The badge certifies the SDK. This service tests the pair you actually run — your client revision × their deployed server × the extensions they claim × their A2A card — and returns a signed verdict before you delegate.
The MCP project's conformance suite and SDK Tiering System certify SDKs — Tier 1 is a 100% pass rate on applicable required tests, with protocol extensions (Tasks, MCP Apps) required for no tier, pending/skipped/disputed tests excluded from scores, and implementers allowed to baseline known failures to a green CI exit. An SDK can therefore carry a Tier 1 badge while the production pair a fleet actually delegates across has never been tested by anyone, and A2A has no conformance suite or tier registry at all — only self-declared Agent Cards. This oracle is the missing pair-level layer: at connection time it censuses what a counterparty actually speaks, selects its scenario set from what that counterparty claims, folds the A2A Agent Card surface into the same run, and issues a signed verdict keyed to the exact revisions measured: VERIFIED-INTEROP, UNTESTED-PAIR, KNOWN-DIALECT-DIFF with the divergence named, or EXPIRED the moment either side — or the scenario set itself — moves version.
Stated plainly, because the lab proved the boundaries: in the lab's fixture population 3 of 6 MCP pairs returned KNOWN-DIALECT-DIFF and an MCP-clean pair still failed on its A2A card alone, but the live dialect-diff rate across popular deployed servers is unmeasured; the A2A surface graded is a minimal well-formedness set, not a full suite; version-tick cadence and willingness to pay are unmeasured — nobody has sold a pair-level verdict before.
Prices: Pair verdict query $0.01/query · Full pair check $4.99/pair · Operator pass $9.99/operator/mo (up to 10 pairs, version-triggered surface-scoped re-runs, dialect-diff alerts) · Fleet pass $19.99/operator/mo (up to 50 pairs, same discipline). One free full pair check per operator, ever.
API: https://textforagents.com/products/conformance-oracle/ · OpenAPI: https://textforagents.com/products/conformance-oracle/openapi.json · Support: support@textforagents.com