transcribe-mcp

transcribe-mcp

Read web pages as clean markdown, transcribe audio and video, and find the silence worth cutting — from any MCP client. No account, no API key, no subscription. Your agent pays a fraction of a cent per call, in USDC, straight from a wallet you control.

{
  "mcpServers": {
    "transcribe": {
      "command": "npx",
      "args": ["-y", "transcribe-mcp@latest"],
      "env": { "TRANSCRIBE_MCP_WALLET_KEY": "0x..." }
    }
  }
}

On Windows, MCP clients can't start npx directly, so wrap it: "command": "cmd", "args": ["/c", "npx", "-y", "transcribe-mcp@latest"].

That is the whole setup. There is nothing to sign up for. It needs Node 20+. The video skill also needs ffmpeg.

One paid call at a time per wallet. The shop refuses a second paid request while one is still running (free, with "already in flight"). Call it sequentially, never in parallel.

Tools

tool	what it does	price
transcribe_url	a public audio/video url or a local audio file → text, timings, detected language	$0.05
find_dead_air	subtitles or timings (inline, or from_file a .json) → the spans worth cutting, and what you'd save	$0.002
fetch_page	a web page → clean markdown, links resolved. render: true for JavaScript pages	$0.005
shop_info	prices, limits and how payment works	free

find_dead_air eats exactly what transcribe_url returns, so the two chain: transcribe a talk, then cut the silence out of it.

"cuts": [{ "from": 2.55, "to": 10.85, "seconds": 8.3, "reason": "silence" }],
"stats": { "sourceSeconds": 20, "speechSeconds": 5.05, "wouldSavePercent": 74.75 }

transcribe_url and find_dead_air take save_to: an absolute path to a new .json file. The full result goes there and the reply is one line plus the receipt, so an hour of transcripts never floods your agent's context. It never overwrites a file, and a missing folder is refused before paying.

Cutting a whole video

For cutting a whole video end to end — split, transcribe, cut, synced subtitles — there is a ready agent skill in skills/dead-air-cutter.

What leaves your machine

• transcribe_url: the url, or the bytes of the file (audio only — .mp3 .wav .m4a .aac .ogg .opus .oga .flac; a video is refused, extract its audio with ffmpeg first).
• find_dead_air: the timings and text — from from_file, only start, end, text of each segment plus durationSeconds are sent, whatever else the file holds. If the file has a vtt field instead, that subtitle text is sent whole.
• fetch_page: the page URL.

This server talks only to https://transcribe.soboljem.cz. What the shop does with it, from its terms:

• Audio is never stored. It is transcribed by Cloudflare Workers AI and passes through Cloudflare's infrastructure.
• The result is kept briefly, up to about 8 hours. It is replayable for 15 minutes, then deleted by a sweep that runs four times a day. The replay is a shop-side safeguard that this client cannot use: every call signs a new payment. After a timeout or a "may have been charged" reply, check the wallet. Calling again pays again.
• A row per sale is kept with no automatic deletion: time, price, audio length, word and cut counts, the source hostname (never the full URL), and the paying wallet address and transaction hash, which are public on Base anyway. Ask via the terms page to have rows deleted.
• Payment settles through the PayAI facilitator on Base. On each sale, the shop owner gets a Telegram notification with the shortened payer address and source hostname.

The private key in TRANSCRIBE_MCP_WALLET_KEY never leaves the machine. It only signs.

Why pay-per-call instead of an API key

Because an agent cannot fill in a signup form. x402 is an HTTP-native payment: the server answers 402 Payment Required with a price, the client pays it, the request goes through. No dashboard, no key rotation, no minimum, no monthly bill. If you never call it, you never pay anything.

Settlement is USDC on Base (eip155:8453).

Running it without a wallet

It starts fine. shop_info answers, tools/list works, and the paid tools tell you what to set. Look before you fund anything.

What it will not do

• It will not overspend. Every call is filtered through a $0.10 ceiling; a quote above it is dropped and the client refuses to pay rather than guessing.
• It will not charge you for a refusal. Bad arguments are caught locally and never leave your machine. The shop is built not to settle error responses; that was verified on testnet (see its terms).
• It will not tell you "no charge" when it cannot know. If the connection drops mid-call, it says a payment may have gone out and to check the wallet before calling again.
• It will not lie about a sale. If the settlement header is missing, it says so instead of reporting a payment it cannot prove.

Files are capped at 800 KB. Oversized ones are refused for free, before payment. A local file is sent to the shop as bytes, so nothing has to be hosted first. For anything long, extract the audio small and split it — mono Opus at 16 kbps fits ~6 minutes per call:

ffmpeg -i talk.mp4 -vn -ac 1 -c:a libopus -b:a 16k -f segment -segment_time 360 part%03d.opus

Configuration

variable	meaning
TRANSCRIBE_MCP_WALLET_KEY	private key of a wallet holding a little USDC on Base. Required only for the paid tools.

Use a dedicated wallet with a few dollars in it, not your main one. This is true of every tool you hand a private key to, and it is true here.

Tests

npm test

MIT.