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8 clients · secrets stay placeholders

JSON (mcpServers)Claude CodeCodexOpenCodeCursorVS CodeGemini CLIGoose

{
  "mcpServers": {
    "factreason": {
      "type": "http",
      "url": "https://www.factreason.com/mcp"
    }
  }
}

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

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

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "factreason": {
      "type": "remote",
      "url": "https://www.factreason.com/mcp",
      "enabled": true
    }
  }
}

{
  "mcpServers": {
    "factreason": {
      "type": "http",
      "url": "https://www.factreason.com/mcp"
    }
  },
  "deeplink": "cursor://anysphere.cursor-deeplink/mcp/install?name=factreason&config=eyJ0eXBlIjoiaHR0cCIsInVybCI6Imh0dHBzOi8vd3d3LmZhY3RyZWFzb24uY29tL21jcCJ9"
}

{
  "servers": {
    "factreason": {
      "type": "http",
      "url": "https://www.factreason.com/mcp"
    }
  }
}

{
  "mcpServers": {
    "factreason": {
      "httpUrl": "https://www.factreason.com/mcp"
    }
  }
}

extensions:
  "factreason":
    enabled: true
    name: "factreason"
    type: streamable_http
    uri: "https://www.factreason.com/mcp"
    timeout: 300

Quality 86 / 100good

protocol75 · weight 25

warn
protocol.modernnewest supported version is 2025-06-18; 2026-07-28 not supported, older versions are deprecated until 2027-07-28
n/a
protocol.statelessonly applies to 2026-07-28 servers
pass
protocol.transportstreamable HTTP
n/a
protocol.list_ttlonly applies to 2026-07-28 servers

authorizationn/a · weight 15

n/a
auth.prm, auth.as_metadata, auth.cimdno remote uses OAuth
n/a
auth.secret_in_urlno templated URL

tool hygiene100 · weight 30

pass
tools.descriptionsevery tool has a description
pass
tools.description_lengthdescriptions are concise
pass
tools.schemasevery tool has an object input schema
pass
tools.annotations11 of 11 tools declare readOnlyHint or destructiveHint
pass
tools.directory_hintsevery tool declares readOnlyHint, destructiveHint, idempotentHint and openWorldHint
pass
tools.token_costabout 3,182 tokens to load every tool
pass
tools.api_dumptools are not a one-to-one API dump

stability75 · weight 15

warn
stability.changes11 tool changes in 30 days
pass
stability.rug_pullno tool changed its meaning under the same name

dependenciesn/a · weight 15

n/a
deps.known_vulns, deps.mcp_sdk_version, deps.resolvableno npm or PyPI package

11 tools, about 3,182 tokens to load them all · tool set 7347bdfd823a · tools last changed 2026-10-04 · checked 2026-10-19 22:14 UTC

Tool changes

2026-10-04factreason_subscribe_spec_changeschangedinput schema
2026-10-04factreason_auth_playbookchangedinput schema
2026-10-04factreason_deprecation_scanchangedinput schema
2026-10-04factreason_component_specchangedinput schema
2026-10-04factreason_create_topup_linkchangedinput schema
2026-10-04factreason_create_keychangeddescription
before
Get a FactReason API key for yourself, instantly, with no human, no signup and no card. Returns a key carrying one-off trial credit that you can spend immediately on any tool. CALL THIS FIRST if you have no key, or as soon as any FactReason tool returns HTTP 402 Payment Required — then retry the original call with the key. The tool is free and is never metered. Supplying an email is optional and only affects whether trial credit is granted; a key is always issued either way.
after · 86% of words in common
Get a FactReason API key for yourself, instantly, with no human, no signup and no card. Returns a key carrying one-off trial credit that you can spend immediately on any tool. CALL THIS FIRST if you have no key, or as soon as any FactReason tool returns HTTP 402 Payment Required — then retry the original call with the key, passed as that tool's apiKey argument (or as an Authorization: Bearer header if your client can set one). The tool is free and is never metered. Supplying an email is optional and only affects whether trial credit is granted; a key is always issued either way.
2026-10-04factreason_discover_apichangedinput schema
2026-10-04factreason_integration_briefchangedinput schema
2026-10-04factreason_api_schemachangedinput schema
2026-10-04factreason_api_breaking_changeschangedinput schema

Showing the latest 10. Full history: list_changes · trend: quality JSON.

Checks run on what our credential-free, read-only probes observe; tools are never called and no code audit is performed. How it is computed.

Trust 97 / 100

provenance90

liveness100

freshness100

hygiene100

+repository +namespace-matches-repo +website +reachable +uptime-99% +updated-15d-ago

Derived from observable signals (official registry feed and our own credential-free probes); no code audit performed. How it is computed.

Endpoints

remote	auth	reachable	uptime 30d	p50	protocol	last ok
`https://www.factreason.com/mcp` streamable-http	none	yes	99%	249 ms	2025-06-18	2026-10-19

Tools (11)

`factreason_api_breaking_changes`read-only	Compare two versions of a third-party API and return breaking changes, including removed endpoints, parameter type changes, removed request body fields, and migration guides. Use factreason_package_upgrade_advisory for npm or PyPI packages.
`factreason_api_schema`read-only	Search exact request and response schemas for third-party API endpoints. Pass service alone to list its indexed endpoints, add query to narrow by path or operation, or use query alone across services; returns matches or nearest services. Uses metered access and does not modify source data. Prefer factreason_integration_brief for one callable request.
`factreason_auth_playbook`read-only	Get publisher-declared authentication schemes, scopes, rate-limit headers, and error codes for one third-party API. Returns a structured playbook or nearest service suggestions, and marks undocumented details as unstated rather than guessing. Uses metered access. Prefer factreason_integration_brief when assembling a complete API call.
`factreason_component_spec`read-only	Look up electronics component pin assignments, voltage range, package, and alternatives. Pass exact partNumber for one component or query for a capability search; partNumber takes precedence if both are supplied. For exact lookups, set responseFormat="compact" for tokenizer-measured context savings; the backward-compatible default is "full". Uses metered access and returns matches or suggestions. Confirm critical values against the manufacturer datasheet.
`factreason_create_key`	Get a FactReason API key for yourself, instantly, with no human, no signup and no card. Returns a key carrying one-off trial credit that you can spend immediately on any tool. CALL THIS FIRST if you have no key, or as soon as any FactReason tool returns HTTP 402 Payment Required — then retry the original call with the key, passed as that tool's apiKey argument (or as an Authorization: Bearer header if your client can set one). The tool is free and is never metered. Supplying an email is optional and only affects whether trial credit is granted; a key is always issued either way.
`factreason_create_topup_link`	Create a Stripe Checkout URL for adding prepaid credit to the calling Bearer API key. This creates an external checkout session but does not charge a card. You CANNOT COMPLETE THE PAYMENT YOURSELF, so return the URL to a human, and credit is applied only after they complete payment. Use after HTTP 402 or when balance is low; the tool itself is not metered.
`factreason_deprecation_scan`read-only	Scan publisher specifications for deprecated endpoints or parameters, sunset dates, and replacement operations. Omit filters for the catalogue-wide view, pass service to limit one API, and add endpoints to check selected paths. Uses metered access when findings exist. Use factreason_api_breaking_changes for broader version-to-version changes.
`factreason_discover_api`read-only	Find third-party APIs for a capability when the provider is unknown. Supply a concise capability such as "sms" or "manage DNS"; returns ranked services, example endpoints, and a next step. Uses metered access. When the provider is already known, call factreason_integration_brief instead.
`factreason_integration_brief`read-only	Compile one callable third-party API brief: base URL, auth scheme, required parameters and types, request body, and documented response codes. Service is required and endpoint optionally narrows the operation. Set responseFormat="compact" for tokenizer-measured context savings; the backward-compatible default returns the full brief plus compact form. Uses metered access. Prefer factreason_api_schema when exploring multiple endpoints.
`factreason_package_upgrade_advisory`read-only	Compare two exact published npm or PyPI versions and return publisher-declared registry metadata changes, including yanks, exports, module format, runtime floors, peers, and licences, with before/after evidence. Set responseFormat="compact" for tokenizer-measured context savings; the backward-compatible default is "full". This is a read-only metered lookup; misses are never billed and every API key carries one-off trial credit. Use it for package metadata; use factreason_api_breaking_changes for a third-party HTTP API, and consult changelogs for behavioural changes.
`factreason_subscribe_spec_changes`	Create a persistent specification watch for one service; a Bearer API key is required and each key may hold up to 50 watches. Without webhookUrl, read future events from the polling endpoint; with a public HTTP(S) URL, FactReason sends signed POST callbacks after later spec changes. Duplicate or unsafe webhook registrations are rejected. This does not ingest a specification immediately.

Schemas: list_tools.

Similar MCP servers

Official server.json

{
  "name": "io.github.factreason/factreason",
  "title": "FactReason",
  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
  "remotes": [
    {
      "url": "https://www.factreason.com/mcp",
      "type": "streamable-http"
    }
  ],
  "version": "2.2.0",
  "repository": {
    "url": "https://github.com/factreason/factreason",
    "source": "github"
  },
  "websiteUrl": "https://factreason.com",
  "description": "Check exact npm/PyPI upgrades for evidence-backed breaking changes; query APIs and components."
}