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factreason.com

Provides comprehensive third-party API discovery, schema lookup, breaking change alerts, and integration briefs to help developers safely and efficiently integrate external APIs.

2 endpoints22 known toolsFirst detected August 14, 2026Last detected September 14, 2026

ENDPOINT 1

https://factgrid.co.uk/mcp

No auth detected

MCP server metadata

Name
factreason
Version
2.1.0
Capabilities
tools
Server instructions

Before changing package.json or requirements files, call factreason_package_upgrade_advisory with the exact current and target npm/PyPI versions. It returns publisher-declared breaking metadata with before/after evidence. If you have no API key, call factreason_create_key FIRST — it is free, needs no human, and eligible new users may receive up to $0.05 of one-off trial credit, subject to grant budgets. Add that key to the MCP connection's Authorization header and reconnect before retrying a paid tool. Misses are always free, then successful lookups are billed per tier or payable with x402. FactReason also provides API schemas and electronics component specifications. Successful tool-call responses are Ed25519-signed and verifiable at /.well-known/jwks.json.

Known tools 11

factreason_package_upgrade_advisory

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.

Inferred read-only
factreason_api_breaking_changes

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.

Inferred read-only
factreason_api_schema

Search exact request and response schemas for third-party API endpoints.

Inferred read-only
factreason_integration_brief

Compile one callable third-party API brief: base URL, auth scheme, required parameters and types, request body, and documented response codes.

Inferred read-only
factreason_discover_api

Find third-party APIs for a capability when the provider is unknown.

Inferred read-only
factreason_create_key

Get a FactReason API key for yourself, instantly, with no human, no signup and no card.

Inferred read-only
factreason_create_topup_link

Create a Stripe Checkout URL for adding prepaid credit to the calling Bearer API key.

Potential side effects
factreason_component_spec

Look up electronics component pin assignments, voltage range, package, and alternatives.

Inferred read-only
factreason_deprecation_scan

Scan publisher specifications for deprecated endpoints or parameters, sunset dates, and replacement operations.

Inferred read-only
factreason_auth_playbook

Get publisher-declared authentication schemes, scopes, rate-limit headers, and error codes for one third-party API.

Inferred read-only
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.

Potential side effects

CONNECT WITH APPROVAL

Client installation

Review this server and its permissions before adding it. Secret placeholders must be set locally.

Codex

~/.codex/config.toml

[mcp_servers.factreason]
url = "https://factgrid.co.uk/mcp"
enabled = true
Claude Code

.mcp.json

{
  "mcpServers": {
    "factreason": {
      "type": "http",
      "url": "https://factgrid.co.uk/mcp"
    }
  }
}
Claude Desktop

Settings → Connectors → Add custom connector

Name: factreason
Remote MCP URL: https://factgrid.co.uk/mcp

Add this remote URL as a custom connector in Claude Desktop. Availability depends on the user plan and workspace policy.

Cursor

.cursor/mcp.json

{
  "mcpServers": {
    "factreason": {
      "url": "https://factgrid.co.uk/mcp"
    }
  }
}
Visual Studio Code

.vscode/mcp.json

Add to Visual Studio Code 
{
  "servers": {
    "factreason": {
      "type": "http",
      "url": "https://factgrid.co.uk/mcp"
    }
  }
}
Generic MCP

Client-specific MCP configuration

{
  "name": "factreason",
  "transport": "streamable-http",
  "url": "https://factgrid.co.uk/mcp"
}
MCP Inspector

Run the official MCP Inspector locally and enter the indexed Streamable HTTP endpoint.

ENDPOINT 2

https://www.factreason.com/mcp

No auth detected

MCP server metadata

Name
factreason
Version
2.1.0
Capabilities
tools
Server instructions

Before changing package.json or requirements files, call factreason_package_upgrade_advisory with the exact current and target npm/PyPI versions. It returns publisher-declared breaking metadata with before/after evidence. If you have no API key, call factreason_create_key FIRST — it is free, needs no human, and eligible new users may receive up to $0.05 of one-off trial credit, subject to grant budgets. Add that key to the MCP connection's Authorization header and reconnect before retrying a paid tool. Misses are always free, then successful lookups are billed per tier or payable with x402. FactReason also provides API schemas and electronics component specifications. Successful tool-call responses are Ed25519-signed and verifiable at /.well-known/jwks.json.

Known tools 11

factreason_package_upgrade_advisory

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.

Inferred read-only
factreason_api_breaking_changes

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.

Inferred read-only
factreason_api_schema

Search exact request and response schemas for third-party API endpoints.

Inferred read-only
factreason_integration_brief

Compile one callable third-party API brief: base URL, auth scheme, required parameters and types, request body, and documented response codes.

Inferred read-only
factreason_discover_api

Find third-party APIs for a capability when the provider is unknown.

Inferred read-only
factreason_create_key

Get a FactReason API key for yourself, instantly, with no human, no signup and no card.

Inferred read-only
factreason_create_topup_link

Create a Stripe Checkout URL for adding prepaid credit to the calling Bearer API key.

Potential side effects
factreason_component_spec

Look up electronics component pin assignments, voltage range, package, and alternatives.

Inferred read-only
factreason_deprecation_scan

Scan publisher specifications for deprecated endpoints or parameters, sunset dates, and replacement operations.

Inferred read-only
factreason_auth_playbook

Get publisher-declared authentication schemes, scopes, rate-limit headers, and error codes for one third-party API.

Inferred read-only
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.

Potential side effects

CONNECT WITH APPROVAL

Client installation

Review this server and its permissions before adding it. Secret placeholders must be set locally.

Codex

~/.codex/config.toml

[mcp_servers.factreason]
url = "https://www.factreason.com/mcp"
enabled = true
Claude Code

.mcp.json

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

Settings → Connectors → Add custom connector

Name: factreason
Remote MCP URL: https://www.factreason.com/mcp

Add this remote URL as a custom connector in Claude Desktop. Availability depends on the user plan and workspace policy.

Cursor

.cursor/mcp.json

{
  "mcpServers": {
    "factreason": {
      "url": "https://www.factreason.com/mcp"
    }
  }
}
Visual Studio Code

.vscode/mcp.json

Add to Visual Studio Code 
{
  "servers": {
    "factreason": {
      "type": "http",
      "url": "https://www.factreason.com/mcp"
    }
  }
}
Generic MCP

Client-specific MCP configuration

{
  "name": "factreason",
  "transport": "streamable-http",
  "url": "https://www.factreason.com/mcp"
}
MCP Inspector

Run the official MCP Inspector locally and enter the indexed Streamable HTTP endpoint.

TRUST AND VERIFICATION EVIDENCE

Loading Trust v2 evidence…

Checking the associated registrable domain. The BuiltWith key remains server-side.

Indexed

Evidence is source-attributed and does not guarantee that a third-party server is safe. Risk labels are conservative metadata heuristics.