Katto README

The full upstream README, mirrored for reference. Install config, tool schemas, adoption signals and our own overview live on the Katto listing page.

katto-mcp

npm version npm downloads license MCP Registry

The AI video clipping MCP server. Turn long videos into scored, captioned, vertical 9:16 short clips from any MCP client (Claude, Cursor, Claude Code, ChatGPT, VS Code, and other conformant clients). Drop in a YouTube link, a podcast, or a Twitch VOD and get publish-ready shorts back through natural conversation.

Powered by Katto, an AI video clipper that turns long-form video (podcasts, interviews, streams, webinars) into short-form clips for TikTok, Reels and YouTube Shorts. Katto is a flat-priced, no-credits alternative to tools like OpusClip: the Creator plan's 25-video monthly quota covers videos up to 90 minutes each. API and MCP access is included on every plan, including the free one (2 videos/month), not gated behind a paid or enterprise tier.

What it does

Ask your agent something like "clip the best moments from this podcast and reframe them for TikTok" and Katto will:

  • find the strongest 30 to 90 second moments in a long video and score each clip 0 to 100 on Hook, Flow, Value and Trend,
  • reframe to vertical 9:16 with face tracking, split-screen for two speakers, and stacked layouts for gaming,
  • burn animated captions (auto-captioned in 99 languages via Whisper large-v3; word-by-word timing in 41 of them, sentence-level in the rest) and optionally dub into 19 languages,
  • and hand back publish-ready MP4 files plus SRT caption urls.

Typical uses: repurpose a YouTube video into shorts, turn a podcast episode into clips, cut highlights from a Twitch VOD, or convert a long interview into vertical social posts.

Two ways to connect

Hosted (zero-install, recommended)

Point any OAuth-capable MCP client at the hosted endpoint and sign in with your Katto account. The API key never touches your disk, and you can revoke access anytime:

Code
https://mcp.katto.tech/mcp   (Streamable HTTP, OAuth 2.1)

Local (npx)

For Cursor, CI and scripts. Create an API key at katto.tech/dashboard/api-keys, then add the server to your MCP client config:

config.json
{
  "mcpServers": {
    "katto": {
      "command": "npx",
      "args": ["-y", "katto-mcp"],
      "env": { "KATTO_API_KEY": "sk_live_..." }
    }
  }
}

The hosted endpoint above also accepts Authorization: Bearer sk_live_... directly for key-based clients.

Install per client

Claude Code (hosted, OAuth):

Terminal
claude mcp add --transport http katto https://mcp.katto.tech/mcp

Claude Desktop — Settings → Connectors → Add custom connector → https://mcp.katto.tech/mcp, then sign in. (Or add the npx block above to claude_desktop_config.json.)

Cursor — Settings → MCP → Add → paste the npx JSON block above (uses KATTO_API_KEY).

VS Code (MCP extension) — add the same npx block to your MCP settings, or point it at the hosted URL if your client supports remote OAuth servers.

ChatGPT (Developer mode / connectors) — add a custom connector with URL https://mcp.katto.tech/mcp.

Gemini CLI (extension, hosted, OAuth):

bash
gemini extensions install https://github.com/miracleweasel/katto-mcp

then /mcp auth katto to sign in. The extension (gemini-extension.json + GEMINI.md) points at the hosted endpoint; no key on disk. Manual alternative in ~/.gemini/settings.json: "mcpServers": { "katto": { "httpUrl": "https://mcp.katto.tech/mcp" } }.

Antigravity CLI (agy, Gemini CLI's successor) — add the hosted server to ~/.gemini/config/mcp_config.json: "mcpServers": { "katto": { "serverUrl": "https://mcp.katto.tech/mcp" } }, or run agy plugin import gemini after installing the Gemini CLI extension above.

Tools

29 tools, in five groups: nine for clipping, eight for editing, four for publishing, one for feedback, seven for account and reference.

Clipping:

  • katto_create_clip_job(url | upload_id, config?) clip a long video from a public link (YouTube, Twitch, Kick, Vimeo, Zoom, Google Drive, Dropbox, Loom, LinkedIn, Facebook, Rumble, Dailymotion, Medal.tv, or a direct https link to a video file) or a file uploaded with katto_upload_video. Returns a job id.
  • katto_upload_video(filename, content_type, size) clip a local file: returns a presigned upload url to PUT the file to, then katto_create_clip_job with upload_id.
  • katto_get_job(id) poll until status is completed; clips holds the finished MP4 + caption (SRT) urls.
  • katto_get_clips(id) just the finished clips of a job (MP4 + SRT + title + virality score).
  • katto_get_transcript(id) the job's timestamped transcript segments.
  • katto_list_jobs(limit?, cursor?, status?) your recent jobs, newest first (keyset pagination).
  • katto_cancel_job(id) cancel a running job and refund the monthly video slot.
  • katto_create_clip(id, start_seconds, end_seconds, aspect?, auto_reframe?) a new clip from any time range of the source (3-180 s, up to 10 per video, within 7 days). No quota.
  • katto_more_clips(id, count?) render more clips from the moments Katto scored but did not render. No quota.

Editing (no quota):

  • katto_rerender_clip(id, clip_index, layout_mode?, caption_style?) re-render one clip with a new reframe layout or caption style.
  • katto_dub_clip(id, clip_index, languages) re-render a clip dubbed into one or more of 19 languages.
  • katto_get_rerender(id, rerender_id) poll a re-render for the new versioned clip url.
  • katto_translate_captions(id, clip_index, language) re-render a clip with its captions translated into one of 19 languages (Creator).
  • katto_retitle_clip(id, clip_index, style? | title?) AI-regenerate a clip's title, or save your own.
  • katto_adjust_clip(id, clip_index, start_offset_seconds?, end_offset_seconds?) trim or extend a clip (relative to its original bounds, 3-180 s; extending works within 7 days of the job) and re-render it.
  • katto_add_hook(id, clip_index, text?, position?, duration?) burn a hook over the first seconds; without text, Katto's AI writes one.
  • katto_generate_post_text(id, clip_index, platform?) AI-written title / caption / hashtags per platform, ready for katto_publish_clip. Nothing is posted.

Publishing:

  • katto_list_connected_accounts() which of the 7 platforms are connected in Katto, and whether one needs a reconnect. Call it before publishing.
  • katto_publish_clip(id, clip_index, platform, caption?, schedule_at?, ...) post a clip now or later to a social account connected in the Katto dashboard (YouTube, TikTok, LinkedIn, Instagram, Bluesky, Mastodon, Threads). Posts publicly: clients should confirm with the user first (annotated destructive). Paid plans; scheduling on Creator.
  • katto_list_scheduled_posts(status?, limit?, cursor?) the scheduled posts, newest first, with their status and error.
  • katto_cancel_scheduled_post(scheduled_post_id) cancel a post that has not gone out yet (annotated destructive).

Feedback:

  • katto_rate_clip(id, clip_index, rating, reason?) record the user's good/bad verdict on a clip, like the thumbs on the results page.

Account and reference:

  • katto_get_usage() your plan and remaining monthly video quota.
  • katto_get_account() the connected account, this key's scopes, and quota.
  • katto_get_brand_kit() your saved brand kits (colors, caption font, layout, watermark).
  • katto_get_webhook_secret() your webhook signing secret and how to verify signed callbacks (returns a secret — treat it like a credential).
  • katto_list_sources() the link sources Katto can clip from, with an example url each.
  • katto_list_clip_lengths() the valid target clip-length buckets.
  • katto_list_caption_styles() the caption-style presets you can pass as caption_style when creating a job or re-rendering a clip.

Jobs draw from your Katto plan's monthly video quota (25 on Creator, 10 on Solo, 2 on Free), with source videos up to 90, 60 and 30 minutes respectively. The underlying REST API also supports Idempotency-Key safe retries, read-only scoped keys, and signed HMAC webhooks. See the docs.

Env

varrequireddefault
KATTO_API_KEYyes(none)
KATTO_API_URLnohttps://katto.tech

Full docs: katto.tech/docs/api

Security & data

  • Hosted auth is OAuth 2.1 — the API key is never written to your disk, and you can revoke a connected client anytime from your Katto account settings.
  • Local auth uses a scoped sk_live_ key you create yourself; keys can be read-only, and the npx server only sends it to KATTO_API_URL (default katto.tech) over HTTPS.
  • katto_get_webhook_secret returns a signing secret — handle it like any credential; it is only needed to verify inbound webhook signatures.

Also listed on

Public Discovery

Katto – AI video clipping MCP server: turn long videos and podcasts into scored, captioned, reframed 9:16 clips, from any MCP client (Claude, Cursor, ChatGPT). Hosted, OAuth 2.1, no API key on disk.

Intents this server covers: AI video clipping MCP server, MCP server for short-form video, MCP to turn podcasts into clips, video clipping for AI agents (Claude / Cursor / ChatGPT).

Example prompts:

  1. "Clip the best moments from this podcast episode and reframe them for TikTok: https://youtube.com/watch?v=…"
  2. "Check the status of my last clipping job and give me the download links for the finished clips."
  3. "Take clip 2 from that job, dub it into Spanish and re-render it with the Bold caption style."

License

MIT — see LICENSE.