openapi: 3.2.0
info:
  title: DELTA Witness — Trust Layer for Autonomous Actions…
  version: 0.7.0
  description: Browser verification and page-state proof for public sources, plus deterministic preflight checks before an autonomous action. DELTA proves observation and change, not truth.
  contact:
    name: DELTA Witness
    email: ruphussten@163.com
    url: https://delta-witness-api.ruphussten.workers.dev/docs
  x-guidance: Call GET /v1/quote before budgeting. Capture preserves a public observation; Guard compares one with deterministic expectations; Guarded-Action Pilot bundles 1-3 public URL proofs for exactly $10. Runtime HTTP 402 payment requirements are authoritative.
servers:
- url: https://delta-witness-api.ruphussten.workers.dev
tags:
- name: preflight autonomous action
paths:
  /v1/preflight:
    post:
      operationId: preflightAutonomousAction
      summary: Preflight a public source before an autonomous action
      description: 'Verify page state before an agent executes a consequential autonomous action. Returns safe/changed/reason/diff plus a proof reference. Current calculated price: $5.'
      tags:
      - preflight autonomous action
      security: []
      x-payment-info:
        price:
          mode: fixed
          currency: USD
          amount: '5'
        protocols:
        - x402: {}
        network: eip155:8453
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              additionalProperties: false
              properties:
                url:
                  type: string
                  pattern: ^https?://
                  description: Public HTTP(S) source to observe before an action.
                prior_proof_id:
                  type: string
                  pattern: ^[0-9a-fA-F-]{36}$
                  description: Optional DELTA proof to use as the hash baseline.
                expected:
                  type: object
                  additionalProperties: false
                  properties:
                    html_sha256:
                      type: string
                      pattern: ^sha256:[0-9a-f]{64}$
                    markdown_sha256:
                      type: string
                      pattern: ^sha256:[0-9a-f]{64}$
                    contains:
                      type: array
                      maxItems: 10
                      items:
                        type: string
                        maxLength: 200
                    excludes:
                      type: array
                      maxItems: 10
                      items:
                        type: string
                        maxLength: 200
                freshness_seconds:
                  type: integer
                  minimum: 0
                  maximum: 2592000
              required:
              - url
      responses:
        '200':
          description: Paid observation delivered
          content:
            application/json:
              schema:
                type: object
                required:
                - ok
                - product
                - proof_id
                - manifest_url
                - public_proof_url
                - bundle_root
                - observed_at
                properties:
                  ok:
                    const: true
                  product:
                    enum:
                    - capture
                    - preflight
                  proof_id:
                    type: string
                    pattern: ^[0-9a-fA-F-]{36}$
                  manifest_url:
                    type: string
                    pattern: ^https?://
                  public_proof_url:
                    type: string
                    pattern: ^https?://
                  bundle_root:
                    type: string
                  observed_at:
                    type: string
                  safe:
                    type:
                    - boolean
                    - 'null'
                  changed:
                    type:
                    - boolean
                    - 'null'
                  reason:
                    type: string
                  diff:
                    type: object
                  idempotent_replay:
                    type: boolean
        '202':
          description: An identical settled fulfillment is already in progress
        '400':
          description: Request rejected
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    type: string
        '402':
          description: x402 v2 payment required or settlement failed
        '409':
          description: Payment replay attempted with a different request
        '413':
          description: Request rejected
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    type: string
        '502':
          description: Settled observation failed; identical retry remains idempotent