{
      "tool_id": "art-124-content-credential-signature-verifier",
      "tool_version": "1.0.0",
      "display_name": "Content Credential Signature Verifier",
      "mcp_name": "verify_content_credential_signature",
      "mandate_type": "compliance_mandate",
      "wave": 23,
      "gpu": true,
      "url": "https://ainumbers.co/chaingraph/art-124-content-credential-signature-verifier.html",
      "description": "Verify-only node: callable in chains, carrying no compute-proof claim. Verify the COSE_Sign1 claim signature against a caller-supplied signer public key using crypto.subtle.verify (Ed25519/ES256/ES384/PS256). Trust-anchor membership, cert validity window, and revocation status are caller-supplied policy inputs: zero network, no OCSP. Emits ACCEPT or REFUSE verdict. PS256 (RSA-PSS) support means this kernel has no faithful sync in-guest verifier today, so its zkVM compute-integrity proof is out of the ocg-p18-deterministic profile's scope: not counted as proven.",
      "input_schema_ref": "chaingraph/art-124-content-credential-signature-verifier.html#manifest",
      "consumes": [
        "art-123-c2pa-manifest-validator"
      ],
      "feeds": [
        "art-125-provenance-ingredient-tree-resolver"
      ],
      "status": "live",
      "conformance_fixtures": true,
      "compute_capability": "server",
      "compute_images": [{"system":"sha256-source","image_id":"sha256:e9897ef4cb8f7cf9529ef898e949895809edb037f346eb0a0557216bb3875fd1","valid_from":"2026-07-10"}],
      "export_capability": [
        "xlsx",
        "csv",
        "pdf",
        "xbrl:ocg-ext"
      ]
    }