How we rate
Score = 0.45·availability + 0.20·price integrity + 0.15·latency +
0.10·protocol quality + 0.10·consistency. Availability enters as the 95% Wilson
lower bound of the measured valid share, cubed: an agent-facing service that answers
only 75% of probes is close to useless, and a perfect day on thin evidence can't outrank a
proven week. Availability is our hourly probe success rate, not a guarantee of uptime
between probes.
Dynamic pricing (oracle-pegged, ≥5 observed changes) is never punished per probe;
we compare the catalog price to the median live price instead. A persistent gap
between the advertised price and the live price we observe collapses the price score toward zero.
Every domain is probed with its declared method and schema, one request per run,
never with destructive methods. No payments are made yet, so we verify that a service
returns a valid payment challenge, not that it delivers correct content after payment;
paid output verification is the next stage.
Coverage. Our universe is the public x402 catalog (Coinbase's CDP Bazaar
discovery API). A service not listed there is not graded — it is simply not yet
visible to us. "Every service" means every service in that catalog, not every x402
endpoint that exists.
Not rated
189 provisional (fewer than 60 probes, typically new listings)
41 unratable (no valid 402 in the whole window)
5 broken metering (returned content with HTTP 200 and no 402 challenge on our probes; may be free, moved, or a probing artifact)
Independence: who pays for this
Rated parties never pay us, and never will. That rule is the product: a rating
you can pay for is worth nothing to the buyer. Today the probing is self-funded:
the unpaid probes cost close to nothing and run on our own hardware. If this becomes a business,
revenue comes from the buyer side only: paid score lookups for agents and routing
referrals. Never from the services being rated.
Methodology, weights and raw definitions are public.
*Call volume is the catalog's own popularity metric, shown for contrast; its
tie-corrected rank correlation with our quality score is a weak 0.05. It is not an input.
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