FactReason
Check exact npm/PyPI upgrades for evidence-backed breaking changes; query APIs and components.
Connect it
Settings → Connectors → Add custom connector
URL: https://www.factreason.com/mcpSettings → Apps & Connectors → Advanced → Developer mode
Create connector with URL: https://www.factreason.com/mcp{
"mcpServers": {
"factreason": {
"url": "https://www.factreason.com/mcp"
}
}
}claude mcp add --transport http factreason https://www.factreason.com/mcp{
"servers": {
"factreason": {
"type": "http",
"url": "https://www.factreason.com/mcp"
}
}
}11 tools, verified live
factreason_package_upgrade_advisoryread-onlyCompare 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 ke
factreason_api_breaking_changesread-onlyCompare 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_schemaread-onlySearch 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_integration_briefread-onlyCompile 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_sche
factreason_discover_apiread-onlyFind 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_create_keyGet 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 heade
factreason_create_topup_linkCreate 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_component_specread-onlyLook 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.
factreason_deprecation_scanread-onlyScan 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_auth_playbookread-onlyGet 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_subscribe_spec_changesCreate 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.
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