Last updated: 2026-04-08
Base URL: https://headlessoracle.com
All responses include security headers (HSTS, CSP, X-Content-Type-Options, X-Frame-Options, Referrer-Policy, Permissions-Policy). JSON responses use Content-Type: application/json; charset=utf-8.
Signed receipt in demo mode. Same 4-tier fail-closed as live, but receipt_mode: "demo".
Next open/close times in UTC. Includes lunch_break, settlement_window, data_coverage_years.
Directory of all 28 supported exchanges with MIC, name, timezone, hours, mic_type.
Public key registry with canonical_payload_spec, valid_from, valid_until.
Signed liveness probe. Returns { status: "OK", source: "SYSTEM", signature }. On signing failure: 500 CRITICAL_FAILURE.
Daily market intelligence snapshot: open/closed markets, lunch breaks, upcoming events, DST transitions.
Instant sandbox key (200 calls, 7-day TTL). No signup required. IP rate-limited.
JSON pricing tiers (sandbox, free, x402, credits, builder, pro, protocol).
Live metrics snapshot for investor/partner check-ins.
Social proof: exchange count, uptime, test count, evaluator scores, status codes.
OpenAPI 3.1 specification covering all endpoints.
MCP Streamable HTTP endpoint. See MCP Reference.
Signed receipt in live mode. Also supports free trial (3/day/IP) and x402 payment when no key provided.
Headers: X-Oracle-Key: {api_key}
Response headers: X-Oracle-Plan, X-RateLimit-Limit, X-RateLimit-Remaining, X-RateLimit-Reset, X-Attestation-Mode
Batch signed receipts. All MICs validated up front. Independent signing per MIC. Includes summary.safe_to_execute.
Per-key usage stats, limits, credit balance, plan details.
Audit log query (builder+ plans only). Supports limit, mic, from params.
Register webhook for market state changes. Plan limits: builder=5, pro=25.
Paddle transaction (subscription or credits). Query param type=credits for one-time credit pack.
Paddle webhook handler. Events: transaction.completed, subscription.updated, subscription.past_due, subscription.canceled.
Mint persistent API key via on-chain USDC payment. Builder: 99 USDC, Pro: 299 USDC.
Buy credits via x402 micropayment.
| Path | Format | Purpose |
|---|---|---|
/llms.txt |
Text | LLM crawler index |
/llms-full.txt |
Text | Comprehensive LLM docs |
/AGENTS.md |
Markdown | AAIF agent briefing |
/SKILL.md |
Markdown | Ampersend skill format |
/.well-known/agent.json |
JSON | A2A Agent Card |
/.well-known/mcp/server-card.json |
JSON | MCP server metadata |
/.well-known/x402.json |
JSON | x402 payment discovery |
/.well-known/oracle-keys.json |
JSON | RFC 8615 key discovery |
/.well-known/oauth-authorization-server |
JSON | RFC 8414 AS metadata |
All errors return JSON with error (SCREAMING_SNAKE_CASE code), message, and docs fields. HTTP status codes are deterministic:
- 400: Invalid request (bad MIC, missing params)
- 401: Missing or invalid API key
- 402: Payment required (suspended key, trial exhausted)
- 403: Forbidden (key not found)
- 405: Method not allowed
- 429: Rate limited
- 500: Critical failure (signing offline)
| Plan | Daily Limit |
|---|---|
| Free trial | 3/day per IP |
| Free tier | 500/day |
| Sandbox | 200 calls total (7-day key) |
| Credits | Per balance |
| Builder | 50,000/day |
| Pro | 200,000/day |
| Protocol | Unlimited |