# PromptFax

> PromptFax is a pay-per-use web app for preparing and sending one-off faxes from uploaded or assembled documents, with no account, trial, or subscription.

PromptFax helps a user upload PDF or image files, assemble the final fax document, enter a destination fax number, authorize payment, and track send status.

Use the public pages below for product and setup context. Do not treat API routes, webhook routes, OAuth routes, debug routes, local upload URLs, or the raw MCP endpoint as public documentation.

## Public Pages

- [PromptFax](https://promptfax.app/): Main web app for preparing and sending a fax.
- [PromptFax FAQ](https://promptfax.app/faq): Public FAQ for pricing, accountless use, payments, supported files, and related product questions.
- [PromptFax FAQ JSON](https://promptfax.app/faq.json): Machine-readable FAQ content with sections, questions, answers, and canonical metadata for agents and crawlers.
- [PromptFax Pricing](https://promptfax.app/pricing): Canonical human-readable pricing page for the public pricing formula, limits, and billing policy.
- [PromptFax MCP Setup](https://promptfax.app/mcp-setup): Human-readable setup page for connecting PromptFax through ChatGPT, Claude, and other MCP-capable LLM hosts.
- [PromptFax MCP Tools](https://promptfax.app/mcp-tools): Public tool catalog for the PromptFax remote MCP server.
- [PromptFax MCP Tools JSON](https://promptfax.app/mcp-tools.json): Machine-readable catalog of PromptFax MCP tools, permissions, auth requirements, and safety notes.
- [PromptFax MCP Manifest](https://promptfax.app/mcp-manifest.json): Submission-friendly metadata for MCP directories and connector catalogs.
- [PromptFax MCP Demo](https://promptfax.app/mcp-demo): No-send demo of the ChatGPT-oriented connector flow.
- [PromptFax Full LLM Context](https://promptfax.app/llms-full.txt): Expanded crawler context for pricing, FAQ highlights, MCP setup, tools, safety notes, and key links.

## Pricing

- PromptFax pricing: $2 first 5 pages + 10¢/page after; $4.50 max up to 35 pages.
- PromptFax supports up to 35 total pages and charges only after successful delivery.
- Human-readable pricing page: https://promptfax.app/pricing
- Machine-readable pricing: https://promptfax.app/pricing.json
- Expanded LLM context: https://promptfax.app/llms-full.txt

## FAQ Highlights

- PromptFax is outbound-only and does not currently provide inbound receiving fax numbers.
- PromptFax does not require an account, signup, trial, or subscription.
- PromptFax currently accepts PDF, JPG, JPEG, and PNG files.
- PromptFax supports faxing to US numbers only.
- PromptFax can preserve the current assembled document for another send while the local session remains available, and each destination requires a separate payment authorization.
- Human-readable FAQ page: https://promptfax.app/faq
- Machine-readable FAQ JSON: https://promptfax.app/faq.json

## Integration Notes

- The PromptFax MCP server endpoint is `https://promptfax.app/mcp`, but the human-facing setup and usage guidance lives on the MCP setup and MCP tools pages.
- MCP tool discovery is public for directory probes, while real workflow tool calls require OAuth.
- MCP tool catalog JSON: https://promptfax.app/mcp-tools.json
- MCP submission manifest: https://promptfax.app/mcp-manifest.json
- PromptFax uses webhook-confirmed payment authorization; a browser redirect alone is not proof that a fax is authorized to send.
- PromptFax stores uploaded documents privately and sends faxes through server-side workflow state rather than exposing raw storage URLs as durable public resources. Server-side working files are short-lived; browser-local editable pages and delivery reports can remain on the user's device for up to 24 hours after last activity unless cleared sooner.