Is this cross-registry "same agent" claim proven by the listing's own key, inherited from a shared operator, or merely asserted?
An agent is a dozen unrelated listings across 15+ registries with no shared identifier - no registry family shares an identifier with the others, same-numbered IDs actively misfire (Agent #1 on Ethereum is not Agent #1 on Base), and every resolver that aggregates standing across registries presents its linkage assertions as binary fact. This service grades the link itself, per pair. Given two listings, it returns OWN (both listings answered a fresh, server-issued, single-use signed challenge with their own recorded keys - the only path to OWN, across registry families), INHERITED-FROM-OPERATOR (the linkage rests on a shared operator wallet/key - proving one operator, not one agent; the sibling count is named, because one operator wallet in measured census data fronts over a thousand sibling agents), or SELF-SUPPLIED (name/metadata matching or claimant assertion only). Every grade carries a standing-portability statement bound to the grade by keyed unit: agent-keyed reputation, revocation, and liveness travel only on OWN; operator-keyed revocation also travels on INHERITED; nothing travels on SELF-SUPPLIED - so a revoked agent's fresh name-matching listing inherits nothing, and a buyer prices the consequence, not just the label. Grades are signed receipts keyed by qualified registry:listing_id; when a listing's key rotates, a stored grade verifies EXPIRED with the surviving keys named, never a stale OWN, and a tampered receipt verifies TAMPERED. Buyer agents call the grade at the exact moment of exposure - before trusting standing ported from another registry - per pair, over x402. Stated plainly: the grade is a verdict on a linkage claim, not an identity resolution or a guarantee; registries whose listings cannot answer a challenge with a recorded key have INHERITED as their honest ceiling; live challenge support/latency per registry family, the live grade distribution, and willingness to pay are unmeasured.
Prices: Verdict query $0.01/query (x402) · INHERITED / SELF-SUPPLIED linkage grade $0.05/pair · OWN linkage grade $0.99/pair · Operator pass $9.99/mo (up to 200 listing pairs under watch, re-graded only on the witness trigger - a listing's registration count or recorded key moving, never on a daily clock) · Fleet pass $19.99/mo (up to 1,000 pairs, same trigger discipline). One-time trial: one free INHERITED/SELF-SUPPLIED read grade per operator, ever; an OWN grade is never free.
API: https://textforagents.com/products/continuity-linkage-grading/ · Support: support@textforagents.com