{
  "schema": "varexis-public-evidence-record/0.3",
  "generated_at_utc": "2026-10-24T21:35:02.243Z",
  "record_id": "VXI-EXT-PROCUREMENT-X402-OFFER-INDEX-UNSIGNED-TERMS-BINDING-01-v1",
  "record_kind": "external_reference",
  "title": "x402 signed offers and unsigned selection indices",
  "system": "x402 Foundation",
  "evidence_family": "vendor_evidence_review",
  "index_status": "PUBLIC_SAFE_SOURCE_REVIEW",
  "evidence_state": "PRIMARY_DOCUMENTATION_REVIEW_ONLY",
  "canonical_question": "Can an x402 signed offer be bound to checkout terms using acceptIndex alone?",
  "near_questions": [
    "Is x402 acceptIndex protected by the offer signature?",
    "What binds an x402 offer to its selected requirements?",
    "Can an unsigned offer index substitute for amount and payee checks?",
    "How should an agent compare x402 signed terms?"
  ],
  "supported_claims": [
    {
      "claim": "The reviewed offer extension describes acceptIndex as an unsigned convenience field. Clients should check its range and compare the selected payment requirements with the signed fields. The signature-covered terms, including network, asset, payee and amount, are the binding evidence; the index itself is not authoritative.",
      "reliance": "DOCUMENTED_CAPABILITY_ONLY"
    }
  ],
  "not_demonstrated_claims": [
    "Independent verification of payment, delivery or deployed controls",
    "Actual server keys, offers and client matching behaviour have not been tested.",
    "Buyer deployment testing, live runtime enforcement, certification or permission to act",
    "Expanded capabilities or licences for existing INDEX executables"
  ],
  "public_summary": "The reviewed offer extension describes acceptIndex as an unsigned convenience field. Clients should check its range and compare the selected payment requirements with the signed fields. The signature-covered terms, including network, asset, payee and amount, are the binding evidence; the index itself is not authoritative.",
  "related_record_ids": [],
  "source_review": {
    "source_type": "official_external_documentation",
    "source_title": "Offer and Receipt Extension",
    "source_url": "https://raw.githubusercontent.com/x402-foundation/x402/4241d56cae2fb7ed06cd18e3a9ff2a3457b1ce54/specs/extensions/extension-offer-and-receipt.md",
    "checked_on": "2026-10-24",
    "candidate_record_id": "VXI-EXT-PROCUREMENT-X402-OFFER-INDEX-UNSIGNED-TERMS-BINDING-01-v1",
    "candidate_record_sha256": "cb8add96d539b37c1e8499201a7765fe846d76897599336dd7a9c2638b4927ea",
    "method": "Primary documentation reviewed for the published bounded statement.",
    "deployment_tested_by_varexis": false,
    "revalidation": "The delivered snapshot preserves the review date shown. Recheck current primary documentation and deployment context before relying on present applicability; payment does not trigger fresh research."
  },
  "answer_policy": {
    "classification": "DOCUMENTED_WITH_DEPLOYMENT_BOUNDARY",
    "bounded_answer": "The reviewed offer extension describes acceptIndex as an unsigned convenience field. Clients should check its range and compare the selected payment requirements with the signed fields. The signature-covered terms, including network, asset, payee and amount, are the binding evidence; the index itself is not authoritative.",
    "required_buyer_context": "Exact signed offer payload; Selected accepts entry and index; Field-by-field comparison and authorised signing key. Buyer deployment not inspected.",
    "missing_evidence": "A broader claim needs evidence matching the intended use. Payment does not upgrade the evidence state."
  },
  "private_boundary": "Raw logs, thresholds, private paths, source code, protected mechanisms and reconstruction-level details are excluded from public and paid delivery.",
  "decision_profile": {
    "schema": "varexis-vendor-evidence-review/1",
    "review_status": "documentation_review_only",
    "checked_on": "2026-10-24",
    "claim_to_check": "Can an x402 signed offer be bound to checkout terms using acceptIndex alone?",
    "documented_statement": {
      "status": "documented",
      "statement": "The reviewed offer extension describes acceptIndex as an unsigned convenience field. Clients should check its range and compare the selected payment requirements with the signed fields. The signature-covered terms, including network, asset, payee and amount, are the binding evidence; the index itself is not authoritative.",
      "source_ids": [
        "x402-offer-receipt"
      ]
    },
    "review_inference": {
      "status": "review_inference",
      "statement": "Detect changed offer selection without treating an unsigned pointer as approved terms. This is a review decision, not an observed buyer result.",
      "source_ids": [
        "x402-offer-receipt"
      ]
    },
    "buyer_evidence_required": [
      "Exact signed offer payload",
      "Selected accepts entry and index",
      "Field-by-field comparison and authorised signing key"
    ],
    "review_condition": {
      "status": "varexis_review_policy",
      "statement": "Do not rely on acceptIndex alone to bind the approved payment terms."
    },
    "unknowns": "Actual server keys, offers and client matching behaviour have not been tested.",
    "unknown_finding": {
      "status": "unknown",
      "statement": "Actual server keys, offers and client matching behaviour have not been tested."
    },
    "evidence_sources": [
      {
        "source_id": "x402-offer-receipt",
        "url": "https://raw.githubusercontent.com/x402-foundation/x402/4241d56cae2fb7ed06cd18e3a9ff2a3457b1ce54/specs/extensions/extension-offer-and-receipt.md",
        "final_url": "https://raw.githubusercontent.com/x402-foundation/x402/4241d56cae2fb7ed06cd18e3a9ff2a3457b1ce54/specs/extensions/extension-offer-and-receipt.md",
        "status": 200,
        "captured_at_utc": "2026-10-24T21:23:35.715Z",
        "sha256": "51151bd2b7dd174bc4a44b712234c074e45ca6c752c44ce077a94a4d97596ae9",
        "bytes": 41408,
        "title": "Offer and Receipt Extension",
        "hash_basis": "Decoded HTTP response body bytes",
        "rights_review": "Original factual paraphrase and source metadata only; Apache-2.0 repository captures retained privately and not redistributed.",
        "checked_on": "2026-10-24",
        "capture_status": 200,
        "claim_review_completed": true,
        "reviewed_sections": [
          "4.1.1 acceptIndex Handling",
          "4.5.1 Signer Authorization",
          "5.5 Receipt Verification",
          "5.2 Receipt Payload Fields",
          "11. Privacy Considerations"
        ],
        "version_context": "Pinned x402-foundation/x402 revision 4241d56cae2fb7ed06cd18e3a9ff2a3457b1ce54 captured 2026-10-24. Documentation revision, not evidence that any buyer deployment conforms."
      }
    ],
    "observed_deployment": false,
    "commercial_reliance_boundary": "Documentation review only; the buyer must establish applicability and actual outcomes. INDEX does not inspect or control the deployment.",
    "paid_value": {
      "decision_context": "Detect changed offer selection without treating an unsigned pointer as approved terms.",
      "free": "Complete review, sources, practical questions and limitations; may be saved locally.",
      "single_request": "Existing server-saved version-bound route snapshot for later authenticated retrieval.",
      "evidence_receipt": "The same snapshot plus the existing unsigned delivery receipt.",
      "excluded": [
        "Fresh vendor research",
        "Continuous monitoring or change alerts",
        "Testing the buyer configuration",
        "Private evidence or vendor certification"
      ],
      "integrity": "Hashes identify content versions; they do not prove truth or provide a signature."
    },
    "revalidation": {
      "trigger": "A saved purchase does not recheck the source or buyer configuration.",
      "specific_watch": "Recheck the pinned specification against the selected scheme, network, provider version and buyer evidence before relying on a current outcome."
    },
    "buyer_relevance": "Detect changed offer selection without treating an unsigned pointer as approved terms.",
    "refusal_conditions": [
      "Do not rely on acceptIndex alone to bind the approved payment terms."
    ]
  },
  "niche": {
    "niche_id": "agent-authority-action-evidence",
    "label": "Agent Authority & Action Evidence",
    "classification_id": "payments",
    "classification_label": "Agent Payments, Authority & Transaction Evidence",
    "topic_id": "payments",
    "buyer_intent": "Detect changed offer selection without treating an unsigned pointer as approved terms.",
    "comparison_role": "supplementary_discovery"
  },
  "paid_access_note": "The full published answer and boundaries are free. Paid access saves the selected route and source versions, with an unsigned receipt when purchased. Preview coverage before paying. Fresh research, bespoke assessment and protected evidence are excluded.",
  "service_route": {
    "request_guide": "/varexis-index/request.html",
    "request_workflow": "/varexis-index/request-workflow.json",
    "service_id": "single_request",
    "service_routes_url": "/varexis-index/service-routes.json",
    "payment_required": true,
    "availability_endpoint": "/api/index/capabilities",
    "operational_status": "AUTOMATIC_SERVICE_CAPABILITIES_GATED",
    "checkout_url": "/index-access"
  },
  "authority_boundary": "VAREXIS-INDEX informs evidence reliance. It does not provide advice, certification, deployment authority, security assurance, production approval, or guarantee.",
  "human_page": "/varexis-index/catalog.html#x402-offer-index-unsigned-terms-binding",
  "machine_readable_record": "/varexis-index/records/x402-offer-index-unsigned-terms-binding.json"
}