feat: allow file_edit_insert to create files implicitly

Author: ammar-agent

src/services/tools/file_edit_insert.test.ts

@@ -96,20 +96,33 @@ describe("file_edit_insert tool", () => {
     }
   });
 
-  it("creates new file when create flag is provided", async () => {
+  it("creates a new file without requiring create flag or guards", async () => {
     const newFile = path.join(testDir, "new.txt");
     const tool = createTestTool(testDir);
     const args: FileEditInsertToolArgs = {
       file_path: path.relative(testDir, newFile),
       content: "Hello world!\n",
-      create: true,
     };
 
     const result = (await tool.execute!(args, mockToolCallOptions)) as FileEditInsertToolResult;
     expect(result.success).toBe(true);
     expect(await fs.readFile(newFile, "utf-8")).toBe("Hello world!\n");
   });
 
+  it("still supports the legacy create flag for backwards compatibility", async () => {
+    const newFile = path.join(testDir, "legacy.txt");
+    const tool = createTestTool(testDir);
+    const args: FileEditInsertToolArgs = {
+      file_path: path.relative(testDir, newFile),
+      content: "Legacy\n",
+      create: true,
+    };
+
+    const result = (await tool.execute!(args, mockToolCallOptions)) as FileEditInsertToolResult;
+    expect(result.success).toBe(true);
+    expect(await fs.readFile(newFile, "utf-8")).toBe("Legacy\n");
+  });
+
   it("fails when no guards are provided", async () => {
     const tool = createTestTool(testDir);
     const args: FileEditInsertToolArgs = {

src/services/tools/file_edit_insert.ts

@@ -48,7 +48,7 @@ export const createFileEditInsertTool: ToolFactory = (config: ToolConfiguration)
     description: TOOL_DEFINITIONS.file_edit_insert.description,
     inputSchema: TOOL_DEFINITIONS.file_edit_insert.schema,
     execute: async (
-      { file_path, content, before, after, create }: FileEditInsertToolArgs,
+      { file_path, content, before, after }: FileEditInsertToolArgs,
       { abortSignal }
     ): Promise<FileEditInsertToolResult> => {
       try {
@@ -71,14 +71,6 @@ export const createFileEditInsertTool: ToolFactory = (config: ToolConfiguration)
         const exists = await fileExists(config.runtime, resolvedPath, abortSignal);
 
         if (!exists) {
-          if (!create) {
-            return {
-              success: false,
-              error: `File not found: ${file_path}. Set create: true to create it.`,
-              note: `${EDIT_FAILED_NOTE_PREFIX} File does not exist. Set create: true to create it, or check the file path.`,
-            };
-          }
-
           try {
             await writeFileString(config.runtime, resolvedPath, content, abortSignal);
           } catch (err) {
@@ -139,7 +131,7 @@ function insertContent(
   }
 
   if (before === undefined && after === undefined) {
-    return guardFailure("Provide either a before or after guard to anchor the insertion point.");
+    return guardFailure("Provide either a before or after guard when editing existing files.");
   }
 
   return insertWithGuards(originalContent, contentToInsert, { before, after });

src/types/tools.ts

@@ -74,7 +74,7 @@ export interface FileEditErrorResult {
 export interface FileEditInsertToolArgs {
   file_path: string;
   content: string;
-  /** When true, create the file if it doesn't exist */
+  /** @deprecated Legacy no-op. Files are created automatically when missing. */
   create?: boolean;
   /** Optional substring that must appear immediately before the insertion point */
   before?: string;

src/utils/tools/toolDefinitions.ts

@@ -116,13 +116,16 @@ export const TOOL_DEFINITIONS = {
     description:
       "Insert content into a file using substring guards. " +
       "Provide exactly one of before or after to anchor the operation when editing an existing file. " +
-      "Set create: true to write a brand new file without guards. " +
+      "Missing files are created automatically, so guards are optional when creating new files. " +
       `Optional before/after substrings must uniquely match surrounding content. ${TOOL_EDIT_WARNING}`,
     schema: z
       .object({
         file_path: FILE_EDIT_FILE_PATH,
         content: z.string().describe("The content to insert"),
-        create: z.boolean().optional().describe("If true, create the file if it does not exist"),
+        create: z
+          .boolean()
+          .optional()
+          .describe("Legacy compatibility; files are created automatically when missing, so this flag is ignored."),
         before: z
           .string()
           .min(1)
@@ -134,14 +137,6 @@ export const TOOL_DEFINITIONS = {
           .optional()
           .describe("Optional substring that must appear immediately after the insertion point"),
       })
-      .refine(
-        (data) => data.create === true || data.before !== undefined || data.after !== undefined,
-        {
-          message:
-            "Provide before or after when editing existing files, or set create: true to write a new file.",
-          path: ["before"],
-        }
-      )
       .refine((data) => !(data.before !== undefined && data.after !== undefined), {
         message: "Provide only one of before or after (not both).",
         path: ["before"],