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Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · AI / LLM tooling

PromptFax

Send a one-off fax from inside ChatGPT or Claude. Pay-per-use, $2-$4.50 per delivered fax.

Checks passed
12 / 22

2 failed · 8 not measured

Median response
440 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
8

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
222

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 440 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name promptfax-mcp.

  • Pass
    Lists tools

    tools/list returned 8 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 440 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 440 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    25 of 25 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Fail
    Website matches publisher

    The website host does not match the reverse-domain namespace.

  • Fail
    Source repo linked

    No repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-05-30T17:57:28.233218Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using PromptFax

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http promptfax https://promptfax.app/mcp

Capabilities

Tools 8

attach_document

Fallback/non-widget tool for binding a PromptFax document or one or more HTTPS PDF URLs into the current MCP session before requesting a quote. In ChatGPT widget sessions, prefer the widget's file controls after start_session instead of calling this tool unless the widget is unavailable or the user explicitly asks for fallback behavior.

Discovered
cancel

Use this when you need to cancel the active PromptFax send.

Discovered
checkout

Fallback/non-widget tool for starting external Stripe Checkout after the user accepts a pay-per-use quote. Payment authorization is required before PromptFax can send; PromptFax treats webhook-confirmed authorization, not browser redirect, as payment truth. In ChatGPT widget sessions, do not call this after start_session because the widget's Pay & send step opens Checkout.

Discovered
get_quote

Fallback/non-widget tool for creating a user-reviewable pay-per-use fax quote when you have a fax number and either an MCP session, a PromptFax documentId, or one or more HTTPS PDF URLs. A quote is required before Stripe Checkout and before any real fax transmission. In ChatGPT widget sessions, do not call this after start_session because the widget auto-quotes once the document and destination are ready.

Discovered
get_status

Use this when you need the latest PromptFax workflow state, quote/payment state, or fax transmission status.

Discovered
retry_failed_fax

Use this after a retry-eligible failed fax to queue another attempt under the existing authorization. You may supply a corrected destination.

Discovered
send_fax

Fallback/non-widget tool for sending after payment is authorized and the user explicitly wants to send now. In ChatGPT widget sessions, do not call this after start_session unless the widget is unavailable or the user explicitly asks for fallback behavior.

Discovered
start_session

Use this first when a user wants to send or price a fax. PromptFax is built for irregular, pay-per-use outbound faxing: every real send requires a user-reviewed quote and Stripe payment authorization before transmission. MCP clients should set hostType to identify their host: chatgpt, claude, browser, or other. In ChatGPT, pass official files[] file parameters first when they are available so PromptFax can immediately import files[].download_url; never pass a raw file_id or local path as the document. The ChatGPT widget opens for destination entry, automatic quote creation, Stripe Checkout, status tracking, and Choose PDF from ChatGPT fallback when automatic attachment is unavailable or fails. If no document is attached, tell the user to attach a document in the widget. The widget does not provide a document preview step. Do not tell ChatGPT users to get a quote; after the widget has a document and valid destination, tell them to verify the price and use Pay & send when ready. Standards-compatible MCP Apps hosts use the inline PromptFax picker, and text-only clients use the hosted PromptFax session page or attach_document with a fetchable HTTPS URL. Do not call get_quote, checkout, or send_fax for a ChatGPT widget session unless the user explicitly asks for fallback behavior or the widget is unavailable. Use get_status only for a textual status refresh.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected440 ms8