{
      "tool_id": "art-121-document-integrity-anchor",
      "tool_version": "1.0.0",
      "display_name": "Document Integrity & eIDAS Electronic Timestamp Anchor",
      "mcp_name": "anchor_document_integrity",
      "mandate_type": "compliance_mandate",
      "wave": 22,
      "gpu": false,
      "url": "https://ainumbers.co/chaingraph/art-121-document-integrity-anchor.html",
      "description": "Bind a document SHA-256 and claimed timestamp into an OCG execution_hash that serves as an eIDAS Art.41 / RFC 3161-aligned electronic timestamp: self-verifiable, no external TSA call. Optional C2PA manifest field. Feeds timestamp attestation verifier (art-122).",
      "input_schema_ref": "chaingraph/art-121-document-integrity-anchor.html#manifest",
      "consumes": [],
      "feeds": [
        "art-122-timestamp-attestation-verifier"
      ],
      "status": "live",
      "conformance_fixtures": true,
      "compute_capability": "server",
      "compute_images": [{"system":"sha256-source","image_id":"sha256:7f6d0e49c1eeb8c26e4d0453f504f575f36b4547315236e2d5796bea05076cb0","valid_from":"2026-07-10"},{"system":"risc0","image_id":"sha256:a1a0bc89b5b1febaeda3519f6dbade0fa5ac16beeb143c4e1b01689573567bc6","valid_from":"2026-06-28"}],
      "compute_proof": {
        "type": "ZkVmReceipt",
        "system": "risc0",
        "receiptFormat": "groth16-bn254",
        "imageId": "sha256:a1a0bc89b5b1febaeda3519f6dbade0fa5ac16beeb143c4e1b01689573567bc6",
        "seal": "Ard0At9EHK6xBnW2nt2Ku83Z7FLD1KfP1421oxIrqiMsQjxlSNFzE9T9NvEzIex5FE1ltJZ86yHjxAkIAg1ZRwrFJWK3aJaWyO9OB9R8751mw7eTbj11geSVmXbYsXGkBKFsifvKXmZuWWbKckovbtt6OZXvpe7xccMPyCkIFcwLwz/gxdMx2z7MiF7FpFCERUyk2HS3Hzisl3PxANWDZicWaiY2Q3GkK8I7m9+VQFXyO3Lb1bIRyc15aVq4NinlFDbmR4/IGUjZddZS4TvrfD7+UO5iactpFKtDHW1G8R4CbiPclxg7K9aa63MLMhtsQTIXen7bXh6BnU8GPAQO1w==",
        "journal": {
          "chaingraph_version": "0.4.0",
          "kernel_digest": "sha256:ed284c7e429fc0c4d207033d714e8b5cc4d59bc8f960684f248ba01a849fba99",
          "output": {
            "anchored": true,
            "document_hash": "sha256:abcdef1234567890abcdef1234567890abcdef1234567890abcdef1234567890",
            "document_type": "contract",
            "timestamp_claim": {
              "algorithm": "sha256",
              "standard": "eIDAS Art.41 / RFC 3161-aligned",
              "timestamp": "2026-06-25T10:00:00Z"
            }
          }
        }
      }
    }