peter-daptic · Oct 29, 2026
diff --git a/.changeset/openai-streamed-apply-patch-diff.md b/.changeset/openai-streamed-apply-patch-diff.md
@@ -0,0 +1,5 @@
+---
+'@tanstack/openai-base': patch
+---
+
+Pass the full diff of a streamed `apply_patch` call to the app. The Responses API adds an `apply_patch_call` with `status: "in_progress"` and an empty `diff`, and streams the diff in before the item is done. The adapter ended the call when the item was added, so `execute` always got `diff: ""`, and an agent loop sent empty patches until it hit its iteration limit. A user-run call (`apply_patch`, `local_shell`, `shell`, `computer`) now starts when its item is added and ends, with its input, once the item is no longer in progress, as function calls already do.
diff --git a/packages/openai-base/src/adapters/responses-text.ts b/packages/openai-base/src/adapters/responses-text.ts
@@ -1595,6 +1595,14 @@ export abstract class OpenAIBaseResponsesTextAdapter<
       return tracked
     }
 
+    /**
+     * The tool call chunks for a user-run item (`apply_patch_call`,
+     * `shell_call`, `local_shell_call`, `computer_call`). The first time a call
+     * is seen it emits `TOOL_CALL_START`. While the item is `in_progress` its
+     * input may be incomplete (an `apply_patch_call` has an empty diff), so
+     * `TOOL_CALL_END` waits until the item has any other status, and then
+     * carries the complete input. An ended call emits nothing.
+     */
     const userToolChunks = (
       item: unknown,
       outputIndex: number,
@@ -1609,21 +1617,21 @@ export abstract class OpenAIBaseResponsesTextAdapter<
         started: false,
       }
       toolCallMetadata.set(call.callId, tracked)
-      tracked.started = true
-      tracked.ended = true
       tracked.name = call.name
       streamedToolCall = true
       const timestamp = Date.now()
       const modelName = model || options.model
-      const metadata: OpenAIResponsesToolCallMetadata = {
-        openaiUserTool: call.name,
-        ...(call.itemId ? { itemId: call.itemId } : {}),
-        ...(call.maxOutputLength !== undefined
-          ? { maxOutputLength: call.maxOutputLength }
-          : {}),
-      }
-      return [
-        {
+      const chunks: Array<AdapterYieldChunk> = []
+      if (!tracked.started) {
+        tracked.started = true
+        const metadata: OpenAIResponsesToolCallMetadata = {
+          openaiUserTool: call.name,
+          ...(call.itemId ? { itemId: call.itemId } : {}),
+          ...(call.maxOutputLength !== undefined
+            ? { maxOutputLength: call.maxOutputLength }
+            : {}),
+        }
+        chunks.push({
           type: EventType.TOOL_CALL_START,
           toolCallId: call.callId,
           toolCallName: call.name,
@@ -1632,16 +1640,19 @@ export abstract class OpenAIBaseResponsesTextAdapter<
           timestamp,
           index: outputIndex,
           metadata,
-        },
-        {
-          type: EventType.TOOL_CALL_END,
-          toolCallId: call.callId,
-          toolCallName: call.name,
-          model: modelName,
-          timestamp,
-          input: call.input,
-        },
-      ]
+        })
+      }
+      if (isRecord(item) && item.status === 'in_progress') return chunks
+      tracked.ended = true
+      chunks.push({
+        type: EventType.TOOL_CALL_END,
+        toolCallId: call.callId,
+        toolCallName: call.name,
+        model: modelName,
+        timestamp,
+        input: call.input,
+      })
+      return chunks
     }
 
     const emitReasoningDelta = function* (

diff --git a/packages/openai-base/tests/responses-text.test.ts b/packages/openai-base/tests/responses-text.test.ts
@@ -4765,6 +4765,81 @@ describe('OpenAIBaseResponsesTextAdapter', () => {
       expect(finished).toMatchObject({ finishReason: 'tool_calls' })
     })
 
+    it('passes the streamed diff of an apply_patch_call to the app', async () => {
+      // The diff is empty when the item is added and streams in afterwards.
+      const diff = '@@\n-def fib\n+def fibonacci\n'
+      const item = (status: string, itemDiff: string) => ({
+        type: 'apply_patch_call',
+        id: 'apc_1',
+        call_id: 'call_patch',
+        status,
+        operation: { type: 'update_file', path: 'lib/fib.py', diff: itemDiff },
+      })
+      setupMockResponsesClient([
+        {
+          type: 'response.created',
+          response: {
+            id: 'resp-user-tool',
+            model: 'test-model',
+            status: 'in_progress',
+          },
+        },
+        {
+          type: 'response.output_item.added',
+          output_index: 0,
+          item: item('in_progress', ''),
+        },
+        {
+          type: 'response.apply_patch_call_operation_diff.delta',
+          output_index: 0,
+          item_id: 'apc_1',
+          delta: diff,
+        },
+        {
+          type: 'response.apply_patch_call_operation_diff.done',
+          output_index: 0,
+          item_id: 'apc_1',
+        },
+        {
+          type: 'response.output_item.done',
+          output_index: 0,
+          item: item('completed', diff),
+        },
+        {
+          type: 'response.completed',
+          response: {
+            id: 'resp-user-tool',
+            model: 'test-model',
+            status: 'completed',
+            output: [item('completed', diff)],
+            usage: { input_tokens: 1, output_tokens: 1, total_tokens: 2 },
+          },
+        },
+      ])
+      const adapter = new TestResponsesAdapter(testConfig, 'test-model')
+      const chunks: Array<AdapterYieldChunk> = []
+      for await (const chunk of adapter.chatStream({
+        threadId: 'thread-1',
+        logger: testLogger,
+        model: 'test-model',
+        messages: [{ role: 'user', content: 'edit the file' }],
+        tools: [applyPatchTool()],
+      })) {
+        chunks.push(chunk)
+      }
+
+      const starts = chunks.filter((chunk) => chunk.type === 'TOOL_CALL_START')
+      const ends = chunks.filter((chunk) => chunk.type === 'TOOL_CALL_END')
+      expect(starts).toHaveLength(1)
+      expect(ends).toHaveLength(1)
+      expect(ends[0]).toMatchObject({
+        toolCallId: 'call_patch',
+        input: {
+          operation: { type: 'update_file', path: 'lib/fib.py', diff },
+        },
+      })
+    })
+
     it('surfaces a local shell call and ignores a hosted container shell', async () => {
       const chunks = await collect([
         {

diff --git a/testing/e2e/src/routeTree.gen.ts b/testing/e2e/src/routeTree.gen.ts
@@ -150,6 +150,7 @@ import { Route as ApiMoonshotUsageDetailsRouteImport } from './routes/api.moonsh
 import { Route as ApiMultimodalToolResultWireRouteImport } from './routes/api.multimodal-tool-result-wire'
 import { Route as ApiNeonWireRouteImport } from './routes/api.neon-wire'
 import { Route as ApiNonStreamingRunErrorRouteImport } from './routes/api.non-streaming-run-error'
+import { Route as ApiOpenaiApplyPatchWireRouteImport } from './routes/api.openai-apply-patch-wire'
 import { Route as ApiOpenaiCompletedResponseTextRouteImport } from './routes/api.openai-completed-response-text'
 import { Route as ApiOpenaiComputerUseWireRouteImport } from './routes/api.openai-computer-use-wire'
 import { Route as ApiOpenaiImage25ModelsRouteImport } from './routes/api.openai-image-2-5-models'
@@ -945,6 +946,11 @@ const ApiNonStreamingRunErrorRoute = ApiNonStreamingRunErrorRouteImport.update({
   path: '/api/non-streaming-run-error',
   getParentRoute: () => rootRouteImport,
 } as any)
+const ApiOpenaiApplyPatchWireRoute = ApiOpenaiApplyPatchWireRouteImport.update({
+  id: '/api/openai-apply-patch-wire',
+  path: '/api/openai-apply-patch-wire',
+  getParentRoute: () => rootRouteImport,
+} as any)
 const ApiOpenaiCompletedResponseTextRoute =
   ApiOpenaiCompletedResponseTextRouteImport.update({
     id: '/api/openai-completed-response-text',
@@ -1408,6 +1414,7 @@ export interface FileRoutesByFullPath {
   '/api/multimodal-tool-result-wire': typeof ApiMultimodalToolResultWireRoute
   '/api/neon-wire': typeof ApiNeonWireRoute
   '/api/non-streaming-run-error': typeof ApiNonStreamingRunErrorRoute
+  '/api/openai-apply-patch-wire': typeof ApiOpenaiApplyPatchWireRoute
   '/api/openai-completed-response-text': typeof ApiOpenaiCompletedResponseTextRoute
   '/api/openai-computer-use-wire': typeof ApiOpenaiComputerUseWireRoute
   '/api/openai-image-2-5-models': typeof ApiOpenaiImage25ModelsRoute
@@ -1611,6 +1618,7 @@ export interface FileRoutesByTo {
   '/api/multimodal-tool-result-wire': typeof ApiMultimodalToolResultWireRoute
   '/api/neon-wire': typeof ApiNeonWireRoute
   '/api/non-streaming-run-error': typeof ApiNonStreamingRunErrorRoute
+  '/api/openai-apply-patch-wire': typeof ApiOpenaiApplyPatchWireRoute
   '/api/openai-completed-response-text': typeof ApiOpenaiCompletedResponseTextRoute
   '/api/openai-computer-use-wire': typeof ApiOpenaiComputerUseWireRoute
   '/api/openai-image-2-5-models': typeof ApiOpenaiImage25ModelsRoute
@@ -1815,6 +1823,7 @@ export interface FileRoutesById {
   '/api/multimodal-tool-result-wire': typeof ApiMultimodalToolResultWireRoute
   '/api/neon-wire': typeof ApiNeonWireRoute
   '/api/non-streaming-run-error': typeof ApiNonStreamingRunErrorRoute
+  '/api/openai-apply-patch-wire': typeof ApiOpenaiApplyPatchWireRoute
   '/api/openai-completed-response-text': typeof ApiOpenaiCompletedResponseTextRoute
   '/api/openai-computer-use-wire': typeof ApiOpenaiComputerUseWireRoute
   '/api/openai-image-2-5-models': typeof ApiOpenaiImage25ModelsRoute
@@ -2020,6 +2029,7 @@ export interface FileRouteTypes {
     | '/api/multimodal-tool-result-wire'
     | '/api/neon-wire'
     | '/api/non-streaming-run-error'
+    | '/api/openai-apply-patch-wire'
     | '/api/openai-completed-response-text'
     | '/api/openai-computer-use-wire'
     | '/api/openai-image-2-5-models'
@@ -2223,6 +2233,7 @@ export interface FileRouteTypes {
     | '/api/multimodal-tool-result-wire'
     | '/api/neon-wire'
     | '/api/non-streaming-run-error'
+    | '/api/openai-apply-patch-wire'
     | '/api/openai-completed-response-text'
     | '/api/openai-computer-use-wire'
     | '/api/openai-image-2-5-models'
@@ -2426,6 +2437,7 @@ export interface FileRouteTypes {
     | '/api/multimodal-tool-result-wire'
     | '/api/neon-wire'
     | '/api/non-streaming-run-error'
+    | '/api/openai-apply-patch-wire'
     | '/api/openai-completed-response-text'
     | '/api/openai-computer-use-wire'
     | '/api/openai-image-2-5-models'
@@ -2630,6 +2642,7 @@ export interface RootRouteChildren {
   ApiMultimodalToolResultWireRoute: typeof ApiMultimodalToolResultWireRoute
   ApiNeonWireRoute: typeof ApiNeonWireRoute
   ApiNonStreamingRunErrorRoute: typeof ApiNonStreamingRunErrorRoute
+  ApiOpenaiApplyPatchWireRoute: typeof ApiOpenaiApplyPatchWireRoute
   ApiOpenaiCompletedResponseTextRoute: typeof ApiOpenaiCompletedResponseTextRoute
   ApiOpenaiComputerUseWireRoute: typeof ApiOpenaiComputerUseWireRoute
   ApiOpenaiImage25ModelsRoute: typeof ApiOpenaiImage25ModelsRoute
@@ -3677,6 +3690,13 @@ declare module '@tanstack/react-router' {
       preLoaderRoute: typeof ApiNonStreamingRunErrorRouteImport
       parentRoute: typeof rootRouteImport
     }
+    '/api/openai-apply-patch-wire': {
+      id: '/api/openai-apply-patch-wire'
+      path: '/api/openai-apply-patch-wire'
+      fullPath: '/api/openai-apply-patch-wire'
+      preLoaderRoute: typeof ApiOpenaiApplyPatchWireRouteImport
+      parentRoute: typeof rootRouteImport
+    }
     '/api/openai-completed-response-text': {
       id: '/api/openai-completed-response-text'
       path: '/api/openai-completed-response-text'
@@ -4304,6 +4324,7 @@ const rootRouteChildren: RootRouteChildren = {
   ApiMultimodalToolResultWireRoute: ApiMultimodalToolResultWireRoute,
   ApiNeonWireRoute: ApiNeonWireRoute,
   ApiNonStreamingRunErrorRoute: ApiNonStreamingRunErrorRoute,
+  ApiOpenaiApplyPatchWireRoute: ApiOpenaiApplyPatchWireRoute,
   ApiOpenaiCompletedResponseTextRoute: ApiOpenaiCompletedResponseTextRoute,
   ApiOpenaiComputerUseWireRoute: ApiOpenaiComputerUseWireRoute,
   ApiOpenaiImage25ModelsRoute: ApiOpenaiImage25ModelsRoute,