:
+    target: ContributeTarget | str
+    match elem:
+        case ContributeTarget.RESULT | "result" | ContributeTarget.CONTEXT | "context":
+            return scope, elem
+        case ContributeTarget() | str():
+            target = elem
+        case dict():
+            if len(elem) != 1:
+                msg = "Contributions are expected to be strings or dictionaries of length 1 but got {elem}"
+                raise PDLRuntimeError(
+                    msg,
+                    loc=loc,
+                    trace=ErrorBlock(msg=msg, pdl__location=loc, program=block),
+                    fallback=[],
+                )
+            target, contribute_value = list(elem.items()).pop()
+            try:
+                result, value_trace = process_expr(scope, contribute_value.value, loc)
+            except PDLRuntimeExpressionError as exc:
+                raise PDLRuntimeError(
+                    exc.message,
+                    loc=exc.loc or loc,
+                    trace=ErrorBlock(msg=exc.message, pdl__location=loc, program=block),
+                ) from exc
+            elem = {target: ContributeValue(value=value_trace)}
+        case _:
+            msg = "Contributions are expected to be strings or dictionaries of length 1 but got {elem}"
+            raise PDLRuntimeError(
+                msg,
+                loc=loc,
+                trace=ErrorBlock(msg=msg, pdl__location=loc, program=block),
+                fallback=[],
+            )
+    aggregator = get_contribute_aggregator(block, target, scope, loc)
+    aggregator = aggregator.contribute(result, block.role, loc, block)
+    scope = scope | {target: aggregator}
+    return scope, elem
+
+
 BlockTypeTVarProcessExprOf = TypeVar(
     "BlockTypeTVarProcessExprOf", bound=AdvancedBlockType
 )
@@ -2038,6 +2113,163 @@ def process_import(
         ) from exc
 
 
+class Aggregator(ABC):
+    @abstractmethod
+    def contribute(
+        self,
+        result: PdlLazy[Any],
+        role: Optional[RoleType] = None,
+        loc: Optional[PdlLocationType] = None,
+        block: Optional[BlockType] = None,
+    ) -> "Aggregator":
+        """Function executed at the end of each block that contain the aggregator.
+
+        Args:
+            result: value computed by the block
+            role: role associated to the block. Defaults to None.
+            loc: source code location of the block. Defaults to None.
+            block: block contributing the value. Defaults to None.
+
+        Returns:
+            Aggregator: new aggregator with the contributed value.
+        """
+
+
+class ContextAggregator(Aggregator):
+    def __init__(self, messages: Optional[LazyMessages] = None):
+        if messages is None:
+            self.messages: LazyMessages = DependentContext([])
+        else:
+            self.messages = messages
+
+    def contribute(
+        self,
+        result: PdlLazy[Any],
+        role: Optional[RoleType] = None,
+        loc: Optional[PdlLocationType] = None,
+        block: Optional[BlockType] = None,
+    ) -> "ContextAggregator":
+        match block:
+            case None | StructuredBlock():
+                return self
+            case LeafBlock():
+                block_id = ".".join(block.pdl__id or [])
+                msg = {"role": role, "content": result, "pdl__defsite": block_id}
+            case _:
+                msg = {"role": role, "content": result}
+        new_messages: LazyMessages = SingletonContext(PdlDict(msg))
+        messages = DependentContext([self.messages, new_messages])
+        return ContextAggregator(messages)
+
+
+class FileAggregator(Aggregator):
+    def __init__(
+        self, fp: IO, prefix: str = "", suffix: str = "\n", flush: bool = False
+    ):
+        self.fp = fp
+        self.prefix = prefix
+        self.suffix = suffix
+        self.flush = flush
+
+    def contribute(
+        self,
+        result: PdlLazy[Any],
+        role: Optional[RoleType] = None,
+        loc: Optional[PdlLocationType] = None,
+        block: Optional[BlockType] = None,
+    ) -> "FileAggregator":
+        print(f"{self.prefix}{result}", file=self.fp, end=self.suffix, flush=self.flush)
+        return self
+
+
+def process_aggregator(
+    state: InterpreterState,
+    scope: ScopeType,
+    block: AggregatorBlock,
+    loc: PdlLocationType,
+) -> tuple[PdlLazy[Aggregator], LazyMessages, ScopeType, AggregatorBlock]:
+    aggregator: Aggregator
+    match block.aggregator:
+        case "context":
+            aggregator = ContextAggregator()
+        case FileAggregatorConfig():
+            try:
+                cfg = block.aggregator
+                file: str
+                file_trace: ExpressionType[str]
+                file, file_trace = process_expr(scope, cfg.file, loc)
+                mode: str
+                mode_trace: ExpressionType[str]
+                mode, mode_trace = process_expr(scope, cfg.mode, loc)
+                encoding: Optional[str]
+                encoding_trace: ExpressionType[Optional[str]]
+                encoding, encoding_trace = process_expr(scope, cfg.encoding, loc)
+                prefix: str
+                prefix_trace: ExpressionType[str]
+                prefix, prefix_trace = process_expr(scope, cfg.prefix, loc)
+                suffix: str
+                suffix_trace: ExpressionType[str]
+                suffix, suffix_trace = process_expr(scope, cfg.suffix, loc)
+                flush: bool
+                flush_trace: ExpressionType[bool]
+                flush, flush_trace = process_expr(scope, cfg.flush, loc)
+                cfg = block.aggregator.model_copy(
+                    update={
+                        "file": file_trace,
+                        "mode": mode_trace,
+                        "encoding": encoding_trace,
+                        "prefix": prefix_trace,
+                        "suffix": suffix_trace,
+                        "flush": flush_trace,
+                    }
+                )
+                trace = block.model_copy(update={"aggregator": cfg})
+            except PDLRuntimeExpressionError as exc:
+                raise PDLRuntimeError(
+                    exc.message,
+                    loc=exc.loc or loc,
+                    trace=ErrorBlock(msg=exc.message, pdl__location=loc, program=block),
+                ) from exc
+            fp = open(  # pylint: disable=consider-using-with
+                file, mode=mode, encoding=encoding
+            )
+            aggregator = FileAggregator(fp, prefix=prefix, suffix=suffix, flush=flush)
+        case _:
+            assert False, "Unexpected aggregator"
+    background: LazyMessages = DependentContext([])
+    trace = block.model_copy()
+    return PdlConst(aggregator), background, scope, trace
+
+
+def get_contribute_aggregator(
+    block: AdvancedBlockType,
+    target: ContributeTarget | str,
+    scope: ScopeType,
+    loc: PdlLocationType,
+) -> Aggregator:
+    match target:
+        case ContributeTarget.STDOUT | "stdout":
+            aggregator = FileAggregator(sys.stdout, flush=True)
+        case ContributeTarget.STDERR | "stderr":
+            aggregator = FileAggregator(sys.stderr, flush=True)
+        case str():
+            aggregator = get_var(target, scope, loc)
+            if isinstance(aggregator, PdlLazy):
+                aggregator = aggregator.result()
+            if not isinstance(aggregator, Aggregator):
+                msg = f"An aggregator was expected but got a value of type {type(aggregator)}."
+                raise PDLRuntimeError(
+                    msg,
+                    loc=loc,
+                    trace=ErrorBlock(msg=msg, pdl__location=loc, program=block),
+                    fallback=[],
+                )
+
+        case _:
+            assert False, f"Unexpected target type: {type(target)}"
+    return aggregator
+
+
 JSONReturnType = dict[str, Any] | list[Any] | str | float | int | bool | None
 
 
diff --git a/src/pdl/pdl_scheduler.py b/src/pdl/pdl_scheduler.py
index 5e126ae7f..909a54b95 100644
--- a/src/pdl/pdl_scheduler.py
+++ b/src/pdl/pdl_scheduler.py
@@ -57,6 +57,8 @@ def color_of(kind: BlockKind):
             color = None
         case BlockKind.IMPORT:
             color = None
+        case BlockKind.AGGREGATOR:
+            color = None
         case BlockKind.EMPTY:
             color = None
         case BlockKind.ERROR:
diff --git a/src/pdl/pdl_utils.py b/src/pdl/pdl_utils.py
index 59afcef39..47fd5e669 100644
--- a/src/pdl/pdl_utils.py
+++ b/src/pdl/pdl_utils.py
@@ -6,6 +6,7 @@
 
 from .pdl_ast import (
     BlockType,
+    ContributeElement,
     ContributeTarget,
     ContributeValue,
     ExpressionType,
@@ -81,8 +82,8 @@ def value_of_expr(expr: ExpressionType[ValueOfExprT]) -> ValueOfExprT:
     return v  # type: ignore
 
 
-def replace_contribute_value(
-    contribute: Sequence[ContributeTarget | dict[str, ContributeValue]],
+def replace_contribute_value(  # TODO: remove
+    contribute: Sequence[ContributeElement],
     value: ContributeValue,
 ):
     ret = []
@@ -95,14 +96,14 @@ def replace_contribute_value(
     return ret
 
 
-def get_contribute_value(
-    contribute: Sequence[ContributeTarget | dict[str, ContributeValue]] | None,
+def get_contribute_context_value(
+    contribute: Sequence[ContributeElement] | None,
 ):
     if contribute is None:
         return None
     for item in contribute:
         if isinstance(item, dict) and isinstance(
-            item[ContributeTarget.CONTEXT], ContributeValue
+            item.get(ContributeTarget.CONTEXT), ContributeValue
         ):
             return item[ContributeTarget.CONTEXT].value
     return None
diff --git a/tests/results/examples/aggregators/contribute_in_file.0.result b/tests/results/examples/aggregators/contribute_in_file.0.result
new file mode 100644
index 000000000..281fc3326
--- /dev/null
+++ b/tests/results/examples/aggregators/contribute_in_file.0.result
@@ -0,0 +1 @@
+HelloHello! How can I assist you today?nice to meet you.It's nice to meet you too! I'm here to help answer your questions or provide information on a wide range of topics. Please go ahead and ask.Bye
diff --git a/tests/results/examples/aggregators/contribute_in_stderr.0.result b/tests/results/examples/aggregators/contribute_in_stderr.0.result
new file mode 100644
index 000000000..5cd085a9f
--- /dev/null
+++ b/tests/results/examples/aggregators/contribute_in_stderr.0.result
@@ -0,0 +1 @@
+HelloHello! How can I assist you today?
diff --git a/tests/results/examples/aggregators/contribute_in_stdout.0.result b/tests/results/examples/aggregators/contribute_in_stdout.0.result
new file mode 100644
index 000000000..5cd085a9f
--- /dev/null
+++ b/tests/results/examples/aggregators/contribute_in_stdout.0.result
@@ -0,0 +1 @@
+HelloHello! How can I assist you today?