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Oh Fax MCP server

Which MCP servers are Oh Fax's own, from the official registry and from asking its own domain, whether they answer, and what they offer. A program checked each of these, nobody copied them from a product page.

read 2026-10-24

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Whose server it is
  • Registry namecom.ohfax/ohfaxverified in the MCP registry

The registry name sits under ohfax.com. The registry only lets a publisher use that namespace after proving control of the domain through DNS or HTTP.

When we asked itchecked 2026-10-24
  • Stateanswerschecked 2026-10-24
  • Tools4
  • Server calls itselfohfax
  • Server version0.1.0
  • Protocol version2025-06-18

On 2026-10-24 the server answered initialize and tools/list without a sign-in. First answer in 359 ms.

Should an agent connect itNot proven either way yet
  • Its tools do every use case we checked: Send a PDF to a US or Canadian fax number; Track delivery of a sent fax with a receipt.
  • Checked on 3 of the 7 days it takes to judge reliability.

Once connected

  • For "Send a PDF to a US or Canadian fax number", the likely first call is quote_fax.
  • For "Track delivery of a sent fax with a receipt", the likely first call is get_fax_status.
  • send_fax change data without a sign-in: anyone with the address can call them.
  • Parameters are untyped or undescribed in 2 of 4 tools: check arguments before calling.

Said by rules from the measurements above. The likely first call is a model's pick from the tool list; read its description before relying on it.

Measured dailydaily checks: 3, the first on 2026-10-25
  • INITE MCP scoreafter a weeka score needs 7 daily checks: 3 so far
  • What an agent can do with it2 of 2 use cases
  • Answeredmeasuring3 of the 7 daily checks it takes to print a share
  • Median first answer390 ms
  • Space in an agent's context≈ 517 tokensthe definitions of all its tools (4), which an agent carries on every turn
  • Tool definitionsA · 92 of 100
  • Typed results0 of 4 toolsdeclared outputSchema: results come typed, read once
  • Parameters without a description: in 2 of 4

What an agent can do with it

  • can do · Send a PDF to a US or Canadian fax number
  • can do · Track delivery of a sent fax with a receipt
  • not sure · Let an AI agent send faxes over HTTP

Each of the product's use cases, put to Jev against this server's tool list: can an agent do it with these tools?

Worth a look

  • Tools that change data, on a server that answers without a sign-in: send_fax

A program checks the server once a day: initialize and tools/list, no model. Tokens are the definitions' length at about four characters a token. The grade averages six checks of every tool's name, description, schema and annotations; it says how well the tools are described, not whether they work. The score weighs what was measured and nothing else: answering (25%), doing the product's job (25%), definitions (20%), context (10%), use (10%) and how readily a client connects (10%). A part that was not measured is left out, and a hidden instruction caps the score at 40. The state of vendors' MCP servers: method and numbers →

Tools it offers4 tools · read 2026-10-24
  • quote_fax

    Price a fax before committing to anything. Validates the destination and the document, counts pages, and returns prices for card, balance, and stablecoin plus a payment link. Free, and sends nothing. Always call this before send_fax.

  • send_fax

    Returns the authorization instructions for sending a previously quoted fax. THIS ACTION COSTS MONEY AND CANNOT BE UNDONE: paying the returned link transmits a real document to a real fax machine. This tool itself does not charge you — it…

  • get_fax_status

    Current delivery state of a fax: awaiting_payment, paid, submitted, sending, delivered, or failed. Failed faxes include a reason you can act on.

  • get_fax_receipt

    Verifiable delivery receipt for a completed fax. Available once the fax has reached a final state. Use this to prove the workflow finished.

How to connect

Add the server to your MCP client config. Claude Desktop, Cursor and most other clients read this shape:

{
  "mcpServers": {
    "ohfax": {
      "type": "http",
      "url": "https://app.ohfax.com/mcp"
    }
  }
}

Add it

Claude Code, in a terminal

claude mcp add --transport http ohfax https://app.ohfax.com/mcp

Add to CursorAdd to VS Code

claude.ai, ChatGPT and other clients: add https://app.ohfax.com/mcp as a custom connector in the settings.

Each line is something a program found when it went looking: the registry entry, the server's own answer, a spec that parses. A missing line means we did not find it, not that it does not exist.