ExchangeRebel Payability API

openapi: 3.2.0
info:
  title: ExchangeRebel — pay-per-call APIs for AI agents (x402 on…
  version: 1.0.0
  contact:
    name: 'ExchangeRebel (operator: Rebel Data)'
    url: https://exchangerebel.com
    email: sound.money.investing@gmail.com
  x-guidance: 'All paid operations use x402 on Solana: call without payment to get a 402 challenge (SOL recipient + USDC token account + fresh memo), pay with the memo attached via the Solana Memo program, then retry with header X-Payment-Tx: <signature> and ?toll_memo=<memo>. Challenges are dual-version: the PAYMENT-REQUIRED header carries the x402 v2 PaymentRequired object and the response body carries the same challenge in x402 v1 form for compatibility. Free operations (security: []) include each service''s /health catalog with full response shapes. Prices in x-payment-info are USD per call unless the summary says otherwise (RPC is per 1,000-request block; Telegram provisioning is per bot-month; transcription is per minute of audio).'
  description: '67 data and utility APIs behind x402 tolls, settled in SOL or USDC on Solana. Call a paid endpoint without payment to receive a 402 x402 challenge (recipient + fresh memo), pay with the memo attached via the Solana Memo program, then retry with the X-Payment-Tx header and toll_memo query parameter. Free catalog/health endpoints are marked without x-payment-info. Full catalogs: GET /toll/discovery and each service''s /health.'
servers:
- url: https://exchangerebel.com
tags:
- name: Payability
paths:
  /toll/payability:
    get:
      tags:
      - Payability
      summary: Payability Verdict service catalog
      responses:
        '200':
          description: 'Success. Returns the service catalog: what the payability verdict and memo-binding check include, the prices ($0.01 per endpoint each), the published criteria (payability/v1), the pinned test corpus, and the scope statement (a deterministic challenge payability verdict: this service fetches one named endpoint''s live 402 challenge exactly as an unauthenticated stranger would, decodes the challenge body and the PAYMENT-REQUIRED header, and grades the fields; the memo op grades the challenge side only over two back-to-back fetches; no composite score is computed and no model is called).'
      security: []
      operationId: getTollPayability
      x-operation-id-source: derived
  /toll/payability/health:
    get:
      tags:
      - Payability
      summary: Payability Verdict service health
      responses:
        '200':
          description: Success. Returns service liveness and the report signer address.
      security: []
      operationId: getTollPayabilityHealth
      x-operation-id-source: derived
  /toll/payability/criteria:
    get:
      tags:
      - Payability
      summary: The published payability verdict criteria
      responses:
        '200':
          description: 'Success. Returns the full published criteria (payability/v1): the input contract and target-URL policy, the six payability states and five memo-binding states, every field-check factor, the scope block, and the pinned public test corpus identity; every report is reproducible from them.'
      security: []
      operationId: getTollPayabilityCriteria
      x-operation-id-source: derived
  /toll/payability/corpus:
    get:
      tags:
      - Payability
      summary: The pinned public test corpus identity
      responses:
        '200':
          description: 'Success. Returns the public test corpus identity for payability/v1: corpus id payability-corpus/v1 and its SHA-256 pin 3b2821f40815b77a85da6ac7c00cf2cc5d5c94a4aa166b40ccad1fd331c12427 (the SHA-256 of the corpus''s canonical serialization, verifiable with the published harness). The corpus is buyer-runnable before paying.'
      security: []
      operationId: getTollPayabilityCorpus
      x-operation-id-source: derived
  /toll/payability/precheck:
    post:
      tags:
      - Payability
      summary: Free headline payability pre-check of one endpoint URL
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                caller:
                  type: string
                  description: Solana base58 wallet of the operator; keys the free allowance (100/day per wallet).
                url:
                  type: string
                  description: The one endpoint URL to grade. Fetched once at check time (twice, back to back, for the memo op) and never stored.
                op:
                  type: string
                  description: 'Optional op selection for the pre-check: ''check'' (default) or ''memo''.'
              required:
              - caller
              - url
      responses:
        '200':
          description: 'Success. Returns the headline only: the submitted URL validated against the published target-URL policy. No fetch is performed and no verdict is returned. When the caller''s free allowance is exhausted, the response is the /toll/payability/check payment challenge instead.'
      security: []
      operationId: postTollPayabilityPrecheck
      x-operation-id-source: derived
  /toll/payability/check:
    post:
      tags:
      - Payability
      summary: Full signed payability verdict for one named endpoint
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                url:
                  type: string
                  description: The one endpoint URL to grade. Fetched once at check time (twice, back to back, for the memo op) and never stored.
              required:
              - url
      responses:
        '200':
          description: 'Success. Returns the full signed report: the verdict state (POPULATED, AMOUNTS-ONLY, UNCONFIGURED, HEADER-MISSING, RESOURCE-MISMATCH, or NOT-A-402), every field-check factor, and an as-of timestamp. The named endpoint''s challenge is fetched once, at check time, and is never stored.'
        '402':
          description: 'Payment Required (x402). A per-item fee: $0.01 per endpoint - each endpoint URL you submit is charged at $0.01; the payment includes one endpoint payability verdict — this service fetches that one endpoint''s live 402 challenge exactly as an unauthenticated stranger would, decodes the challenge body and the PAYMENT-REQUIRED header, and returns one signed report giving the verdict state (POPULATED, AMOUNTS-ONLY, UNCONFIGURED, HEADER-MISSING, RESOURCE-MISMATCH, or NOT-A-402), every field-check factor (recipient present, token account present, memo present, amounts present and mutually consistent, resource.url equal to the called URL, header-to-body equality for memo, amount and payTo, and the description-length risk flag), and an as-of timestamp. No composite score is computed. A free pre-check validates the submitted URL against the published target-URL policy only — it does not fetch the endpoint and returns no verdict. The target endpoint''s challenge is fetched once, at check time, and is never stored; the payments ledger records only the payer, the time, the price, the verdict state, and the verdict line. The response body carries the payment instructions in x402 v1 form: payTo (the operator''s Solana wallet), the amount (10000 USDC units = $0.01 per endpoint) and a fresh memo. Pay in USDC on Solana with the memo attached via the Solana Memo program, then resubmit the same request with the payment transaction in the X-Payment-Tx header and ?toll_memo=<memo>, re-sending the URL in the request body. The PAYMENT-REQUIRED response header carries the same object in x402 v2 form.'
      x-payment-info:
        protocols:
        - x402
        price:
          mode: fixed
          currency: USD
          amount: '0.01'
      security:
      - x402Payment: []
      operationId: postTollPayabilityCheck
      x-operation-id-source: derived
  /toll/payability/memo:
    post:
      tags:
      - Payability
      summary: Full signed memo-binding check for one named endpoint
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                url:
                  type: string
                  description: The one endpoint URL to grade. Fetched once at check time (twice, back to back, for the memo op) and never stored.
              required:
              - url
      responses:
        '200':
          description: 'Success. Returns the full signed report: the memo-binding verdict state (BOUND, MEMO-REUSED, LEG-MISMATCH, MEMO-ABSENT, or NOT-A-402), every factor over two back-to-back fetches, and an as-of timestamp. Challenge side only - the seller''s replay store is never implied checked.'
        '402':
          description: 'Payment Required (x402). A per-item fee: $0.01 per endpoint - each endpoint URL you submit is charged at $0.01; the payment includes two back-to-back fetches of the named endpoint''s live 402 challenge, memo presence grading per leg (body and PAYMENT-REQUIRED header) in each fetch, memo uniqueness grading across the pair, freshness-format grading of the memo (regenerated vs static, plus its structural format class), header-to-body memo equality in each fetch, and the correlation-field census (the NAMES only, never values, of the correlation-capable fields the challenge carries, per leg per fetch) — returned as one signed report giving the memo-binding verdict state (BOUND, MEMO-REUSED, LEG-MISMATCH, MEMO-ABSENT, or NOT-A-402), every factor, and an as-of timestamp. No composite score is computed. This op grades the CHALLENGE SIDE only: the seller''s seen-set / replay store is internal and unobservable and is never implied checked. A free pre-check (op memo) validates the submitted URL against the published target-URL policy only — it does not fetch the endpoint and returns no verdict. The endpoint''s challenges are fetched at check time and are never stored; the payments ledger records only the payer, the time, the price, the memo-binding state, and the verdict line — never any memo value. The response body carries the payment instructions in x402 v1 form: payTo (the operator''s Solana wallet), the amount (10000 USDC units = $0.01 per endpoint) and a fresh memo. Pay in USDC on Solana with the memo attached via the Solana Memo program, then resubmit the same request with the payment transaction in the X-Payment-Tx header and ?toll_memo=<memo>, re-sending the URL in the request body. The PAYMENT-REQUIRED response header carries the same object in x402 v2 form.'
      x-payment-info:
        protocols:
        - x402
        price:
          mode: fixed
          currency: USD
          amount: '0.01'
      security:
      - x402Payment: []
      operationId: postTollPayabilityMemo
      x-operation-id-source: derived
  /toll/payability/metrics:
    get:
      tags:
      - Payability
      summary: Payability Verdict aggregate counters
      responses:
        '200':
          description: Success. Returns aggregate counters (paid checks, paid memo checks, distinct payers, free pre-checks today). Aggregate only - no payer identities, no submitted endpoint content.
      security: []
      operationId: getTollPayabilityMetrics
      x-operation-id-source: derived
components:
  securitySchemes:
    x402Payment:
      type: apiKey
      in: header
      name: X-Payment-Tx
      description: 'x402 toll payment proof: the Solana transaction signature of a payment carrying the memo from the 402 challenge; send together with ?toll_memo=<memo>. Payment itself is made on-chain in SOL or USDC to the recipient named in the challenge.'