Extract shared toJsonSchemaObject helper for JSON Schema conversion

Both ClaudeTextGeneration and CodexTextGeneration had identical logic
to convert an Effect Schema into a flat JSON Schema object. Move it
into textGenerationUtils.ts as a single shared helper.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: keyzou

apps/server/src/git/Layers/ClaudeTextGeneration.ts

@@ -26,21 +26,11 @@ import {
   buildCommitMessagePrompt,
   buildPrContentPrompt,
 } from "./textGenerationPrompts.ts";
-import { normalizeCliError, sanitizeCommitSubject, sanitizePrTitle } from "./textGenerationUtils.ts";
+import { normalizeCliError, sanitizeCommitSubject, sanitizePrTitle, toJsonSchemaObject } from "./textGenerationUtils.ts";
 
 const CLAUDE_REASONING_EFFORT = "low";
 const CLAUDE_TIMEOUT_MS = 180_000;
 
-/** Build a JSON-schema string suitable for the Claude CLI `--json-schema` flag. */
-function toClaudeJsonSchemaString(schema: Schema.Top): string {
-  const document = Schema.toJsonSchemaDocument(schema);
-  const schemaObj =
-    document.definitions && Object.keys(document.definitions).length > 0
-      ? { ...document.schema, $defs: document.definitions }
-      : document.schema;
-  return JSON.stringify(schemaObj);
-}
-
 /**
  * Schema for the wrapper JSON returned by `claude -p --output-format json`.
  * We only care about `structured_output`.
@@ -88,7 +78,7 @@ const makeClaudeTextGeneration = Effect.gen(function* () {
     model?: string;
   }): Effect.Effect<S["Type"], TextGenerationError, S["DecodingServices"]> =>
     Effect.gen(function* () {
-      const jsonSchemaStr = toClaudeJsonSchemaString(outputSchemaJson);
+      const jsonSchemaStr = JSON.stringify(toJsonSchemaObject(outputSchemaJson));
 
       const runClaudeCommand = Effect.gen(function* () {
         const command = ChildProcess.make(

apps/server/src/git/Layers/CodexTextGeneration.ts

@@ -22,22 +22,11 @@ import {
   buildCommitMessagePrompt,
   buildPrContentPrompt,
 } from "./textGenerationPrompts.ts";
-import { normalizeCliError, sanitizeCommitSubject, sanitizePrTitle } from "./textGenerationUtils.ts";
+import { normalizeCliError, sanitizeCommitSubject, sanitizePrTitle, toJsonSchemaObject } from "./textGenerationUtils.ts";
 
 const CODEX_REASONING_EFFORT = "low";
 const CODEX_TIMEOUT_MS = 180_000;
 
-function toCodexOutputJsonSchema(schema: Schema.Top): unknown {
-  const document = Schema.toJsonSchemaDocument(schema);
-  if (document.definitions && Object.keys(document.definitions).length > 0) {
-    return {
-      ...document.schema,
-      $defs: document.definitions,
-    };
-  }
-  return document.schema;
-}
-
 const makeCodexTextGeneration = Effect.gen(function* () {
   const fileSystem = yield* FileSystem.FileSystem;
   const path = yield* Path.Path;
@@ -144,7 +133,7 @@ const makeCodexTextGeneration = Effect.gen(function* () {
       const schemaPath = yield* writeTempFile(
         operation,
         "codex-schema",
-        JSON.stringify(toCodexOutputJsonSchema(outputSchemaJson)),
+        JSON.stringify(toJsonSchemaObject(outputSchemaJson)),
       );
       const outputPath = yield* writeTempFile(operation, "codex-output", "");
 

apps/server/src/git/Layers/textGenerationUtils.ts

@@ -7,6 +7,15 @@ import { Schema } from "effect";
 
 import { TextGenerationError } from "../Errors.ts";
 
+/** Convert an Effect Schema to a flat JSON Schema object, inlining `$defs` when present. */
+export function toJsonSchemaObject(schema: Schema.Top): unknown {
+  const document = Schema.toJsonSchemaDocument(schema);
+  if (document.definitions && Object.keys(document.definitions).length > 0) {
+    return { ...document.schema, $defs: document.definitions };
+  }
+  return document.schema;
+}
+
 /** Truncate a text section to `maxChars`, appending a `[truncated]` marker when needed. */
 export function limitSection(value: string, maxChars: number): string {
   if (value.length <= maxChars) return value;