bigapiMCP setup

Connect bigapi to Claude, ChatGPT and coding agents

bigapi gives an AI assistant 40 file operations it cannot do itself: Markdown or HTML to PDF, merge, split and compress PDFs, OCR, Office to PDF, redaction, tables from PDFs, C2PA labels and more. The hosted MCP server needs no installation. You need a bigapi.dev API key: one POST https://api.bigapi.dev/v1/keys gives you one with 100 free operations, no signup. After that every successful operation costs USD 0.01 from prepaid credit; failed operations are free.

Two addresses

Address	Sign-in	For
https://api.bigapi.dev/mcp/connect	OAuth 2.1: you paste your API key once on our sign-in page	Claude.ai, ChatGPT and other chat apps with custom connectors
https://api.bigapi.dev/mcp	Header Authorization: Bearer <key>	Claude Code, Codex, Gemini CLI, Cursor and agents you build yourself

Transport: Streamable HTTP (JSON-RPC over HTTPS POST). Servers in Germany.

Claude.ai

1. Open Settings → Connectors → Add custom connector.
2. Name: bigapi, URL: https://api.bigapi.dev/mcp/connect.
3. Click Connect. On the bigapi page paste your API key (bigapi_…) and confirm.
4. In a chat: “Turn this Markdown into a PDF with bigapi” or attach a PDF and ask to compress it.

ChatGPT

1. Settings → Apps & Connectors → Advanced: enable developer mode (needed for custom apps while bigapi is not yet listed in the directory).
2. Create app: name bigapi, URL https://api.bigapi.dev/mcp/connect, authentication OAuth.
3. Sign in with your API key on the bigapi page.
4. Attached files are passed to bigapi through ChatGPT's file link; results come back as a download link.

Claude Code

claude mcp add --transport http bigapi https://api.bigapi.dev/mcp \
  --header "Authorization: Bearer $BIGAPI_KEY"

Codex

In ~/.codex/config.toml, with the key in the environment variable BIGAPI_KEY:

[mcp_servers.bigapi]
url = "https://api.bigapi.dev/mcp"
bearer_token_env_var = "BIGAPI_KEY"

Gemini CLI

gemini mcp add --transport http \
  --header "Authorization: Bearer $BIGAPI_KEY" bigapi https://api.bigapi.dev/mcp

Tested on 6 October 2026 with Gemini CLI 0.62. For personal Google accounts the CLI no longer accepts “Sign in with Google”; start it with a Gemini API key from Google AI Studio instead. Gemini only enables MCP servers in folders you have marked as trusted, so start it from a project folder and choose “Trust folder”. The Gemini app itself does not accept custom MCP servers for personal accounts; Gemini Enterprise does.

Windows behind antivirus HTTPS scanning (for example Kaspersky): if npm or Gemini report SELF_SIGNED_CERT_IN_CHAIN, set NODE_OPTIONS=--use-system-ca so Node trusts the Windows certificate store. Do not switch certificate checks off.

Cursor and other MCP clients

{
  "mcpServers": {
    "bigapi": {
      "url": "https://api.bigapi.dev/mcp",
      "headers": { "Authorization": "Bearer bigapi_…" }
    }
  }
}

Prefer a local server? npx -y @bigapi/mcp runs one tool per operation on your machine and fetches its own key.

Tools

Tool	What it does	Kind	Cost
find_tool	Describe a file task in plain words and get the matching operation with a ready-to-run example.	read-only	free, no key
run_operation	Runs one operation (op), with files in file / files and options in params. Creates a new result; never changes your original. Some operations load public web pages you name (render with a URL, screenshot, url/to-markdown).	write, open world, not destructive	USD 0.01 per operation (per page for OCR, Office, PDF to Markdown, tables, compare, redact)
get_balance	Remaining credit and free operations of the connected account.	read-only	free
get_pricing	Price list of all operations.	read-only	free, no key

Files in and out

• In: {"download_url": "https://…"} (HTTPS only, public addresses only, no redirects, up to 25 MB) or {"content_base64": "…", "file_name": "a.pdf"}. Input files are held in memory only.
• Out: data results (JSON, Markdown) come back as text. Files come back as a download link that works once and expires after 15 minutes; the file is deleted after the download or when the link expires.
• Notes: if bigapi adjusted something (an invalid option replaced by the default, PDF pages without text, low QR contrast), the answer ends with a line “Note from bigapi: …”.

Costs and limits

• Credit is bought only on bigapi.dev, never inside Claude or ChatGPT. It never expires.
• Every key has a monthly spending cap (default USD 10, adjustable in the console). Once the cap or the credit is used up, further calls are refused with a clear message instead of being charged.
• Errors cost nothing. Check your balance any time with get_balance or in the console.

Privacy and disconnecting

We keep no file contents. Your API key is stored encrypted for the connection; access tokens are valid for 30 days, refresh tokens for 180 days. To disconnect, remove the connector in your app, or revoke the key in the console: every connection using it stops at once. Details: privacy policy, section MCP connector.

Support

support@bigapi.dev · Artoption GmbH, Hamburg, Germany

Last updated: 6 October 2026.