Free tools

Three public services, each useful on its own and free to use without an Axiom account. They are also entry points: a receiving organisation can check an agent, follow a tool release or verify a receipt even when the other party has no Sectigo account.

Tool	First useful result	Where
Agent identity check	Issuer, claimed operator, domain control, legal entity, key status and when each was checked.	sectigoaxiom.com/tools/identity-check, POST /v1/public/identity-check
MCP tool and skill change monitor	A release history for a public MCP server, SKILL.md or npm package, and a diff between releases.	sectigoaxiom.com/tools/change-monitor, POST /v1/public/monitors
Receipt verifier	Each signer, the disclosed fields, missing claims and which phases a receipt proves.	sectigoaxiom.com/tools/verify-receipt, axiom verify, GET /v1/public/fixtures

The API endpoints live on https://api.sectigoaxiom.com. They need no authentication; each is rate-limited per client address (for example 30 identity checks and 10 new monitors per minute) and answers 429 rate_limited with retry_after_seconds beyond that. Outbound fetches (cards, MCP servers, skills, registries) go through an SSRF policy that refuses private and internal addresses.

What each tool does not do matters as much as what it does: the identity check reports assertions, it does not grant access; the change monitor compares declarations, not behaviour; the verifier proves what was signed, and trusts only the keys you tell it to.