OpenChainGraph Suite · wave 22 · compliance_mandate

Document Integrity & Timestamp Anchor

Note (dated 2026-08-04): a chain composes independent computations performed in an analytical order. No step's output is carried into the next step by the execution model; each step computes from its own declared inputs. This is true of every chain on this site, including chains whose per-step copy below reads as a data handoff.

Anchor document SHA-256 + claimed timestamp as an eIDAS Art.41-aligned electronic timestamp (art-121) → verify that the anchor recomputes correctly and all claims are internally consistent (art-122). W3C VC export via §13.11.

OpenChainGraph · 2 Steps compliance mandate eIDAS Art.41 · RFC 3161 W3C VC §13.11 Hash-Anchored §4 chain_depth:2 · Zero PII
Chain Topology — Document Integrity & Timestamp Anchor
art-121 Document Integrity Anchor art-122 Timestamp Attestation Verifier ⊣
§4 Execution Hash · Chain Definition Anchor
execution_hash:computing…
Chain Stages · 2 Steps
1ROOT · D0node
Document Integrity & eIDAS Electronic Timestamp Anchor art-121
Document hash + timestamp anchor feeds attestation verification
MCP Call · anchor_document_integrity
{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "anchor_document_integrity",
    "arguments": {
      "document_hash": "sha256:abcdef1234567890abcdef1234567890abcdef1234567890abcdef1234567890",
      "claimed_timestamp": "2026-06-25T10:00:00Z",
      "hash_algorithm": "sha256",
      "document_type": "contract"
    }
  },
  "id": 1
}
https://mcp.ainumbers.co/mcp
↓
2TERMINAL · D1node
Timestamp Attestation Verifier art-122
Exports verified timestamp artifact with execution_hash — final stage
MCP Call · verify_timestamp_attestation
{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "verify_timestamp_attestation",
    "arguments": {
      "document_hash": "sha256:abcdef1234567890abcdef1234567890abcdef1234567890abcdef1234567890",
      "presented_anchor": {
        "document_hash": "sha256:abcdef1234567890abcdef1234567890abcdef1234567890abcdef1234567890",
        "timestamp_claim": {
          "standard": "eIDAS Art.41 / RFC 3161-aligned",
          "timestamp": "2026-06-25T10:00:00Z",
          "algorithm": "sha256"
        }
      },
      "presented_timestamp": "2026-06-25T10:00:00Z",
      "expected_algorithm": "sha256"
    }
  },
  "id": 2
}
https://mcp.ainumbers.co/mcp
Export Artifacts
Download the §4 chain definition artifact or the §13.11 W3C VC view. Both art-121 and art-122 individually support W3C VC export.

Ask your agent

Copy this paragraph into Claude, OpenClaw, or any MCP-aware agent to run this whole workflow on the server and check one field that answers a real question.

Question: We notarise the executed agreement hash before filing. Is the document anchor in place, and what timestamp does the claim carry?
Run the AINumbers MCP tool `run_chain` with {"chain":"document-integrity-anchor"} and read `art-121-document-integrity-anchor.anchored`.
Verify: call `verify_execution_hash` (https://mcp.ainumbers.co/mcp) with `claimed_hash` set to `composite_execution_hash` and the full `composite_artifact`.
Ledger, for a human re-check: https://ledger.ainumbers.co/
PII rule: send synthetic or anonymised inputs only. The MCP server runs these kernels and logs no payloads.
Chain page: https://ainumbers.co/chaingraph/chains/document-integrity-anchor.html