# SupWriter MCP Server

A remote Model Context Protocol (MCP) server that brings SupWriter's tools inside any MCP-compatible AI client — Claude, ChatGPT, Perplexity, Cursor, Claude Code, VS Code, Codex, OpenCode, and other agentic apps. The assistant can humanize, paraphrase, grammar-check, and detect AI text in the conversation, authenticated with the user's own SupWriter account.

Landing page: [supwriter.com/mcp](https://supwriter.com/mcp).

## Endpoint

- MCP server URL: `https://supwriter.com/api/mcp` (remote, Streamable HTTP).

## Tools

- **humanize** — rewrite AI-generated text so it reads as human-written.
- **paraphrase** — reword while preserving meaning (standard/formal/casual/academic/creative).
- **grammar_check** — fix grammar, spelling, and punctuation.
- **detect_ai** — classify text as AI vs human across 12 detectors with a sentence-level breakdown.

## Two ways to connect

1. **OAuth sign-in** (recommended for connector-based clients): Claude, ChatGPT, Perplexity, Cursor, VS Code. Add the URL above as a custom connector; sign in to SupWriter and approve the consent screen. Uses OAuth 2.1 (Dynamic Client Registration, PKCE, short-lived tokens).
2. **Direct API key** (for CLIs / headless agents that don't do OAuth): Claude Code, Codex, OpenCode. Create a key under Settings → API & MCP (Pro or Ultra) and send it as an `Authorization: Bearer sw_live_…` header.

Both methods hit the same endpoint and draw on your plan's word credits.

## Per-client setup guides

- [Claude](https://supwriter.com/mcp/claude)
- [ChatGPT](https://supwriter.com/mcp/chatgpt)
- [Perplexity](https://supwriter.com/mcp/perplexity)
- [Cursor](https://supwriter.com/mcp/cursor)
- [Claude Code](https://supwriter.com/mcp/claude-code)
- [VS Code](https://supwriter.com/mcp/vscode)
- [Codex](https://supwriter.com/mcp/codex)
- [OpenCode](https://supwriter.com/mcp/opencode)

## Billing

No separate MCP fee — calls draw on the word credits in your existing plan (one credit per word). AI detection is metered over MCP (one credit per word analyzed), the same as the REST API; it's free only inside the SupWriter web app.

## Related

- Developer REST API: [supwriter.com/developers](https://supwriter.com/developers.md)
- MCP server card: [supwriter.com/.well-known/mcp/server-card.json](https://supwriter.com/.well-known/mcp/server-card.json)
- Setup guide (blog): [Humanize AI text inside Claude](https://supwriter.com/blog/humanize-ai-text-in-claude-mcp)