SendThisFax

Send real faxes to EU institutions from your AI agent, via a pay-per-fax checkout link or a prepaid API key.

访问 sendthisfax.com

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Send faxes from your AI agent

SendThisFax speaks MCP. Connect Claude Code, Codex or any MCP client and let your agent prepare the fax — you only click the payment link.

New to this? Read the step-by-step guide.

Connect

The MCP endpoint is https://www.sendthisfax.com/mcp (streamable HTTP, no authentication required).

Claude Code

claude mcp add --transport http sendthisfax https://www.sendthisfax.com/mcp

Codex (~/.codex/config.toml)

[mcp_servers.sendthisfax]
url = "https://www.sendthisfax.com/mcp"

How it works

  1. Your agent uploads the PDF over plain HTTP — curl, fetch, any client:
curl -F "[email protected]" https://www.sendthisfax.com/api/upload
  1. It calls the send_fax tool with the recipient fax number, and receives a one-time payment link.
  2. You open the link and pay — no account, no subscription.
  3. The agent polls get_fax_status until the fax is delivered. If delivery fails, you are refunded automatically.

Tools

  • get_price — price quote for a page count and billing country, VAT included.
  • send_fax — submits an uploaded PDF and returns the payment link.
  • get_fax_status — live status: pending, sending, delivered or failed.
  • check_balance — remaining prepaid credit (API-key mode only).

Autonomous mode with an API key

With prepaid credits there is no payment link at all: connect with your API key and send_fax debits your balance and sends immediately. Failed faxes are re-credited.

claude mcp add --transport http sendthisfax https://www.sendthisfax.com/mcp \
  --header "Authorization: Bearer stf_live_..."

Buy credits and get your key on the API credits page. A REST API is also available: POST https://www.sendthisfax.com/api/v1/faxes. Check your balance and fax history on the dashboard.

Good to know

  • PDFs up to 50 MB and 1000 pages; encrypted PDFs are rejected.
  • Pricing is €5.00 for up to 5 pages plus €0.50 per extra page, plus VAT by billing country — same as on the website.
  • A plain JSON status endpoint is also available: GET https://www.sendthisfax.com/api/fax/:fax_id
  • Use +19898989898 as recipient for integration tests.