Keep executed tool steps when a generation fails

CHANGELOG.md

@@ -4,6 +4,13 @@
 
 ### Changes
 
+- [Provider] Work a tool already did is no longer redone when the turn it was part of breaks partway
+  through. A model turn can run several tool calls before it fails — because the model asked for a
+  tool that does not exist, answered in plain text where a tool call was demanded, or ran the
+  conversation past the model's context limit. The whole turn was then retried from its starting
+  point, with no trace that the earlier calls had already gone through, so everything they had
+  created got created again, once per retry. The calls that completed now carry over into the retry
+  and into the conversation, and the model continues from them instead of repeating them.
 - Doc Collector: a `docs collect` run streamed with `--ws` now sends the spec index it generates as a
   `docs` frame — the file path and the full markdown of `docs/index.md` — so a listening UI can show
   the finished documentation the same way an exploration run streams its session report.

src/ai/provider.ts

@@ -426,10 +426,20 @@ export class Provider {
     const config = this.buildGenerateConfig({ tools: toolsWithCommentary, maxOutputTokens: 16384, toolChoice: 'auto', experimental_repairToolCall: repairToolCall }, { stopWhen: stopConditions, model }, options);
     let attemptMessages = messages;
     let invalidRequestFeedbackAdded = false;
+    const executedStepMessages: ModelMessage[] = [];
     try {
       const response = await this.withModelRequestSlot(() =>
         withRetry(async () => {
-          const result = (await this.raceWithIdleTimeout((signal) => generateText({ messages: attemptMessages, ...config, abortSignal: signal }), config.timeout || 30000).catch((error) => {
+          const stepMessages: ModelMessage[] = [];
+          const onStepEnd = (step: any) => {
+            stepMessages.push(...(step.response?.messages || []));
+          };
+          const result = (await this.raceWithIdleTimeout((signal) => generateText({ messages: attemptMessages, ...config, abortSignal: signal, onStepEnd }), config.timeout || 30000).catch((error) => {
+            if (stepMessages.length > 0) {
+              tag('warning').log(`Keeping ${stepMessages.length} messages from tool steps that already ran before the failure`);
+              executedStepMessages.push(...stepMessages);
+              attemptMessages = [...attemptMessages, ...stepMessages];
+            }
             if (!invalidRequestFeedbackAdded) {
               const amended = withInvalidRequestFeedback(attemptMessages, error);
               invalidRequestFeedbackAdded = amended !== attemptMessages;
@@ -448,6 +458,8 @@ export class Provider {
 
       clearActivity();
 
+      withExecutedSteps(response, executedStepMessages);
+
       // Log tool usage summary
       if (response.toolCalls && response.toolCalls.length > 0) {
         responseLog(response.toolCalls);
@@ -462,12 +474,13 @@ export class Provider {
     } catch (error: any) {
       clearActivity();
       if (error?.message?.includes('Tool choice is required')) {
-        return { text: '', toolCalls: [], toolResults: [], response: { messages: [] }, usage: null };
+        return { text: '', toolCalls: [], toolResults: [], responseMessages: executedStepMessages, usage: null };
       }
       if (error?.name === 'AbortError') throw error;
       if (error instanceof ContextLengthError) throw error;
       if (Provider.isContextLengthError(error)) {
-        return this.recoverFromContextLength(error, messages, options, (m, o) => this.generateWithTools(m, model, tools, o));
+        const recovered = await this.recoverFromContextLength(error, attemptMessages, options, (m, o) => this.generateWithTools(m, model, tools, o));
+        return withExecutedSteps(recovered, executedStepMessages);
       }
       if (error.constructor?.name === 'AI_APICallError') {
         responseLog(error.message);
@@ -703,6 +716,11 @@ function repairToolCall(options: ToolCallRepairOptions): any | null {
   return repairHarmonyChannel(options);
 }
 
+function withExecutedSteps(result: any, executed: ModelMessage[]): any {
+  if (executed.length === 0) return result;
+  return Object.defineProperty(result, 'responseMessages', { value: [...executed, ...(result.responseMessages || [])], configurable: true, enumerable: true });
+}
+
 function withInvalidRequestFeedback(messages: ModelMessage[], error: unknown): ModelMessage[] {
   if (!(error instanceof APICallError) || error.statusCode !== 400) return messages;
   tag('warning').log('Provider rejected the request as invalid — relaying its reason before the retry');

tests/unit/provider.test.ts

@@ -348,6 +348,93 @@ describe('Provider', () => {
       expect(JSON.stringify(relayed.content)).toContain('attempted to call a tool which was not in request.tools');
     });
 
+    it('carries tool steps that already ran into the retry', async () => {
+      const prompts: any[] = [];
+      let calls = 0;
+      let created = 0;
+      const model = new MockLanguageModelV3({
+        provider: 'test',
+        modelId: 'test',
+        doGenerate: async (params: any) => {
+          calls++;
+          prompts.push(params.prompt);
+          if (calls === 1) {
+            return {
+              text: undefined,
+              toolCalls: [{ toolCallId: 'c1', toolName: 'create', args: { name: 'suite' } }],
+              finishReason: 'tool-calls' as const,
+              usage: { inputTokens: 1, outputTokens: 1 },
+              content: [{ type: 'tool-call' as const, toolCallId: 'c1', toolName: 'create', input: JSON.stringify({ name: 'suite' }) }],
+            };
+          }
+          if (calls === 2) {
+            throw new APICallError({ url: 'http://test.local/v1/chat', statusCode: 400, message: 'Tool call validation failed: attempted to call a tool which was not in request.tools' });
+          }
+          return { text: 'done', finishReason: 'stop', usage: { inputTokens: 1, outputTokens: 1 }, content: [{ type: 'text' as const, text: 'done' }] };
+        },
+      });
+      aiConfig.retryDelay = 1;
+      const retryingProvider = new Provider(aiConfig);
+      const tools = {
+        create: tool({
+          description: 'Create a record',
+          inputSchema: z.object({ name: z.string() }),
+          execute: async () => {
+            created++;
+            return { id: 1 };
+          },
+        }),
+      };
+
+      const response = await retryingProvider.generateWithTools([{ role: 'user', content: 'go' }], model, tools, { maxRetries: 3 });
+
+      expect(created).toBe(1);
+      expect(JSON.stringify(prompts[2])).toContain('c1');
+      expect(response.responseMessages.filter((m: any) => m.role === 'tool')).toHaveLength(1);
+      expect(response.responseMessages.at(-1).content).toEqual([{ type: 'text', text: 'done' }]);
+    });
+
+    it('returns the tool steps that ran when the provider rejects every retry', async () => {
+      let calls = 0;
+      let created = 0;
+      const model = new MockLanguageModelV3({
+        provider: 'test',
+        modelId: 'test',
+        doGenerate: async () => {
+          calls++;
+          if (calls === 1) {
+            return {
+              text: undefined,
+              toolCalls: [{ toolCallId: 'c1', toolName: 'create', args: { name: 'suite' } }],
+              finishReason: 'tool-calls' as const,
+              usage: { inputTokens: 1, outputTokens: 1 },
+              content: [{ type: 'tool-call' as const, toolCallId: 'c1', toolName: 'create', input: JSON.stringify({ name: 'suite' }) }],
+            };
+          }
+          throw new APICallError({ url: 'http://test.local/v1/chat', statusCode: 400, message: 'Tool choice is required, but model did not call a tool' });
+        },
+      });
+      aiConfig.retryDelay = 1;
+      const retryingProvider = new Provider(aiConfig);
+      const tools = {
+        create: tool({
+          description: 'Create a record',
+          inputSchema: z.object({ name: z.string() }),
+          execute: async () => {
+            created++;
+            return { id: 1 };
+          },
+        }),
+      };
+
+      const response = await retryingProvider.generateWithTools([{ role: 'user', content: 'go' }], model, tools, { maxRetries: 2 });
+
+      expect(created).toBe(1);
+      expect(response.text).toBe('');
+      expect(response.responseMessages).toHaveLength(2);
+      expect(response.responseMessages[1].role).toBe('tool');
+    });
+
     it('should honor configured retry attempts and delay', () => {
       aiConfig.retryAttempts = 7;
       aiConfig.retryDelay = 250;
@@ -659,6 +746,49 @@ describe('Provider', () => {
       expect(response.text).toBe('recovered');
       expect(calls).toBe(2);
     });
+
+    it('keeps tool steps that already ran when it reduces messages', async () => {
+      const prompts: any[] = [];
+      let calls = 0;
+      let created = 0;
+      const model = new MockLanguageModelV3({
+        provider: 'test',
+        modelId: 'ctx-tools-model',
+        doGenerate: async (params: any) => {
+          calls++;
+          prompts.push(params.prompt);
+          if (calls === 1) {
+            return {
+              text: undefined,
+              toolCalls: [{ toolCallId: 'c1', toolName: 'create', args: { name: 'suite' } }],
+              finishReason: 'tool-calls' as const,
+              usage: { inputTokens: 1, outputTokens: 1 },
+              content: [{ type: 'tool-call' as const, toolCallId: 'c1', toolName: 'create', input: JSON.stringify({ name: 'suite' }) }],
+            };
+          }
+          if (calls === 2) throw new Error('context length exceeded');
+          return { text: 'recovered', finishReason: 'stop' as const, usage: { inputTokens: 1, outputTokens: 1 }, content: [{ type: 'text' as const, text: 'recovered' }] };
+        },
+      });
+      const tools = {
+        create: tool({
+          description: 'Create a record',
+          inputSchema: z.object({ name: z.string() }),
+          execute: async () => {
+            created++;
+            return { id: 1 };
+          },
+        }),
+      };
+      const messages: ModelMessage[] = [{ role: 'user', content: `<data>${'x'.repeat(5000)}</data>` }];
+
+      const response = await provider.generateWithTools(messages, model, tools, { maxRetries: 1 });
+
+      expect(created).toBe(1);
+      expect(response.text).toBe('recovered');
+      expect(JSON.stringify(prompts[2])).toContain('c1');
+      expect(response.responseMessages.filter((m: any) => m.role === 'tool')).toHaveLength(1);
+    });
   });
 
   describe('abort on idle timeout', () => {