AnimateCaptions

npx add-mcp 'https://animatecaptions.com/api/mcp'

API & MCP

Let your code or AI agent caption videos. Send a video, choose a caption style and position, and download the finished MP4 when the job completes. Jobs use your plan's monthly uploads and appear in My projects, where you can still fine-tune them in the editor.

Your API keys

Connect an AI agent (MCP)

Add the hosted MCP server to any MCP client (Claude, Cursor, etc.) and pass your key as a bearer token:

{
  "mcpServers": {
    "animatecaptions": {
      "type": "http",
      "url": "https://animatecaptions.com/api/mcp",
      "headers": { "Authorization": "Bearer ac_live_YOUR_KEY" }
    }
  }
}

Tools: list_caption_styles, create_caption_job, start_caption_job, get_caption_job, wait_for_caption_job, download_captioned_video, list_caption_jobs, get_account. When the server runs locally (stdio), agents can pass a local file_path and download straight to disk.

REST API

Base URL https://animatecaptions.com/api/v1. Authenticate with Authorization: Bearer ac_live_….

1. Create a job from a public URL

curl -X POST https://animatecaptions.com/api/v1/jobs \
  -H "Authorization: Bearer $AC_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "source_url": "https://example.com/clip.mp4",
    "style": "beast",
    "position": "bottom",
    "customization": { "font_size": "large", "highlight_color": "#FFD400" }
  }'

…or upload a file

# 1) create → response has upload.url
curl -X POST https://animatecaptions.com/api/v1/jobs -H "Authorization: Bearer $AC_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"filename":"clip.mp4","file_size":10485760,"style":"punch","position":{"x":50,"y":80}}'

# 2) PUT the bytes (Content-Type must match upload.headers)
curl -X PUT "$UPLOAD_URL" -H "Content-Type: video/mp4" --upload-file clip.mp4

# 3) start processing
curl -X POST https://animatecaptions.com/api/v1/jobs/$JOB_ID/start -H "Authorization: Bearer $AC_API_KEY"

2. Poll status, then download

curl https://animatecaptions.com/api/v1/jobs/$JOB_ID -H "Authorization: Bearer $AC_API_KEY"
# status: awaiting_upload → queued → transcribing → rendering → completed | failed

curl -L -o captioned.mp4 https://animatecaptions.com/api/v1/jobs/$JOB_ID/download \
  -H "Authorization: Bearer $AC_API_KEY"

Job options

• style: caption style id (default beast). Full list: GET /api/v1/styles (no key needed).
• position: "top", "middle", "bottom", or {"x": 0-100, "y": 0-100} (centre of the captions, % of the frame).
• customization: font_size (small|medium|large), font_family, primary_color, highlight_color, active_word_color, uppercase, stroke_width, stroke_color, background_color, animation, ai_highlighter.
• theme_id: apply one of your saved themes. The spoken language is detected automatically.

Other endpoints

• GET /api/v1/jobs: list jobs (?limit=, ?before=, ?source=api)
• DELETE /api/v1/jobs/{id}: delete a job and its files
• GET /api/v1/me: plan, usage and limits

Errors are returned as {"error": {"code", "message"}}. Limits follow your plan: video length, file size (500 MB free / 2 GB paid), monthly uploads, and a watermark on the free plan.

FAQ

Is there an API for adding animated captions to videos?

Yes. The AnimateCaptions REST API at /api/v1 lets you create a caption job from a video URL or an upload, choose one of 37 caption styles and a position, poll the job status, and download the captioned MP4.

Can AI agents like Claude or Cursor caption videos with AnimateCaptions?

Yes. Add the hosted MCP server https://animatecaptions.com/api/mcp to any MCP client with your API key. The agent can then list styles, create caption jobs, wait for them, and return the download link.

How much does the AnimateCaptions API cost?

API keys are free. API jobs use your plan's monthly uploads: the free plan includes 3 videos per month up to 2 minutes with a watermark, and paid plans remove the watermark and raise the limits.

How long does a caption job take?

A short clip usually completes in one to two minutes: the audio is transcribed with word-level timing, then the animated captions are rendered into the video.

Which video formats does the API accept?

MP4 and MOV files, up to 500 MB on the free plan and 2 GB on paid plans, either as a public direct download link or uploaded to a presigned URL.

More: Caption API · Subtitle API · MCP server for video captions