# SingleFax

> Pay-per-fax API and MCP tools for sending faxes from apps and AI agents.

## Product

- Retail send: quote by page count, shared U.S. outbound Telnyx line, destinations Telnyx supports
- Pricing (domestic base): $0.99 for up to 10 billable pages, then +$0.08/page (cap 50)
- Dedicated inbound numbers are separate (weekly / lifetime / monthly)
- Developer API: `/api/v1` with API keys + prepaid credits
- MCP: `https://singlefax.com/mcp` (Streamable HTTP + OAuth) — install from `/agents`
- MPP: `/mpp.md` — REST `POST /api/v1/machine/faxes` (HTTP 402 + Stripe SPT). Cursor cannot pay this without Link CLI.

## Key URLs

- [OpenAPI](https://singlefax.com/openapi.json)
- [Agents](https://singlefax.com/agents)
- [MPP guide](https://singlefax.com/mpp.md)
- [Agents markdown](https://singlefax.com/agents.md)
- [Send a fax](https://singlefax.com/send-or-receive-fax)

## Notes for agents

- Chat clients: add MCP, then `create_upload` → `create_fax_draft` (Checkout or subscription pool).
- Do not use MCP `create_machine_fax` with Link CLI; pay `POST /api/v1/machine/faxes` instead.
- Do not invent HIPAA claims; PHI is website HIPAA Secure + BAA only.
- Never log fax numbers, emails, filenames, or document contents.