WritersLogic Verifiable AI Agent Hub

WritersLogic Verifiable AI Agent Hub Steganography API

Zero-width character watermark signing and verification

Documentation GitHub OpenAPI

Operations 2

POST /v1/stego/sign Generate watermark parameters #

POST /v1/stego/verify Verify watermark #

Specifications

⚙

OpenAPI

https://artifacts.apis.io/writerslogic-com/openapi/writerslogic-com-steganography-api-openapi.yml

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OpenAPI Specification

openapi: 3.2.0
info:
  title: WritersProof Steganography API
  version: 1.0.0
  description: Certificate Authority and verification API for the Proof-of-Effort protocol. Certify, verify, and prove human authorship.
  contact:
    name: WritersLogic LLC
    url: https://writersproof.com
  license:
    name: SSPL-1.0
    url: https://www.mongodb.com/licensing/server-side-public-license
servers:
- url: https://api.writersproof.com
  description: Production
- url: https://api.writerslogic.com
  description: Legacy
tags:
- name: Steganography
  description: Zero-width character watermark signing and verification
paths:
  /v1/stego/sign:
    post:
      tags:
      - Steganography
      operationId: stegoSign
      summary: Generate watermark parameters
      description: Generate zero-width character (ZWC) watermark parameters for a completed session. Returns watermark bits, embedding seed, and HMAC tag.
      security:
      - bearerAuth: []
      - apiKeyAuth: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - sessionId
              - documentHash
              properties:
                sessionId:
                  type: string
                  format: uuid
                documentHash:
                  type: string
                  pattern: ^[0-9a-fA-F]{64}$
      responses:
        '201':
          description: Watermark parameters generated
          content:
            application/json:
              schema:
                type: object
                properties:
                  watermarkBits:
                    type: string
                    description: 16 hex chars (64 bits)
                  embeddingSeed:
                    type: string
                    description: SHA-256 hex for position determination
                  zwcCount:
                    type: integer
                    example: 32
                  hmacTag:
                    type: string
                    description: Full HMAC-SHA256 hex tag
        '400':
          $ref: '#/components/responses/ValidationError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '409':
          description: Session must be completed before watermarking
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
  /v1/stego/verify:
    post:
      tags:
      - Steganography
      operationId: stegoVerify
      summary: Verify watermark
      description: Verify an extracted ZWC watermark against stored watermark records using constant-time comparison.
      security:
      - bearerAuth: []
      - apiKeyAuth: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - documentHash
              - extractedTag
              properties:
                documentHash:
                  type: string
                  pattern: ^[0-9a-fA-F]{64}$
                extractedTag:
                  type: string
                  pattern: ^[0-9a-fA-F]+$
      responses:
        '200':
          description: Watermark verification result
          content:
            application/json:
              schema:
                type: object
                properties:
                  valid:
                    type: boolean
                  zwcFound:
                    type: integer
                  zwcExpected:
                    type: integer
                    example: 32
                  documentHash:
                    type: string
        '400':
          $ref: '#/components/responses/ValidationError'
        '401':
          $ref: '#/components/responses/Unauthorized'
components:
  responses:
    Unauthorized:
      description: Authentication required
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    NotFound:
      description: Resource not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    ValidationError:
      description: Request validation failed
      content:
        application/json:
          schema:
            type: object
            properties:
              error:
                type: string
                example: Validation failed
              details:
                type: array
                items:
                  type: string
  schemas:
    Error:
      type: object
      properties:
        error:
          type: string
      required:
      - error
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: Supabase JWT token
    apiKeyAuth:
      type: apiKey
      in: header
      name: X-API-Key
      description: API key with wp_sk_ prefix