{"version":"v5.0","updated":"2026-10-02","entries":[{"date":"2026-10-02","version":"5.5","changes":["A2A label withdrawn because Headless Oracle does not implement A2A: /.well-known/agent.json is now plain JSON metadata without A2A AgentCard fields, and /.well-known/agent-card.json is no longer served."]},{"date":"2026-03-24","version":"5.4","changes":["Autonomous x402 key minting via on-chain USDC payment","Per-tool MCP telemetry (get_market_status, verify_receipt, list_exchanges)","Per-tool MCP telemetry stored in ORACLE_TELEMETRY KV"]},{"date":"2026-03-22","version":"5.3","changes":["Webhook push notifications for market state changes","Receipt audit log via Supabase (/v5/receipts)","Batch safe_to_execute summary field","Sandbox endpoint for zero-friction testing (/v5/sandbox)"]},{"date":"2026-03-21","version":"5.2","changes":["A2A Agent Card at /.well-known/agent.json","OAuth 2.0 optional upgrade path for MCP (RFC 6749 client_credentials)","MCP metering against plan limits"]},{"date":"2026-03-20","version":"5.1","changes":["x402 micropayments on Base mainnet (USDC, chain 8453)","api.headlessoracle.com subdomain","Plan-based rate limits (builder: 50K/day, pro: 200K/day)"]},{"date":"2026-03-18","version":"5.0","changes":["23 global exchanges (expanded from 7)","Middle Eastern exchange weekends (Fri/Sat for XSAU, XDFM)","Autonomous halt monitor via Polygon.io + Alpaca"]}]}