| 1 | # Director Merge Protocol |
| 2 | |
| 3 | This document defines the Echo Director contract for final video merge jobs. Echo Server owns the |
| 4 | FFmpeg operation, the resulting video, and its artifact metadata. |
| 5 | |
| 6 | ## Request |
| 7 | |
| 8 | Nanobot submits merge jobs with: |
| 9 | |
| 10 | - Method: `POST` |
| 11 | - Path: `/merge` |
| 12 | - Content type: `application/json` |
| 13 | - Protocol version: `director-http-v1` |
| 14 | |
| 15 | Request body: |
| 16 | |
| 17 | ```json |
| 18 | { |
| 19 | "protocol_version": "director-http-v1", |
| 20 | "operation": "merge_shot", |
| 21 | "job": { |
| 22 | "job_id": "merge-work-20260429-demo-final-20260429T140000Z", |
| 23 | "work_id": "work-20260429-demo", |
| 24 | "target": "final", |
| 25 | "created_at": "2026-04-29T14:00:00Z" |
| 26 | }, |
| 27 | "callback": { |
| 28 | "event_type": "director_remote_result", |
| 29 | "protocol_version": "director-http-v1", |
| 30 | "operation": "merge_shot", |
| 31 | "work_id": "work-20260429-demo", |
| 32 | "job_id": "merge-work-20260429-demo-final-20260429T140000Z", |
| 33 | "target": "final", |
| 34 | "channel": "websocket", |
| 35 | "chat_id": "cafc067e-c8e3-4fb2-af11-62bc5c04e8d2", |
| 36 | "session_key": "websocket:cafc067e-c8e3-4fb2-af11-62bc5c04e8d2", |
| 37 | "inject_back_to_agent": true, |
| 38 | "url": "http://127.0.0.1:18791/api/director/merge-shot/callback" |
| 39 | }, |
| 40 | "payload": { |
| 41 | "work_id": "work-20260429-demo", |
| 42 | "shot_ids": [1, 2], |
| 43 | "shots": [ |
| 44 | { |
| 45 | "shot_id": 1, |
| 46 | "version_id": "r2v-version-id-for-shot-001" |
| 47 | } |
| 48 | ] |
| 49 | } |
| 50 | } |
| 51 | ``` |
| 52 | |
| 53 | The backend acknowledgement should be JSON: |
| 54 | |
| 55 | ```json |
| 56 | { |
| 57 | "accepted": true, |
| 58 | "task_id": "remote-merge-task-id", |
| 59 | "version_id": "remote-merge-task-id", |
| 60 | "status": "queued", |
| 61 | "status_url": "https://backend.example/version/remote-merge-task-id" |
| 62 | } |
| 63 | ``` |
| 64 | |
| 65 | `remote_task_id` may also be returned as `task_id`. |
| 66 | |
| 67 | ## Callback |
| 68 | |
| 69 | When the merge completes, the backend calls the callback URL from the request: |
| 70 | |
| 71 | - Method: `POST` |
| 72 | - Path: `/api/director/merge-shot/callback` |
| 73 | - Content type: `application/json` |
| 74 | |
| 75 | Successful callback body: |
| 76 | |
| 77 | ```json |
| 78 | { |
| 79 | "work_id": "work-20260429-demo", |
| 80 | "job_id": "merge-work-20260429-demo-final-20260429T140000Z", |
| 81 | "status": "completed", |
| 82 | "session_key": "websocket:cafc067e-c8e3-4fb2-af11-62bc5c04e8d2", |
| 83 | "channel": "websocket", |
| 84 | "chat_id": "cafc067e-c8e3-4fb2-af11-62bc5c04e8d2", |
| 85 | "remote_task_id": "remote-merge-task-id", |
| 86 | "result": { |
| 87 | "artifact_url": "http://127.0.0.1:8221/media/merges/remote-merge-task-id.mp4", |
| 88 | "result_url": "http://127.0.0.1:8221/media/merges/remote-merge-task-id.mp4" |
| 89 | }, |
| 90 | "completed_at": "2026-04-29T14:02:00Z" |
| 91 | } |
| 92 | ``` |
| 93 | |
| 94 | The Agent treats the returned URL as an opaque media location; filesystem and object-storage details |
| 95 | remain inside Echo Server. |
| 96 | |
| 97 | Failed callback body: |
| 98 | |
| 99 | ```json |
| 100 | { |
| 101 | "work_id": "work-20260429-demo", |
| 102 | "job_id": "merge-work-20260429-demo-final-20260429T140000Z", |
| 103 | "status": "failed", |
| 104 | "session_key": "websocket:cafc067e-c8e3-4fb2-af11-62bc5c04e8d2", |
| 105 | "channel": "websocket", |
| 106 | "chat_id": "cafc067e-c8e3-4fb2-af11-62bc5c04e8d2", |
| 107 | "remote_task_id": "remote-merge-task-id", |
| 108 | "error": "merge failed" |
| 109 | } |
| 110 | ``` |
| 111 | |
| 112 | Nanobot applies completed callbacks to `state.final_output_url` or `state.final_output_path`, clears the pending merge job, publishes a workplace update, and exposes the final video in the workplace timeline after the shot list. |
| 113 |