sarnai-dev Robots.txt API

openapi: 3.2.0
info:
  title: Agent Output Verifier by SarnAI Robots.txt API
  description: 'Independent verification of AI agent output before you pay: check an AI agent''s JSON against your JSON Schema and business rules (totals, unique IDs). Independent, deterministic checks for invoices, deliverables and any structured output: structure, formats, ranges and cross-field rules, such as "line totals must equal the total," against your own requirements, written in standard JSON Schema plus optional rules. Returns pass/fail, the percentage of checks passed, fix hints, and an Ed25519-signed attestation and receipt that anyone can verify with our public key. Sellers: check your own output before you submit it, and deliver it with a signed attestation and receipt. No signup: pay per call with x402 v2, in USDC on Base or Solana. 1,000 free checks a day per caller, then $0.02 per check (x402, USDC on Base or Solana). AI Agent Scores: $0.01 per lookup when there is a score; a lookup for an AI agent with no history is answered free, signed. `POST /verify/schema` (also offered as `POST /verify/deliverable`: the same check, shape, signed attestation and receipt, price and networks) is $0.02 USDC per call and `GET /score/{agent_id}` is $0.01 USDC per call, both paid via x402 in USDC on Base or Solana (an unpaid request gets HTTP 402, which lists the options in the `Payment-Required` response header; a paid request''s signed payment rides in the `Payment-Signature` request header, and a settled response''s settlement receipt rides in the `Payment-Response` response header). A `fail` result is a complete, valid answer and is charged the same as a `pass`. **Payment errors:** every 402 body is a structured `payment_error` - a stable `error_code` (`no_payment`, `malformed_payment`, `unsupported_payment_version`, `no_matching_requirements`, `amount_mismatch`, `recipient_mismatch`, `invalid_signature`, `expired_authorization`, `payment_already_used`, `insufficient_funds`, `facilitator_unreachable`, `facilitator_error`), a clean `message`, `charged: false`, `retryable`/`retry_after`, the current `payment_terms`, and `next_actions` - identical on REST and in MCP''s `structuredContent.payment_error`. See the 402 response below for what each code means. **Free verification:** 1,000 free checks a day per caller, then $0.02 per check (x402, USDC on Base or Solana). One counter is shared by the MCP tool `verify_schema` (`POST /mcp`) and the REST routes `POST /verify/schema` and `POST /verify/deliverable`, where a valid unpaid request is served free and says what is left in the `Free-Allowance-Remaining`, `Free-Allowance-Limit` and `Free-Allowance-Resets` response headers. An unpaid request that needs payment gets a 402 whose body reports this caller''s own remaining free allowance. **AI Agent Scores:** `GET /score/{agent_id}` and the MCP tool `get_verification_record` are $0.01 per lookup when there is a score, with no free allowance; a lookup for an AI agent with no history (or a reserved `test-` id) is answered free, signed, with `reason: no_data`, on REST and through the MCP tool. **Errors:** every error other than a payment error has one shape (`code`, `message`, `status`, `retryable`, `charged`, `next_actions`; validation errors add a `fields` list naming each bad field and how to fix it), on REST and in MCP tool results, and the caller''s input is never echoed. An invalid request is rejected with 422 before anything is verified or settled; an unpaid request to a paid route always gets the 402 challenge, an empty or invalid one with `request_problems`, and GET/HEAD on the verify routes get the same challenge. Every error response (4xx and 5xx, every route) carries a `guidance` block: what to do, a minimal valid example, the price and how to pay, the free-allowance note and the llms.txt link; a 5xx also says nothing was charged and when to retry. The live free-allowance numbers are stated in one place, the "Free allowance" section of `/llms.txt`.'
  version: 0.5.8
tags:
- name: Robots.txt
paths:
  /robots.txt:
    get:
      summary: Robots Txt
      description: Everything is allowed; the sitemap line names the host the crawler asked (app.api.routes.discovery_files).
      operationId: robots_txt_robots_txt_head
      responses:
        '200':
          description: Successful Response
          content:
            text/plain:
              schema:
                type: string
      tags:
      - Robots.txt
    head:
      summary: Robots Txt
      description: Everything is allowed; the sitemap line names the host the crawler asked (app.api.routes.discovery_files).
      operationId: headRobotsTxt
      responses:
        '200':
          description: Successful Response
          content:
            text/plain:
              schema:
                type: string
      tags:
      - Robots.txt
      x-operation-id-source: normalized
      x-operation-id-original: robots_txt_robots_txt_head