API response drift
Catch status, content-type, missing-field, forbidden-field, type, and invariant-value drift against an explicit response contract.
View schemaJustHandled Labs
Evidence for the seams where agents break.
Three deterministic checks turn supplied operational records into structured findings and versioned receipts. Each costs $0.05 USDC per run on Base mainnet. Discovery, schemas, and sample inputs are free.
Webhook replay
Check declared events, versions, payload fields, signature evidence, deterministic freshness, idempotency, and repeated deliveries.
View schemaPolicy changes
Build clause-level evidence for additions, removals, text, applicability, and requirement changes with version guardrails.
View schemaCall POST /api/run/:utility through an x402-capable client or use @justhandledlabs/agent-client over CLI or MCP. Most products analyze supplied evidence. The Chicago permit packet alone uses a bounded owned read-only adapter; no product accepts an arbitrary fetch URL. The gateway does not authenticate webhook signatures or provide legal advice.
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