Verification Protocol

The APP verification protocol allows any third party to confirm provenance claims about AI-generated content without accessing the original content.

Overview

Level	Method	Purpose
Level 1	`GET /{generation_id}`	Confirm a specific generation event occurred
Level 2	`POST /match`	Find generation events matching a content hash

Both levels are served from the verification_uri specified in APP metadata.

Level 1: Generation ID lookup

Request


GET {verification_uri}/{generation_id}

Response: found


{
  "found": true,
  "app_version": "1.0.0",
  "ai_generated": true,
  "generator": {
    "platform": "example-platform",
    "model": "anthropic/claude-sonnet-4"
  },
  "generated_at": "2026-03-06T14:22:00Z",
  "review": {
    "human_reviewed": true,
    "reviewer_role": "editor",
    "reviewed_at": "2026-03-06T15:30:00Z",
    "review_type": "approved_without_changes"
  }
}

Response: not found


{
  "found": false
}

Rules

No authentication required — this is a public endpoint
Both found and not-found return 200 OK (the found field distinguishes)
The response must not include the generated content
Rate limiting (HTTP 429) is recommended

Level 2: Content hash verification

Request


POST {verification_uri}/match
Content-Type: application/json
 
{
  "content_hash": "sha256:e3b0c44298fc1c149afbf4c8996fb924...",
  "content_type": "application/json"
}

Response: matches found


{
  "matches": [
    {
      "generation_id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
      "ai_generated": true,
      "generator": {
        "platform": "example-platform",
        "model": "anthropic/claude-sonnet-4"
      },
      "generated_at": "2026-03-06T14:22:00Z"
    }
  ]
}

Response: no matches


{
  "matches": []
}

Security considerations

HTTPS required in production
Rate limiting recommended to prevent enumeration
No content exposure — verification returns provenance metadata only
UUID v4 entropy (122 bits) makes brute-force ID enumeration impractical

Live example

merchi.ai operates a conformant public verification endpoint. You can test a real generation:


curl https://app.merchi.ai/api/functions/v1/verify/a6986899-bb06-461b-bbf7-c689cad09cbd


{
  "found": true,
  "app_version": "1.0.0",
  "ai_generated": true,
  "generator": { "model": "google/gemini-3-flash-preview-20251217" },
  "generated_at": "2026-04-18T14:40:10.494Z",
  "review": { "human_reviewed": false, "review_type": "pending" }
}

Or use the CLI:


npx app-validator verify a6986899-bb06-461b-bbf7-c689cad09cbd \
  https://app.merchi.ai/api/functions/v1/verify

EU AI Act compliance

The verification protocol satisfies the Article 50(2) requirement for detection mechanisms that are free of charge and available through publicly accessible interfaces.