Validate

Validate cmac of a tag

post

Validates a cmac token for a tag using its UID, counter, and truncated cmac value. Returns tag content and metadata if validation succeeds.

Body

application/json

uidstringRequired

Unique ID of the tag

Example: ABC123TAGUID

ctrstringRequired

Counter used in CMAC generation

Example: 00000045

cmacstringRequired

Truncated CMAC token from the tag

Example: 9f5e6a1c

Responses

200

cmac is valid

application/json

404

Tag not found (invalid UID)

application/json

422

Invalid or outdated cmac

application/json

post

HTTPcURLJavaScriptPython

POST /external/v1/tags/cmac/validate HTTP/1.1
Host: 
Content-Type: application/json
Accept: */*
Content-Length: 57

{
  "uid": "ABC123TAGUID",
  "ctr": "00000045",
  "cmac": "9f5e6a1c"
}

{
  "cmac_verified": true,
  "page_content": {
    "type": null,
    "version": null,
    "data": null,
    "options": {}
  },
  "tag": {
    "uid": "17261BVD8B1816",
    "tamper": null,
    "counter": 48,
    "created_at": "2025-06-01T13:12:44.000Z",
    "updated_at": "2025-06-20T09:42:18.000Z",
    "name": "Sport Mixtape Collection",
    "description": "The 'Speed Anthem Vol. 1' is a custom launch edition of the SportTrack RS-Z designed by CoreStudios and DJ Elan, with exclusive tracks, remixes, and video clips dropping every week.<br/><br/>Tap your tag to start streaming bonus content. [Read more](https://support.example.com/product-guide/sport-mixtape).",
    "image_url": "https://cdn.example.com/images/sport-mixtape-cover.webp",
    "animation_url": null,
    "notes": null,
    "redirect_url": null,
    "template_id": 208,
    "page_content": {
      "type": null,
      "data": null,
      "version": null,
      "options": {}
    },
    "shareable": false,
    "nft_chain_id": 137,
    "nft_contract_address": "0xa8cC9F4501B1d0b19A67E36b7e62C999F2345678",
    "nft_token_id": 492,
    "contract_version": 3,
    "verifications": 31,
    "external_verifications": 7,
    "qc": true,
    "tamper_enabled": false,
    "login_type": 2,
    "header_logo_url": null,
    "builder_io_api_key": "e2d89f4017a346edb9beee1234f8d4d9",
    "builder_io_url": "/b/e2d89f4017a346edb9beee1234f8d4d9/sport-mixtape",
    "tag_view_verifications_count": 29,
    "owner_address": null,
    "email_marketing_consent": null,
    "claim_count": 2,
    "reset_count": 1,
    "page_type": "builder_io",
    "total_tags_count": 492,
    "serial_number": 492,
    "owner_email": null
  }
}