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Registered sites answer every agent that asks: who runs this, what it declares, verified by a fetch. Free.

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Free tools · what an agent is told

No record yet for constructor.io

CrawlCheck holds no record for this domain; nothing is guessed. That is exactly what an agent is told: status: not_measured, no decision, no score, no guess. Scan it now and the next agent that asks gets a measured answer.

Scan constructor.io now, free →

Read it as an agent

The same answer, as calls

Everything on this page is a field of one signed body. An agent reads the body; a person reads this.

The signed answerGET /api/v1/resolve?domain=constructor.ioJSON, Ed25519-signed, public, no key Before actingPOST /api/v1/preflight {domain, action}allow, warn, require_confirmation or block for one action Its evidencethe registry rowevery row re-derives from a fetch Verify itnode crawlcheck-verify.mjs --online answer.jsonhash, signature and signing policy, against the keys CrawlCheck publishes