diff --git a/pdl-live-react/src/pdl_ast.d.ts b/pdl-live-react/src/pdl_ast.d.ts
index 1e3bec9c6..12f8123d3 100644
--- a/pdl-live-react/src/pdl_ast.d.ts
+++ b/pdl-live-react/src/pdl_ast.d.ts
@@ -2354,6 +2354,11 @@ export type PdlContext17 =
 export type PdlId17 = string | null
 export type PdlIsLeaf17 = true
 export type Kind17 = "model"
+/**
+ * Model name used by the backend.
+ *
+ */
+export type Model = LocalizedExpression | string
 /**
  * Messages to send to the model.
  *
@@ -2411,11 +2416,6 @@ export type Backend =
   | {
       [k: string]: unknown
     }
-/**
- * IO Processor name.
- *
- */
-export type Processor = LocalizedExpression | string | null
 /**
  * Parameters sent to the model.
  *
@@ -3210,7 +3210,7 @@ export interface GraniteioModelBlock {
   pdl__timing?: PdlTiming | null
   pdl__is_leaf?: PdlIsLeaf17
   kind?: Kind17
-  model: unknown
+  model: Model
   input?: Input
   modelResponse?: Modelresponse
   /**
@@ -3221,7 +3221,7 @@ export interface GraniteioModelBlock {
   pdl__model_input?: PdlModelInput
   platform?: Platform
   backend: Backend
-  processor?: Processor
+  processor?: unknown
   parameters?: Parameters
 }
 /**
diff --git a/pdl-live-react/src/pdl_ast_utils.ts b/pdl-live-react/src/pdl_ast_utils.ts
index 8326e798c..541c3c048 100644
--- a/pdl-live-react/src/pdl_ast_utils.ts
+++ b/pdl-live-react/src/pdl_ast_utils.ts
@@ -1,6 +1,6 @@
 import { match, P } from "ts-pattern"
 
-import { Backend, PdlBlock, Processor } from "./pdl_ast"
+import { Backend, PdlBlock } from "./pdl_ast"
 import { ExpressionT, isArgs } from "./helpers"
 
 export function map_block_children(
@@ -74,10 +74,7 @@ export function map_block_children(
           : undefined
         // @ts-expect-error: f_expr does not preserve the type of the expression
         const backend: Backend = f_expr(block.backend)
-        // @ts-expect-error: f_expr does not preserve the type of the expression
-        const processor: Processor = block.processor
-          ? f_expr(block.processor)
-          : undefined
+        const processor = block.processor ? f_expr(block.processor) : undefined
         return {
           ...block,
           model,
diff --git a/src/pdl/pdl-schema.json b/src/pdl/pdl-schema.json
index 74b2e5775..bd4e9b2c2 100644
--- a/src/pdl/pdl-schema.json
+++ b/src/pdl/pdl-schema.json
@@ -4461,7 +4461,6 @@
             {
               "$ref": "#/$defs/LocalizedExpression_TypeVar_"
             },
-            {},
             {
               "type": "string"
             }
@@ -4626,6 +4625,7 @@
             {
               "type": "string"
             },
+            {},
             {
               "type": "null"
             }
diff --git a/src/pdl/pdl_ast.py b/src/pdl/pdl_ast.py
index 577518d27..b5294ab04 100644
--- a/src/pdl/pdl_ast.py
+++ b/src/pdl/pdl_ast.py
@@ -548,13 +548,13 @@ class GraniteioModelBlock(ModelBlock):
     platform: Literal[ModelPlatform.GRANITEIO] = ModelPlatform.GRANITEIO
     """Optional field to ensure that the block is using granite-io.
     """
-    model: ExpressionType[object]
+    model: ExpressionType[str]
     """Model name used by the backend.
     """
-    backend: ExpressionType[str | dict[str, Any]]
+    backend: ExpressionType[str | dict[str, Any | object]]
     """Backend name and configuration.
     """
-    processor: Optional[ExpressionType[str]] = None
+    processor: Optional[ExpressionType[str | object]] = None
     """IO Processor name.
     """
     parameters: Optional[ExpressionType[dict[str, Any]]] = None
diff --git a/src/pdl/pdl_granite_io.py b/src/pdl/pdl_granite_io.py
index adce5d309..4690e11ee 100644
--- a/src/pdl/pdl_granite_io.py
+++ b/src/pdl/pdl_granite_io.py
@@ -19,17 +19,18 @@
 class GraniteioModel:
     @staticmethod
     def processor_of_block(block: GraniteioModelBlock):
-        model = value_of_expr(block.model)
+        from granite_io import make_backend, make_io_processor
+        from granite_io.backend.base import Backend
+        from granite_io.io import InputOutputProcessor
+
+        processor = value_of_expr(block.processor)
+        if isinstance(processor, InputOutputProcessor):
+            return processor
+        model: str = value_of_expr(block.model)
         backend = value_of_expr(block.backend)
         assert isinstance(model, str), f"The model should be a string: {model}"
-        assert isinstance(
-            backend, (dict, str)
-        ), f"The backend should be a string or a dictionary: {backend}"
         match backend:
             case {"transformers": device}:
-                assert isinstance(backend, dict)
-                from granite_io import make_backend
-
                 backend = make_backend(
                     "transformers",
                     {
@@ -37,26 +38,27 @@ def processor_of_block(block: GraniteioModelBlock):
                         "device": device,
                     },
                 )
-            case backend_name if isinstance(backend_name, str):
-                from granite_io import make_backend
-
+            case str():
                 backend = make_backend(
-                    backend_name,
+                    backend,
                     {
                         "model_name": model,
                     },
                 )
+            case Backend():
+                pass
             case _:
                 assert False, f"Unexpected backend: {backend}"
-        if block.processor is None:
+        if processor is None:
             processor_name = model
         else:
-            processor_name = value_of_expr(block.processor)
+            assert isinstance(
+                processor, str
+            ), f"The processor should be a string: {processor}"
+            processor_name = value_of_expr(processor)
         assert isinstance(
             processor_name, str
         ), f"The processor should be a string: {processor_name}"
-        from granite_io import make_io_processor
-
         io_processor = make_io_processor(processor_name, backend=backend)
         return io_processor
 
@@ -87,7 +89,7 @@ async def async_generate_text(
                 inputs
             )
             try:  # TODO: update when new version of granite-io is released
-                message = result.next_message.model_dump()
+                message = result.next_message.model_dump()  # pyright: ignore
             except AttributeError:
                 message = result.results[0].next_message.model_dump()
             raw_result = result.model_dump()