Add support for file change diffs on tool call.

Author: ericdallo

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- Support custom system prompts via config `systemPromptTemplate`.
+- Add support for file change diffs on `eca_edit_file` tool call.
+
 ## 0.15.3
 
 - Rename `eca_list_directory` to `eca_directory_tree` tool for better overview of project files/dirs.

deps.edn

@@ -8,6 +8,7 @@
         babashka/fs {:mvn/version "0.5.26"}
         hato/hato {:mvn/version "1.0.0"}
         org.slf4j/slf4j-simple {:mvn/version "2.0.17"}
+        com.googlecode.java-diff-utils/diffutils {:mvn/version "1.3.0"}
         cheshire/cheshire {:mvn/version "6.0.0"}}
  :aliases
  {:dev {:extra-paths ["dev"]

docs/configuration.md

@@ -132,6 +132,7 @@ interface Config {
     openaiApiKey?: string;
     anthropicApiKey?: string;
     rules: [{path: string;}];
+    systemPromptTemplate?: string;
     nativeTools: {
         filesystem: {enabled: boolean};
          shell: {enabled: boolean;

docs/protocol.md

@@ -293,10 +293,12 @@ interface FileContext {
     /**
      * Range of lines to retrive from file, if nil consider whole file.
      */
-    linesRange?: {
-        start: number;
-        end: number;
-    }
+    linesRange?: LinesRange;
+}
+
+interface LinesRange {
+   start: number;
+   end: number;
 }
 
 /**
@@ -601,6 +603,38 @@ interface ToolCallRunContent {
      * Whether this call requires manual approval from the user.
      */
     manualApproval: boolean;
+    
+    /**
+     * Extra details about this call. 
+     * Clients may use this to present different UX for this tool call.
+     */
+    details?: TooCallRunDetails;
+}
+
+type TooCallRunDetails = FileChangeDetails;
+
+interface FileChangeDetails {
+    type: 'fileChange';
+
+     /**
+      * The file path of this file change
+      */
+     path: string;
+     
+     /**
+      * The content diff of this file change
+      */
+     diff: string;
+     
+     /**
+      * The count of lines added in this change.
+      */
+     linesAdded: number;
+     
+     /**
+      * The count of lines removed in this change.
+      */
+     linesRemoved: number;
 }
 
 /**

resources/eca_prompt.txt

@@ -10,6 +10,14 @@ When using markdown in assistant messages, use backticks to format file, directo
 Pay attention to the langauge name after the code block backticks start, use the full language name like 'javascript' instead of 'js'.
 </communication>
 
+<edit_file_instructions>
+Before editing a file, ensure you have its content via the provided context or eca_read_file tool.
+Use the eca_edit_file tool to modify files.
+NEVER show the code edits to the user - only call the tool. The system will apply and display the edits.
+For each file, give a short description of what needs to be edited, then use the eca_edit_file tool. You can use the tool multiple times in a response, and you can keep writing text after using a tool.
+The eca_edit_file tool is very smart and can understand how to apply your edits to the user's files.
+</edit_file_instructions>
+
 <tool_calling>
 You have tools at your disposal to solve the coding task. Follow these rules regarding tool calls:
 1. ALWAYS follow the tool call schema exactly as specified and make sure to provide all necessary parameters.

src/eca/diff.clj

@@ -0,0 +1,51 @@
+(ns eca.diff
+  (:require
+   [clojure.string :as string]
+   [eca.shared :as shared])
+  (:import
+   [difflib
+    ChangeDelta
+    DeleteDelta
+    DiffUtils
+    InsertDelta]))
+
+(set! *warn-on-reflection* true)
+
+(defn ^:private lines
+  "Splits S on `\n` or `\r\n`."
+  [s]
+  (string/split-lines s))
+
+(defn ^:private unlines
+  "Joins SS strings coll using the system's line separator."
+  [ss]
+  (string/join shared/line-separator ss))
+
+(defn diff
+  ([original revised file]
+   (let [patch (DiffUtils/diff (lines original) (lines revised))
+         deltas (.getDeltas patch)
+         added (->> deltas
+                    (filter #(instance? InsertDelta %))
+                    (mapcat (fn [^InsertDelta delta]
+                              (.getLines (.getRevised delta))))
+                    count)
+         changed (->> deltas
+                      (filter #(instance? ChangeDelta %))
+                      (mapcat (fn [^ChangeDelta delta]
+                                (.getLines (.getRevised delta))))
+                      count)
+         removed (->> deltas
+                      (filter #(instance? DeleteDelta %))
+                      (mapcat (fn [^DeleteDelta delta]
+                                (.getLines (.getOriginal delta))))
+                      count)]
+     {:added (+ added changed)
+      :removed (+ removed changed)
+      :diff
+      (unlines (DiffUtils/generateUnifiedDiff
+                file
+                file
+                (lines original)
+                patch
+                3))})))

src/eca/features/chat.clj

@@ -34,11 +34,11 @@
                                          :content (llm-api/refine-file-context filename nil)}))))
               "repoMap" [{:type :repoMap}]
               "mcpResource" (mapv
-                              (fn [{:keys [text]}]
-                                {:type :mcpResource
-                                 :uri uri
-                                 :content text})
-                              (:contents (f.mcp/get-resource! uri db)))))
+                             (fn [{:keys [text]}]
+                               {:type :mcpResource
+                                :uri uri
+                                :content text})
+                             (:contents (f.mcp/get-resource! uri db)))))
           contexts))
 
 (defn default-model [db config]
@@ -146,7 +146,7 @@
         rules (f.rules/all config (:workspace-folders db))
         refined-contexts (raw-contexts->refined contexts db)
         repo-map* (delay (f.index/repo-map db {:as-string? true}))
-        instructions (f.prompt/build-instructions refined-contexts rules repo-map* (or behavior (:chat-default-behavior db)))
+        instructions (f.prompt/build-instructions refined-contexts rules repo-map* (or behavior (:chat-default-behavior db)) config)
         past-messages (get-in db [:chats chat-id :messages] [])
         all-tools (f.tools/all-tools @db* config)
         received-msgs* (atom "")
@@ -210,12 +210,14 @@
       :on-tool-called (fn [{:keys [id name arguments] :as tool-call}]
                         (assert-chat-not-stopped! chat-ctx)
                         (send-content! chat-ctx :assistant
-                                       {:type :toolCallRun
-                                        :name name
-                                        :origin (tool-name->origin name all-tools)
-                                        :arguments arguments
-                                        :id id
-                                        :manual-approval manual-approval?})
+                                       (assoc-some
+                                        {:type :toolCallRun
+                                         :name name
+                                         :origin (tool-name->origin name all-tools)
+                                         :arguments arguments
+                                         :id id
+                                         :manual-approval manual-approval?}
+                                        :details (f.tools/get-tool-call-details name arguments)))
                         (let [approved?* (promise)]
                           (swap! db* assoc-in [:chats chat-id :tool-calls id :approved?*] approved?*)
                           (when-not (string/blank? @received-msgs*)

src/eca/features/prompt.clj

@@ -8,8 +8,9 @@
 
 (def ^:private eca-prompt-template (memoize eca-prompt-template*))
 
-(defn ^:private eca-prompt [behavior]
-  (let [prompt (eca-prompt-template)]
+(defn ^:private eca-prompt [behavior config]
+  (let [prompt (or (:systemPromptTemplate config)
+                   (eca-prompt-template))]
     (reduce
      (fn [p [k v]]
        (string/replace p (str "{" (name k) "}") v))
@@ -18,9 +19,9 @@
                   "chat" "Answer questions, and provide explanations."
                   "agent" "You are an agent - please keep going until the user's query is completely resolved, before ending your turn and yielding back to the user. Only terminate your turn when you are sure that the problem is solved. Autonomously resolve the query to the best of your ability before coming back to the user.")})))
 
-(defn build-instructions [refined-contexts rules repo-map* behavior]
+(defn build-instructions [refined-contexts rules repo-map* behavior config]
   (multi-str
-   (eca-prompt behavior)
+   (eca-prompt behavior config)
    "<rules>"
    (reduce
     (fn [rule-str {:keys [name content]}]

src/eca/features/tools.clj

@@ -3,6 +3,7 @@
    eca native tools and MCP servers."
   (:require
    [clojure.string :as string]
+   [eca.diff :as diff]
    [eca.features.tools.filesystem :as f.tools.filesystem]
    [eca.features.tools.mcp :as f.mcp]
    [eca.features.tools.shell :as f.tools.shell]
@@ -95,3 +96,19 @@
                            (messenger/tool-server-updated messenger (-> server
                                                                         (assoc :type :mcp)
                                                                         (update :tools #(mapv with-tool-status %)))))})))
+(defn get-tool-call-details [name arguments]
+  (case name
+    "eca_edit_file" (let [path (get arguments "path")
+                          original-content (get arguments "original_content")
+                          new-content (get arguments "new_content")
+                          all? (get arguments "all_occurrences")]
+                      (when-let [{:keys [original-full-content
+                                         new-full-content]} (and path original-content new-content
+                                                                 (f.tools.filesystem/file-change-full-content path original-content new-content all?))]
+                        (let [{:keys [added removed diff]} (diff/diff original-full-content new-full-content path)]
+                          {:type :fileChange
+                           :path path
+                           :linesAdded added
+                           :linesRemoved removed
+                           :diff diff})))
+    nil))

src/eca/features/tools/filesystem.clj

@@ -146,19 +146,25 @@
           (tools.util/single-text-content (string/join "\n" paths))
           (tools.util/single-text-content "No files found for given pattern" :error)))))
 
+(defn file-change-full-content [path original-content new-content all?]
+  (let [original-full-content (slurp path)
+        new-full-content (if all?
+                           (string/replace original-full-content original-content new-content)
+                           (string/replace-first original-full-content original-content new-content))]
+    (when (string/includes? original-full-content original-content)
+      {:original-full-content original-full-content
+       :new-full-content new-full-content})))
+
 (defn ^:private edit-file [arguments {:keys [db]}]
   (or (tools.util/invalid-arguments arguments (concat (path-validations db)
                                                       [["path" fs/readable? "File $path is not readable"]]))
       (let [path (get arguments "path")
             original-content (get arguments "original_content")
             new-content (get arguments "new_content")
-            all? (boolean (get arguments "all_occurrences"))
-            content (slurp path)]
-        (if (string/includes? content original-content)
-          (let [content (if all?
-                          (string/replace content original-content new-content)
-                          (string/replace-first content original-content new-content))]
-            (spit path content)
+            all? (boolean (get arguments "all_occurrences"))]
+        (if-let [{:keys [new-full-content]} (file-change-full-content path original-content new-content all?)]
+          (do
+            (spit path new-full-content)
             (tools.util/single-text-content (format "Successfully replaced content in %s." path)))
           (tools.util/single-text-content (format "Original content not found in %s" path) :error)))))