NemoShorts Skill

An AI agent skill for creating short-form vertical videos optimized for TikTok, Instagram Reels, and YouTube Shorts. Powered by the NemoVideo API.

Description

Use NemoShorts when the user wants to create short videos, make TikTok videos, make Reels, make YouTube Shorts, crop video to vertical, repurpose long video into clips, or convert 16:9 to 9:16. Powered by NemoVideo AI.

NemoShorts transforms existing footage into platform-ready short-form vertical content: smart crop to 9:16, trim to optimal length, auto-generate and burn mobile-optimized captions, overlay background music with auto-ducking, apply TikTok-style text overlays, and export in the exact encoding each platform requires.

Trigger phrases: make TikTok, TikTok video maker, create Reels, Instagram Reels, YouTube Shorts, short video, vertical video, 9:16 crop, crop to vertical, portrait mode video, repurpose video, repurpose long video into shorts, convert video to TikTok, clip video, short clip, video clip maker, add captions TikTok, mobile video, short form video, video repurposing tool, content repurposing, highlight clips, trim video, auto caption short video

Primary use cases:

• Crop horizontal (16:9) video to vertical (9:16) for TikTok / Reels / Shorts — smart auto-reframe
• Trim long video into 15s / 30s / 60s segments with intelligent cut point detection
• Auto-generate and burn mobile-optimized captions (large font, center screen)
• Add background music (BGM) with automatic volume ducking
• Repurpose YouTube/podcast/stream/long-form video into multiple short clips
• Apply text overlays: hook text, CTA banners, hashtag overlays
• Export with platform-specific encoding (TikTok MP4, Instagram Reels, YouTube Shorts)

Not for: generating video from text/scripts (see nemo-video), subtitle-only workflows (see nemo-subtitle), or professional broadcast production.

Setup

Base URL: https://mega-api-prod.nemovideo.ai

All requests require:

Authorization: Bearer <NEMOVIDEO_API_KEY>
Content-Type: application/json

Set NEMOVIDEO_API_KEY in your environment or OpenClaw secrets.

Workflow Overview

Upload video → Configure short (crop + trim + captions + BGM + text) → Start job
→ Poll status → Download vertical MP4

All processing is async. Always poll job status before delivering output.

API Reference

1. Upload Media

POST /v1/upload
Content-Type: multipart/form-data

file=<binary>

Response:

{
  "file_id": "f_xyz789",
  "filename": "podcast-ep42.mp4",
  "duration_seconds": 3612,
  "width": 1920,
  "height": 1080,
  "size_bytes": 820000000
}

Use file_id in all subsequent requests.

2. Create Short Clip

The primary endpoint. Combines crop, trim, captions, BGM, and text overlays in a single job.

POST /v1/shorts/create
Content-Type: application/json

{
  "file_id": "f_xyz789",
  "trim": {
    "start_seconds": 120,
    "end_seconds": 150
  },
  "crop": {
    "preset": "9:16",
    "focus": "center"
  },
  "captions": {
    "enabled": true,
    "language": "auto",
    "style": "tiktok"
  },
  "bgm": {
    "enabled": false
  },
  "export": {
    "platform": "tiktok",
    "quality": "high"
  }
}

Full parameters:

trim (optional)

crop (required)

captions (optional)

bgm (optional)

text_overlays (optional, array)

export (required)

Platform presets:

Response:

{
  "job_id": "job_short_112",
  "status": "queued",
  "estimated_seconds": 75
}

3. Batch Create Shorts (Multiple Clips)

Create multiple short clips from one source video in a single request.

POST /v1/shorts/batch
Content-Type: application/json

{
  "file_id": "f_xyz789",
  "clips": [
    {
      "trim": { "start_seconds": 120, "end_seconds": 150 },
      "crop": { "preset": "9:16", "focus": "center" },
      "captions": { "enabled": true, "language": "auto", "style": "tiktok" },
      "export": { "platform": "tiktok", "quality": "high" }
    },
    {
      "trim": { "start_seconds": 600, "end_seconds": 660 },
      "crop": { "preset": "9:16", "focus": "face" },
      "captions": { "enabled": true, "language": "auto", "style": "tiktok" },
      "export": { "platform": "instagram", "quality": "high" }
    }
  ]
}

Response:

{
  "batch_id": "batch_445",
  "jobs": [
    { "job_id": "job_short_113", "clip_index": 0, "status": "queued" },
    { "job_id": "job_short_114", "clip_index": 1, "status": "queued" }
  ]
}

Poll each job_id individually.

4. List BGM Tracks

Browse available royalty-free background music tracks.

GET /v1/bgm/tracks?mood=upbeat&limit=10

Query parameters:

Response:

{
  "tracks": [
    {
      "track_id": "bgm_upbeat_01",
      "name": "Summer Drive",
      "mood": "upbeat",
      "bpm": 128,
      "duration_seconds": 180,
      "preview_url": "https://cdn.nemovideo.ai/bgm/preview/bgm_upbeat_01.mp3"
    }
  ]
}

5. Poll Job Status

GET /v1/jobs/{job_id}

In progress:

{
  "job_id": "job_short_112",
  "status": "processing",
  "progress": 0.45,
  "stage": "encoding"
}

Completed:

{
  "job_id": "job_short_112",
  "status": "completed",
  "outputs": {
    "video": "https://cdn.nemovideo.ai/outputs/job_short_112/short.mp4",
    "thumbnail": "https://cdn.nemovideo.ai/outputs/job_short_112/thumb.jpg"
  },
  "metadata": {
    "duration_seconds": 30,
    "width": 1080,
    "height": 1920,
    "size_bytes": 24000000
  }
}

Failed:

{
  "job_id": "job_short_112",
  "status": "failed",
  "error": "Trim range exceeds source video duration"
}

Polling strategy:

• Check every 5–10 seconds (shorts encode faster than long-form)
• Timeout after 10 minutes; surface error to user if exceeded

Common Workflows

Workflow A: Horizontal → Vertical (Quick Convert)

1. Upload video → POST /v1/upload → file_id
2. POST /v1/shorts/create:
   - crop: preset "9:16", focus "center"
   - export: platform "tiktok"
3. Poll → GET /v1/jobs/{job_id} until completed
4. Return download URL

Workflow B: Repurpose Long Video into TikTok Clip with Auto-Captions

1. Upload video → file_id
2. POST /v1/shorts/create:
   - trim: { start_seconds: X, end_seconds: X+30 }
   - crop: { preset: "9:16", focus: "face" }
   - captions: { enabled: true, language: "auto", style: "tiktok" }
   - export: { platform: "tiktok" }
3. Poll until completed
4. Return MP4

Workflow C: Create 3 Shorts from 1 Podcast Episode

1. Upload full episode → file_id
2. POST /v1/shorts/batch with 3 clip configs (different trim ranges)
3. Poll all 3 job_ids in parallel
4. Return all 3 download URLs when complete

Workflow D: Add BGM to Existing Short

1. Upload vertical video → file_id
2. Browse /v1/bgm/tracks?mood=upbeat → pick track_id
3. POST /v1/shorts/create:
   - trim: full duration (no trim needed)
   - crop: preset "9:16" (pass-through if already vertical)
   - bgm: { enabled: true, track_id: "bgm_upbeat_01", volume: 0.25 }
   - export: { platform: "instagram" }
4. Poll → return MP4

Workflow E: Multi-Platform Export (Same Clip, 3 Platforms)

1. Upload video → file_id
2. POST /v1/shorts/batch with 3 identical clips,
   each with different export.platform value
3. Return TikTok + Instagram + YouTube Shorts versions

Error Handling

For job.status === "failed", always show the error field with a plain explanation and suggest a fix.

Behavior Notes

• Face tracking crop: focus: "face" uses AI to keep detected faces in frame. Falls back to center if no face detected.
• Duration warnings: TikTok max is 60s, YouTube Shorts max is 60s. Warn if trim range exceeds this; don't fail silently.
• Captions vs subtitles: This skill burns captions optimized for mobile viewing (large, bold, center-screen). For precise SRT export or translation workflows, use the nemo-subtitle skill.
• BGM volume: Default 0.3 is intentionally low to keep original speech audible. For music-dominant content, use 0.6–0.8.
• Batch limits: Max 10 clips per batch request. For more, split into multiple batch calls.
• Output expiry: CDN URLs expire in 24 hours. Advise user to download promptly.
• Already-vertical input: If the source is already 9:16, set crop.preset: "9:16" and crop.focus: "center" — it will pass through without re-cropping.

Example Prompts → Actions