{"uid":"cap_FLpXnBt1LPlCH2fN8kL-G","slug":"council-of-ai-a2a-agent-population-slice-4facb269","name":"Council of AI — A2A Agent Population Slice","description":"We measure how AI systems behave against frozen, published tests and publish checkable evidence. Issued measurement cards are signed; unsigned supporting runs are labelled. 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The signature field may be null for unsigned supporting runs.","failureModes":["Payment not included or invalid: returns HTTP 402 requiring x402 USDC payment","Invalid method (POST, PUT, etc.): schema only accepts GET, HEAD, DELETE","Data not yet indexed: state field may reflect non-INDEXED status","Attestation signature null: unsigned supporting runs are labelled as such, not a hard error","Network or provider downtime: standard HTTP 5xx response"],"whenToPreferThis":"Choose this endpoint when you need a cryptographically signed, independently verifiable snapshot of the A2A agent population with checkable evidence — particularly for governance audits, compliance reporting, or cross-verification of agent registry claims. Prefer this over raw registry scrapes when attestation and tamper-evidence matter. Not suitable for real-time streaming or querying individual agent details.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-02T02:15:39.731Z","isFirstParty":false,"canonicalSlug":"council-of-ai-a2a-agent-population-slice-4facb269"}