fix(server): transcript key & bump models (#15485)

#### PR Dependency Tree


* **PR #15485** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **New Features**
* Upgraded built-in AI actions and chat model selection to Gemini 3.7
Flash.
* Transcript attachments now retain storage keys and support secure
presigned URLs during processing.
* Completed transcript results preserve attachment metadata for reliable
access.

* **Bug Fixes**
* Improved transcript handling across uploads, retries, and native
processing.
  * Added safeguards for invalid or missing attachment URLs.

* **Maintenance**
* Added a migration to backfill storage keys for existing transcript
records without altering their URLs.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/backend/server/src/__tests__/copilot/transcript-contract.spec.ts

@@ -294,7 +294,7 @@ test('retryTask reuses failed task and queues a new action attempt', async t =>
     } as never,
     {} as never,
     {
-      resolveTranscriptionModel: Sinon.stub().resolves('gemini-3.5-flash-lite'),
+      resolveTranscriptionModel: Sinon.stub().resolves('gemini-3.7-flash'),
     } as never,
     {} as never,
     {} as never,
@@ -303,7 +303,7 @@ test('retryTask reuses failed task and queues a new action attempt', async t =>
 
   const result = await service.retryTask('user-1', 'workspace-1', 'task-1');
 
-  t.is(result.status, AiJobStatus.running);
+  t.is(result?.status, AiJobStatus.running);
   t.like(queuedJobs[0] as Record<string, unknown>, {
     name: 'copilot.transcript.task.submit',
   });
@@ -351,9 +351,7 @@ for (const status of ['ready', 'settled']) {
       } as never,
       {} as never,
       {
-        resolveTranscriptionModel: Sinon.stub().resolves(
-          'gemini-3.5-flash-lite'
-        ),
+        resolveTranscriptionModel: Sinon.stub().resolves('gemini-3.7-flash'),
       } as never,
       {} as never,
       {} as never,
@@ -403,7 +401,8 @@ test('transcriptTask runs native transcript recipe through action bridge when av
     ],
     infos: [
       {
-        url: 'data:image/png;base64,YXVkaW8=',
+        key: 'blob-1-0',
+        url: 'https://affine.fail/api/copilot/blob/user-1/workspace-1/blob-1-0',
         mimeType: 'audio/opus',
         index: 0,
       },
@@ -428,7 +427,11 @@ test('transcriptTask runs native transcript recipe through action bridge when av
       },
     } as never,
     {} as never,
-    {} as never,
+    {
+      presignGet: Sinon.stub().resolves(
+        'https://canary.copilotcontent.affine.pro/blob-1-0?sig=test'
+      ),
+    } as never,
     {} as never,
     createTranscriptPromptService() as never,
     createSuccessfulTranscriptBridge('run-bridge', bridgeInputs) as never
@@ -447,6 +450,20 @@ test('transcriptTask runs native transcript recipe through action bridge when av
     slot: 'transcript.audio',
     builtInRouteId: 'Transcript audio structured',
   });
+  t.deepEqual(
+    (
+      bridgeInputs[0] as {
+        nativeInput: { input: { infos: unknown[] } };
+      }
+    ).nativeInput.input.infos,
+    [
+      {
+        url: 'https://canary.copilotcontent.affine.pro/blob-1-0?sig=test',
+        mimeType: 'audio/opus',
+        index: 0,
+      },
+    ]
+  );
   const messages = (
     bridgeInputs[0] as {
       step: {
@@ -459,7 +476,10 @@ test('transcriptTask runs native transcript recipe through action bridge when av
     infos: [{ mimeType: 'audio/opus', index: 0 }],
   });
   t.deepEqual(messages.at(-1)?.attachments, [
-    { attachment: 'data:image/png;base64,YXVkaW8=', mimeType: 'audio/opus' },
+    {
+      attachment: 'https://canary.copilotcontent.affine.pro/blob-1-0?sig=test',
+      mimeType: 'audio/opus',
+    },
   ]);
   t.like(complete.firstCall.args[1], {
     status: 'ready',
@@ -471,6 +491,7 @@ test('transcriptTask runs native transcript recipe through action bridge when av
     complete.firstCall.args[1].protectedResult.normalizedTranscript,
     '00:00:05 A: Kickoff'
   );
+  t.deepEqual(complete.firstCall.args[1].protectedResult.infos, payload.infos);
 });
 
 test('transcriptTask fails task when native action bridge reports an error event', async t => {

packages/backend/server/src/data/__tests__/migrations.spec.ts

@@ -5,6 +5,7 @@ import ava, { TestFn } from 'ava';
 import { createTestingModule, type TestingModule } from '../../__tests__/utils';
 import { Models } from '../../models';
 import { BackfillPermissionProjection1765500000000 } from '../migrations/1765500000000-backfill-permission-projection';
+import { BackfillTranscriptStorageKeys1786805802350 } from '../migrations/1786805802350-backfill-transcript-storage-keys';
 
 interface Context {
   module: TestingModule;
@@ -81,3 +82,44 @@ test('permission backfill repairs ownerless workspaces before runtime state proj
     { role: 'owner' }
   );
 });
+
+test('transcript backfill adds stable keys without removing compatibility URLs', async t => {
+  const payload = {
+    sourceAudio: { blobId: 'blob-1' },
+    infos: [
+      {
+        url: 'https://affine.example/api/copilot/blob/user-1/workspace-1/blob-1',
+        mimeType: 'audio/m4a',
+      },
+      {
+        url: 'https://example.com/external.m4a',
+        mimeType: 'audio/m4a',
+      },
+    ],
+  };
+  await t.context.db.aiTranscriptTask.create({
+    data: {
+      userId: 'user-1',
+      workspaceId: 'workspace-1',
+      blobId: 'blob-1',
+      status: 'failed',
+      recipeId: 'transcript.audio',
+      recipeVersion: 'v1',
+      inputSnapshot: payload,
+      protectedResult: payload,
+    },
+  });
+
+  await BackfillTranscriptStorageKeys1786805802350.up(t.context.db);
+  await BackfillTranscriptStorageKeys1786805802350.up(t.context.db);
+
+  const task = await t.context.db.aiTranscriptTask.findFirstOrThrow({
+    where: { blobId: 'blob-1' },
+  });
+  const expected = {
+    ...payload,
+    infos: [{ ...payload.infos[0], key: 'blob-1' }, payload.infos[1]],
+  };
+  t.deepEqual(task.inputSnapshot, expected);
+  t.deepEqual(task.protectedResult, expected);
+});

packages/backend/server/src/data/migrations/1786805802350-backfill-transcript-storage-keys.ts

@@ -0,0 +1,96 @@
+import { type Prisma, PrismaClient } from '@prisma/client';
+
+const BATCH_SIZE = 100;
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return !!value && typeof value === 'object' && !Array.isArray(value);
+}
+
+function backfillTranscriptStorageKeys(
+  payload: Prisma.JsonValue | null,
+  userId: string,
+  workspaceId: string
+): Prisma.InputJsonValue | undefined {
+  if (!isRecord(payload) || !Array.isArray(payload.infos)) {
+    return;
+  }
+
+  const prefix = `/api/copilot/blob/${encodeURIComponent(userId)}/${encodeURIComponent(workspaceId)}/`;
+  let changed = false;
+  const infos = payload.infos.map(info => {
+    if (!isRecord(info) || info.key || typeof info.url !== 'string') {
+      return info;
+    }
+
+    try {
+      const url = new URL(info.url);
+      if (!url.pathname.startsWith(prefix)) {
+        return info;
+      }
+      const key = decodeURIComponent(url.pathname.slice(prefix.length));
+      if (!key) {
+        return info;
+      }
+      changed = true;
+      return { ...info, key };
+    } catch {
+      return info;
+    }
+  });
+
+  return changed ? ({ ...payload, infos } as Prisma.InputJsonValue) : undefined;
+}
+
+export class BackfillTranscriptStorageKeys1786805802350 {
+  static async up(db: PrismaClient) {
+    let cursor: string | undefined;
+
+    while (true) {
+      const tasks = await db.aiTranscriptTask.findMany({
+        select: {
+          id: true,
+          userId: true,
+          workspaceId: true,
+          inputSnapshot: true,
+          protectedResult: true,
+        },
+        orderBy: { id: 'asc' },
+        take: BATCH_SIZE,
+        ...(cursor ? { cursor: { id: cursor }, skip: 1 } : {}),
+      });
+      if (!tasks.length) {
+        return;
+      }
+
+      const updates = tasks.flatMap(task => {
+        const inputSnapshot = backfillTranscriptStorageKeys(
+          task.inputSnapshot,
+          task.userId,
+          task.workspaceId
+        );
+        const protectedResult = backfillTranscriptStorageKeys(
+          task.protectedResult,
+          task.userId,
+          task.workspaceId
+        );
+        if (!inputSnapshot && !protectedResult) {
+          return [];
+        }
+        return db.aiTranscriptTask.update({
+          where: { id: task.id },
+          data: {
+            ...(inputSnapshot ? { inputSnapshot } : {}),
+            ...(protectedResult ? { protectedResult } : {}),
+          },
+        });
+      });
+
+      if (updates.length) {
+        await db.$transaction(updates);
+      }
+      cursor = tasks.at(-1)?.id;
+    }
+  }
+
+  static async down(_db: PrismaClient) {}
+}

packages/backend/server/src/data/migrations/index.ts

@@ -6,3 +6,4 @@ export * from './1751966744168-correct-session-update-time';
 export * from './1763800000000-rebuild-manticore-mixed-script-indexes';
 export * from './1765500000000-backfill-permission-projection';
 export * from './1765600000000-backfill-entitlement-projection';
+export * from './1786805802350-backfill-transcript-storage-keys';

packages/backend/server/src/plugins/copilot/storage.ts

@@ -59,14 +59,31 @@ export class CopilotStorage {
   ): Promise<StorageRuntimeGetObjectResult> {
     const name = `${userId}/${workspaceId}/${key}`;
     if (signedUrl) {
-      const presigned = await this.rt.presignGet('copilot', name);
-      if (presigned) {
-        return { redirectUrl: presigned.url };
-      }
+      const redirectUrl = await this.presignGet(userId, workspaceId, key);
+      if (redirectUrl) return { redirectUrl };
     }
     return this.rt.getObject('copilot', name);
   }
 
+  async presignGet(userId: string, workspaceId: string, key: string) {
+    return (
+      await this.rt.presignGet('copilot', `${userId}/${workspaceId}/${key}`)
+    )?.url;
+  }
+
+  keyFromUrl(userId: string, workspaceId: string, url: string) {
+    try {
+      const parsed = new URL(url);
+      const prefix = `/api/copilot/blob/${encodeURIComponent(userId)}/${encodeURIComponent(workspaceId)}/`;
+      if (parsed.pathname.startsWith(prefix)) {
+        return decodeURIComponent(parsed.pathname.slice(prefix.length));
+      }
+    } catch {
+      return;
+    }
+    return undefined;
+  }
+
   @CallMetric('ai', 'blob_delete')
   async delete(userId: string, workspaceId: string, key: string) {
     await this.rt.deleteObject('copilot', `${userId}/${workspaceId}/${key}`);

packages/backend/server/src/plugins/copilot/transcript/schema.ts

@@ -18,7 +18,8 @@ export const LegacyTranscriptionSchema = z.array(
 );
 
 export const AudioBlobInfoSchema = z.object({
-  url: z.string(),
+  key: z.string().min(1).optional(),
+  url: z.string().min(1),
   mimeType: z.string(),
   index: z.number().int().nullable().optional(),
 });

packages/backend/server/src/plugins/copilot/transcript/service.ts

@@ -46,10 +46,6 @@ export class CopilotTranscriptionService {
     private readonly realtime: RealtimePublisher
   ) {}
 
-  private parseTaskPayload(payload: unknown): TranscriptionPayloadV2 {
-    return TranscriptPayloadSchema.parse(payload);
-  }
-
   private buildTaskPublicMeta(payload: TranscriptionPayloadV2) {
     return {
       sourceAudio: payload.sourceAudio,
@@ -68,13 +64,10 @@ export class CopilotTranscriptionService {
     const infos: AudioBlobInfos = [];
     for (const [idx, blob] of blobs.entries()) {
       const buffer = await readStream(blob.createReadStream());
-      const url = await this.storage.put(
-        userId,
-        workspaceId,
-        `${blobId}-${idx}`,
-        buffer
-      );
+      const key = `${blobId}-${idx}`;
+      const url = await this.storage.put(userId, workspaceId, key, buffer);
       infos.push({
+        key,
         url,
         mimeType: sniffMime(buffer, blob.mimetype) || blob.mimetype,
         index: idx,
@@ -103,6 +96,47 @@ export class CopilotTranscriptionService {
     } satisfies TranscriptionPayloadV2;
   }
 
+  private async resolveAttachmentUrl(
+    userId: string,
+    workspaceId: string,
+    info: AudioBlobInfos[number]
+  ) {
+    if (info.url.startsWith('data:')) {
+      return info.url;
+    }
+
+    const key =
+      info.key ?? this.storage.keyFromUrl(userId, workspaceId, info.url);
+    if (!key) {
+      throw new Error('Transcript attachment cannot be resolved');
+    }
+
+    const signedUrl = await this.storage.presignGet(userId, workspaceId, key);
+    if (!signedUrl) {
+      throw new Error('Transcript attachment signing is not configured');
+    }
+    return signedUrl;
+  }
+
+  private async materializePayload(
+    userId: string,
+    workspaceId: string,
+    payload: TranscriptionPayloadV2
+  ) {
+    return {
+      ...payload,
+      infos: payload.infos
+        ? await Promise.all(
+            payload.infos.map(async info => ({
+              url: await this.resolveAttachmentUrl(userId, workspaceId, info),
+              mimeType: info.mimeType,
+              index: info.index,
+            }))
+          )
+        : payload.infos,
+    } satisfies TranscriptionPayloadV2;
+  }
+
   private async buildTranscriptActionMessages(payload: TranscriptionPayloadV2) {
     const prompt = await this.prompts.get(TRANSCRIPT_PROMPT_REF);
     if (!prompt) {
@@ -118,13 +152,12 @@ export class CopilotTranscriptionService {
           index: info.index ?? null,
         })) ?? null,
     };
-    const attachments =
-      payload.infos?.map(info => ({
-        role: 'user' as const,
-        content: `Audio attachment ${info.index ?? 0}`,
-        attachments: [{ attachment: info.url, mimeType: info.mimeType }],
-        params: { mimetype: info.mimeType },
-      })) ?? [];
+    const attachments = (payload.infos ?? []).map(info => ({
+      role: 'user' as const,
+      content: `Audio attachment ${info.index ?? 0}`,
+      attachments: [{ attachment: info.url, mimeType: info.mimeType }],
+      params: { mimetype: info.mimeType },
+    }));
     return [
       ...this.prompts.finish(prompt, {
         content: JSON.stringify(metadata),
@@ -205,7 +238,7 @@ export class CopilotTranscriptionService {
       );
     }
 
-    const payload = this.parseTaskPayload(task.protectedResult);
+    const payload = TranscriptPayloadSchema.parse(task.protectedResult);
     await this.runtime.assertRoute(
       'transcript.audio',
       {},
@@ -287,14 +320,19 @@ export class CopilotTranscriptionService {
       let bridgeFailed = false;
       let bridgeError = 'transcript native recipe failed';
       let finalResult: unknown = null;
-      const messages = await this.buildTranscriptActionMessages(payload);
+      const runtimePayload = await this.materializePayload(
+        task.userId,
+        task.workspaceId,
+        payload
+      );
+      const messages = await this.buildTranscriptActionMessages(runtimePayload);
       for await (const event of this.actionBridge.runStream({
         userId: task.userId,
         workspaceId: task.workspaceId,
         actionId: TRANSCRIPT_ACTION_ID,
         actionVersion: TRANSCRIPT_ACTION_VERSION,
         retryOf: retryOf ?? null,
-        inputSnapshot: payload,
+        inputSnapshot: runtimePayload,
         onRunCreated: async ({ runId }) => {
           await this.models.copilotTranscriptTask.markRunning(taskId, runId);
           this.publishTaskChanged(
@@ -329,7 +367,10 @@ export class CopilotTranscriptionService {
       if (bridgeFailed) {
         throw new Error(bridgeError);
       }
-      const parsedResult = TranscriptPayloadSchema.parse(finalResult);
+      const parsedResult = {
+        ...TranscriptPayloadSchema.parse(finalResult),
+        infos: payload.infos,
+      } satisfies TranscriptionPayloadV2;
       await this.models.copilotTranscriptTask.complete(taskId, {
         status: 'ready',
         actionRunId,