# prepublish-mcp Audit a YouTube script **before** you record it, from inside your AI client. Prepublish is a remote MCP server. It reads a draft that does not exist as a video yet and returns hook, structure and pacing scores, the passages most likely to lose viewers, an inauthentic-content check, a YouTube policy pre-flight that cites YouTube's own published pages, and a words-to-runtime calculator built on measured speaking rates. Every other YouTube MCP server fetches the transcript of a video that is already published. This one reads the script you have not filmed. Free, anonymous, no API key, no account. ## Install **ChatGPT**: install the listed plugin, no configuration. [chatgpt.com/plugins/plugin_asdk_app_6aba148dbb6c81918fbc261b405c0c1c](https://chatgpt.com/plugins/plugin_asdk_app_6aba148dbb6c81918fbc261b405c0c1c), or open **Plugins** in the ChatGPT sidebar, search `Prepublish`, and select **Install plugin**. Works across plans on web, desktop and mobile. In ChatGPT the full audit renders as an inline report card; install from the directory rather than asking the chat to find it, then `@Prepublish` in a message. **Claude Code**, one command: ```bash claude mcp add --transport http prepublish https://mcp.prepublish.ai ``` **Cursor, VS Code, Windsurf, Claude Code project scope**, or anything that reads an `mcpServers` object: ```json { "mcpServers": { "prepublish": { "type": "http", "url": "https://mcp.prepublish.ai" } } } ``` **Claude Desktop**: add a custom connector under Customize, then Connectors, and paste `https://mcp.prepublish.ai`. **Codex CLI**, `~/.codex/config.toml`: ```toml [mcp_servers.prepublish] url = "https://mcp.prepublish.ai" ``` **Clients that can only launch a command** use the stdio bridge in this repository. It needs Node 20 or newer and forwards to the same endpoint: ```json { "mcpServers": { "prepublish": { "command": "npx", "args": ["-y", "prepublish-mcp"] } } } ``` Agents installing this on a user's behalf should read [`llms-install.md`](./llms-install.md). ### Check it worked Ask for a runtime estimate: *"Use prepublish to convert 1500 words into a runtime range."* `script_runtime` is local arithmetic, never rate limited, and returns three estimates. If that answers, the connection is good. ## Tools | Tool | Cost | What it returns | | --- | --- | --- | | `audit_script` | AI-backed | Full audit of a finished draft: hook, structure and pacing scores, an attention-risk map naming the passages most likely to lose viewers, and a rewrite. Returns the analysis and its id | | `get_audit` | free | Collect an earlier audit by `analysis_id` | | `audit_hook` | AI-backed | Per-sentence attention pull across the opening, curiosity gap, payoff distance, a grade, and rewritten alternatives | | `check_authenticity` | AI-backed | Reused, templated or mass-produced content risk, with the quotes that fired each signal | | `policy_preflight` | AI-backed | Which YouTube policy families a script touches, each citing YouTube's own page | | `script_runtime` | free, local | Words to runtime and runtime to a word budget, at 160, 181 and 201 words per minute measured across 349 videos | `audit_script` asks for an email address, because the full audit is released by email. The other five do not. ### What it does not do Every AI-backed response carries the same notice, and it is worth stating here too. These checks are text-only. They map relative attention risk inside an unrecorded script. They do not measure or predict the retention a published video will get, and no output here is a forecast of views, watch time or revenue. Nothing fetches a video, a transcript or a channel. Every tool reads text you pass it. ## Limits The free tier is published live at `GET https://mcp.prepublish.ai`, which returns a machine-readable server card with the current day's usage. | Limit | Default | | --- | --- | | AI-backed calls per UTC day, across the whole endpoint | 100 | | AI-backed calls per caller per 10 minutes | 6 | `script_runtime` is local arithmetic and never counts against either. A bearer token in `PREPUBLISH_TOKEN` raises the limits without changing the tool list. When the daily cap is reached the tool returns an error that tells the model not to retry and names the web alternative for that day. Failures return the next action rather than a stack trace. ## Transport and protocol Streamable HTTP, stateless. Supported revisions: `2025-11-25`, `2025-06-18`, `2025-03-26`, `2024-11-05`. A client asking for a supported revision gets it back; anything else negotiates to the newest one implemented, and the negotiated revision is reported identically in the response header and in the `initialize` result. The endpoint validates the `Origin` header. Requests without one, which is every non-browser client, are always served. A browser origin that is not `prepublish.ai` is refused with 403, as the transport specification requires. An unsupported `MCP-Protocol-Version` header is a 400. Aliases: `https://prepublish.ai/mcp` and `https://mcp.prepublish.ai/mcp` serve the same handler. ## Development The server itself lives in the Prepublish web application, not in this repository. What is here is the stdio bridge and the conformance suite that holds the hosted endpoint to the specification. ```bash npm install npm run build MCP_URL=https://mcp.prepublish.ai npm test ``` The suite drives the endpoint with the official MCP SDK **client** over Streamable HTTP, so the wire format is checked against the reference implementation rather than against our own assumptions. It covers the handshake, tool discovery, schema shape, both directions of `script_runtime`, unknown-tool errors, the server card, batching rejection, notification handling, protocol negotiation in both directions, Origin validation, protocol version validation, and the stdio bridge round trip. One AI-backed test is skipped unless `MCP_TEST_BILLABLE=1`, because a real call costs money and writes a row. `PREPUBLISH_MCP_URL` overrides the upstream endpoint for the bridge. The bridge adds and hides nothing: a test asserts its tool list equals the hosted one, so adding a tool on the server needs no release here. ## Registry Published to the official MCP registry as `ai.prepublish/script-audit`, a remote-only entry under the DNS-verified `ai.prepublish` namespace. See [`server.json`](./server.json). [![M8ven Score](https://m8ven.ai/badge/mcp/prepublish-prepublish-mcp-bcz7se)](https://m8ven.ai/mcp/prepublish-prepublish-mcp-bcz7se) ## Links - ChatGPT plugin: - Documentation: - Privacy: - Contact: ## License MIT. See [LICENSE](./LICENSE).