{ "builder_version": "nomos-compatibility-map-builder/1.0.0", "canonical_url": "https://agentnomos.com/.well-known/nomos-compatibility.json", "claim_basis_vocabulary": { "CONCEPTUAL_MAPPING": "an argued correspondence between concepts. No artefact and no measurement backs it.", "LIVE_RUNTIME": "measured against a running system at build time.", "OFFICIAL_SPECIFICATION": "read from the technology's own official specification at checked_at.", "PUBLIC_CONTRACT": "read from a document NOMOS itself publishes." }, "compatibility_digest": "sha256:cbc4a6b2ede486a4de7db8fd84facbdd65c9080bfe90f20845f287bedb1b582a", "content_digest": "sha256:6ca0035cb68d55479e6a94af6fd848ec89ab3e995063b554bf8fdb6d7b7f1704", "description": "How the NOMOS S0-S10 trust chain relates to external agent, commerce and ledger technologies. Each entry separates what the external specification says from what NOMOS actually implements. A relationship is not compatibility, and no entry states that either side implements the other.", "digest_rule": { "canonical_json": "json.dumps(obj, sort_keys=True, separators=(\",\",\":\"), ensure_ascii=False).encode(\"utf-8\")", "compatibility_digest": "sha256 of canonical JSON of this document with the member compatibility_digest removed", "content_digest": "sha256 of canonical JSON of this document with the members generated_at, content_digest and compatibility_digest removed" }, "generated_at": "2026-08-08T06:22:50Z", "human_readable": { "note": "A static rendering of this document and nothing else. It is generated from the canonical JSON and adds no statement that is not already here. This document is authoritative.", "url": "https://agentnomos.com/compatibility/" }, "implementation_status_vocabulary": { "DISCOVERY_BRIDGE": "a NOMOS document points at, or is pointed at from, this technology's discovery surface, and nothing more.", "IMPLEMENTED_WITH": "measured running in a NOMOS surface at build time.", "INTEROPERABLE": "a recorded interoperation exists.", "NOT_IMPLEMENTED": "NOMOS does not implement or use this technology. Stated so that a mapping is never mistaken for an integration." }, "map_version": "1.0.0", "name": "NOMOS Machine Economy Trust Chain Compatibility Map", "nomos_model": { "capability_manifest": "https://agentnomos.com/.well-known/nomos-capabilities.json", "capability_manifest_digest": "sha256:780fcd76d643f37ee556258ced72d3c34704b7887ca7893b2c387cb8c89ea4de", "model": "S0-S10", "stage_count": 11, "stages": [ { "id": "S0", "name": "Frequency / Freshness" }, { "id": "S1", "name": "Presence" }, { "id": "S2", "name": "Identity" }, { "id": "S3", "name": "Capability" }, { "id": "S4", "name": "Intent / Task Fit" }, { "id": "S5", "name": "Offer" }, { "id": "S6", "name": "Deal / Authorization" }, { "id": "S7", "name": "Execution / Delivery" }, { "id": "S8", "name": "Proof / Verifiability" }, { "id": "S9", "name": "Reliability / Outcomes" }, { "id": "S10", "name": "Governance / Immune Control" } ] }, "nomos_stages_not_attributed": [ { "reason": "No specification examined here defines an admission decision that a separate process signs and that can refuse a live request on the resource owner's behalf. Attributing S6 to any of them would be the error this document exists to avoid.", "stage": "S6", "stage_name": "Deal / Authorization" }, { "reason": "No specification examined here defines a policy lifecycle with governed status transitions. NOMOS S10 is also observational: it changes no production request.", "stage": "S10", "stage_name": "Governance / Immune Control" }, { "reason": "None of the technologies examined here defines a freshness measure that is recomputed against the clock at decision time, so no mapping is offered.", "stage": "S0", "stage_name": "Frequency / Freshness" } ], "not_claimed": [ "NOMOS is not an industry standard and this map does not present it as one.", "No technology listed here implements NOMOS, and NOMOS does not implement any of their trust models on their behalf.", "No organisation named here has reviewed, approved or endorsed NOMOS, and no relationship recorded here is a partnership.", "This map is not a compatibility certification. It is a statement of which relationships were measured, which were read from a specification, and which are argued.", "A technology appearing here does not mean a NOMOS product supports it. Read nomos_implementation.status for that, and NOT_IMPLEMENTED means exactly what it says.", "Version and status values are point-in-time observations. Follow official_sources for the current text.", "Nothing here activates, enables or performs a payment or a ledger transaction." ], "publisher": { "name": "NOMOS", "operator": "FeedOracle Technologies", "url": "https://agentnomos.com" }, "reading_rules": [ "A relationship is not compatibility. Only IMPLEMENTED_WITH and INTEROPERABLE say that something runs or was carried out; everything else describes a correspondence between ideas.", "spec_relationship describes the external specification. nomos_implementation describes what NOMOS does. Read them separately: a mapping under spec_relationship is not evidence of an integration.", "external_concept values are terms that occur verbatim in the official source document cited beside them. That the term exists is checked; what it means in that specification is for the specification to say.", "observed_version and spec_status are observations made at checked_at from the sources named. They are not a restatement of those specifications and may be out of date.", "Each mapping carries a distinction: the sentence saying how the two concepts differ. A mapping without one would read as an equivalence." ], "relationship_vocabulary": { "COMPLEMENTARY": "the technology solves an adjacent part of the same chain. Adjacent is not overlapping and not interchangeable.", "DISCOVERY_BRIDGE": "an existing discovery surface carries a pointer to NOMOS metadata. A pointer is not an integration.", "IMPLEMENTED_WITH": "NOMOS actually uses this technology in a runtime that was measured, not described.", "INTEROPERABLE": "a real technical interoperation between NOMOS and this technology was carried out and recorded. Not used unless such a record exists.", "RELATED": "the subject areas overlap. No technical interoperation has been attempted or proven." }, "schema": "nomos.machine-economy.compatibility.v1", "technologies": [ { "category": "agent interoperability protocol", "full_name": "Agent2Agent Protocol", "name": "A2A", "nomos_implementation": { "basis": "PUBLIC_CONTRACT", "evidence": [ { "expect_status": 200, "measured_at": "2026-08-07T14:05:00Z", "measured_status": 200, "role": "publisher document at the A2A agent card path, carrying the NOMOS trust chain pointer", "url": "https://agentnomos.com/.well-known/agent-card.json" } ], "limitations": [ "Measured against the official A2A JSON Schema for the protocol version each document itself declares, the published documents validate. That is a statement about the document, not about the agent behind it.", "The extension is declared with required false. A client that does not understand it is expected to ignore it, and nothing in NOMOS depends on a client reading it.", "No A2A interoperation has been carried out: no client has been driven through a task against these agents as part of this statement. A card that validates is not a handshake, which is why this stays a bridge and not an interoperation.", "Serving a valid document at a standard path is not conformance of the SERVICE to the standard, and this map does not claim conformance." ], "scope": "NOMOS publishes documents at the A2A agent card well-known path. Each one declares the NOMOS trust chain as an optional AgentExtension under capabilities.extensions, carrying the capability manifest and this map in the extension's params. That declaration is the bridge; nothing else about A2A is implemented by the NOMOS trust chain.", "status": "DISCOVERY_BRIDGE" }, "spec_relationship": { "basis": "OFFICIAL_SPECIFICATION", "mappings": [ { "basis": "OFFICIAL_SPECIFICATION", "distinction": "A2A discovery answers which agent exists and how to reach it. NOMOS S1 resolves a subject identifier through a resolver to a signed scan receipt, and an unsigned or missing scan is a refusal. Same word, different question.", "external_concept": "Agent Card", "external_concept_source": "https://a2a-protocol.org/v1.0.1/topics/agent-discovery/", "nomos_stage": "S1", "nomos_stage_name": "Presence", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "An A2A card signature authenticates the CARD. NOMOS S2 authenticates the CALLER of a request, and does so with a shared secret over TLS, which is not proof of key possession. Neither is a substitute for the other.", "external_concept": "Agent Card Signature", "external_concept_source": "https://a2a-protocol.org/v1.0.1/spec/a2a.json", "nomos_stage": "S2", "nomos_stage_name": "Identity", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "A2A skills are declared by the agent in its own card. NOMOS S3 derives capability from the installed handler by static analysis. A declaration and a derivation are not the same evidence.", "external_concept": "AgentSkill", "external_concept_source": "https://a2a-protocol.org/v1.0.1/specification/", "nomos_stage": "S3", "nomos_stage_name": "Capability", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "A2A models the lifecycle of a task between two agents. NOMOS S4 compares a typed, digest-sealed intent document against the offer in force under a deterministic evaluator. Related subject area, no shared document.", "external_concept": "Task", "external_concept_source": "https://a2a-protocol.org/v1.0.1/specification/", "nomos_stage": "S4", "nomos_stage_name": "Intent / Task Fit", "relation": "RELATED" } ], "reason": "A2A standardises how agents find each other, describe themselves and run a task between them. NOMOS states what happened to a single request and how strong that statement is. Adjacent parts of the same chain; no shared document, no shared verdict.", "relationship": "COMPLEMENTARY", "stages_deliberately_not_mapped": [ { "nomos_stage": "S6", "reason": "A2A defines no admission decision that can refuse a request on behalf of a resource owner." } ] }, "standard_source": { "checked_at": "2026-08-07T14:05:00Z", "observed_version": "1.0.1", "official_sources": [ "https://a2a-protocol.org/v1.0.1/specification/", "https://a2a-protocol.org/v1.0.1/topics/agent-discovery/", "https://a2a-protocol.org/v1.0.1/spec/a2a.json", "https://github.com/a2aproject/A2A/releases/tag/v1.0.1" ], "source_documents": [ { "bytes": 61591, "role": "A2A agent discovery topic, naming the well-known agent card path", "sha256": "sha256:6aff811ebda7f9e11c94c2a45f35bf61139b103c9358ce35208b29b1608dbdf9", "url": "https://a2a-protocol.org/v1.0.1/topics/agent-discovery/" }, { "bytes": 75186, "role": "A2A JSON Schema artefact published alongside v1.0.1", "sha256": "sha256:ba4b702b5edbdcbfe972c272484eb38e1fcd72af3c0b7eaa114b50e97455d8dd", "url": "https://a2a-protocol.org/v1.0.1/spec/a2a.json" }, { "bytes": 603887, "role": "A2A protocol specification, published version v1.0.1", "sha256": "sha256:033b13b5ef1ee001ad207a54e48863beb5956e632c5f407f67dd596dca3cb4db", "url": "https://a2a-protocol.org/v1.0.1/specification/" } ], "spec_status": "RELEASED", "version_note": "Two official surfaces of the same publisher disagree in wording: the release list and the published documentation versions both include v1.0.1 (released 2026-05-28), while the body text of the specification page states 'Latest Released Version 1.0.0'. The highest published release is recorded here." } }, { "category": "on-chain agent identity, reputation and validation registries", "full_name": "ERC-8004 Trustless Agents", "name": "ERC-8004", "nomos_implementation": { "basis": "CONCEPTUAL_MAPPING", "evidence": [], "limitations": [ "The proposal is in Draft status. Its content may change, and this map records what it said at checked_at.", "The proposal states of itself that it 'cannot cryptographically guarantee that advertised capabilities are functional and non-malicious'. An entry in such a registry is therefore not evidence that a capability works, and this map does not treat it as such." ], "scope": "Nothing in NOMOS reads from or writes to an ERC-8004 registry. There is no agent identifier, no registration file and no on-chain entry for NOMOS under this proposal.", "status": "NOT_IMPLEMENTED" }, "spec_relationship": { "basis": "OFFICIAL_SPECIFICATION", "mappings": [ { "basis": "OFFICIAL_SPECIFICATION", "distinction": "An on-chain, portable agent handle resolving to a registration file. NOMOS S2 authenticates a caller against an operator-held credential register. Different trust roots; nothing is shared.", "external_concept": "Identity Registry", "external_concept_source": "https://eips.ethereum.org/EIPS/eip-8004", "nomos_stage": "S2", "nomos_stage_name": "Identity", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "Both concern independent checkability of a claim. ERC-8004 records validator responses on chain; NOMOS S8 verifies Merkle membership against a ledger transaction. Related purpose, unrelated mechanism.", "external_concept": "Validation Registry", "external_concept_source": "https://eips.ethereum.org/EIPS/eip-8004", "nomos_stage": "S8", "nomos_stage_name": "Proof / Verifiability", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "ERC-8004 records signed client feedback values on chain. NOMOS S9 counts outcomes into immutable snapshots and derives NO score, no ranking and no cross-party comparison. The relation is to the subject area, and specifically not to a shared output.", "external_concept": "Reputation Registry", "external_concept_source": "https://eips.ethereum.org/EIPS/eip-8004", "nomos_stage": "S9", "nomos_stage_name": "Reliability / Outcomes", "relation": "RELATED" } ], "reason": "The subject areas overlap in three places. No technical interoperation between NOMOS and any ERC-8004 registry has been attempted or proven, so the relationship stops at RELATED.", "relationship": "RELATED", "stages_deliberately_not_mapped": [ { "nomos_stage": "S6", "reason": "The registries record identity, feedback and validation. They issue no authorization decision for a specific request." }, { "nomos_stage": "S10", "reason": "The proposal defines no policy lifecycle with a governed status transition." } ] }, "standard_source": { "checked_at": "2026-08-07T14:05:00Z", "observed_version": null, "official_sources": [ "https://eips.ethereum.org/EIPS/eip-8004", "https://github.com/ethereum/ERCs/blob/master/ERCS/erc-8004.md" ], "source_documents": [ { "bytes": 24470, "role": "ERC-8004 Trustless Agents, source markdown from the ethereum/ERCs repository", "sha256": "sha256:249dc3d96ad7bbe4afd25cacd14be942eb87751abcf1608bab19a610f3c3f8a9", "url": "https://eips.ethereum.org/EIPS/eip-8004" } ], "spec_status": "Draft", "version_note": "An ERC carries a status, not a version. The source markdown declared status Draft, type Standards Track, category ERC, created 2025-08-13." } }, { "category": "model-to-tool integration protocol", "full_name": "Model Context Protocol", "name": "MCP", "nomos_implementation": { "basis": "LIVE_RUNTIME", "evidence": [ { "expect_status": 200, "measured_at": "2026-08-07T14:05:00Z", "measured_status": 200, "role": "Official MCP Registry entry io.github.AgentNOMOS/nomos-crossborder-broker, status active", "url": "https://registry.modelcontextprotocol.io/v0/servers?search=nomos" } ], "limitations": [ "The server negotiated MCP protocol revision 2024-11-05 when measured, which is older than the specification revision recorded above. This states what runs; it is not a conformance claim about the current revision.", "The MCP surface is NOT the governed route cohort of the capability manifest. No stage of the NOMOS trust chain is proven for MCP tool calls.", "Being listed in the registry is a publication, not a review, an approval or an endorsement by the registry operator." ], "scope": "An MCP server operated by the publisher answers the MCP initialize handshake and advertises the tools capability. It is listed in the Official MCP Registry.", "status": "IMPLEMENTED_WITH" }, "spec_relationship": { "basis": "OFFICIAL_SPECIFICATION", "mappings": [ { "basis": "OFFICIAL_SPECIFICATION", "distinction": "The registry answers which servers exist and where they are. NOMOS S1 resolves a subject identifier to a signed scan receipt at decision time. Being listed is not being resolved.", "external_concept": "MCP Registry", "external_concept_source": "https://modelcontextprotocol.io/registry", "nomos_stage": "S1", "nomos_stage_name": "Presence", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "MCP tools, resources and prompts are what a server offers, as the server describes them. NOMOS S3 reads capability out of the installed handler by static analysis and refuses to guess from a name.", "external_concept": "Tools", "external_concept_source": "https://modelcontextprotocol.io/specification/2026-07-28", "nomos_stage": "S3", "nomos_stage_name": "Capability", "relation": "RELATED" } ], "reason": "MCP standardises how a model reaches tools and data. NOMOS governs and records what happened when a request was served. Adjacent parts of the same chain.", "relationship": "COMPLEMENTARY", "stages_deliberately_not_mapped": [ { "nomos_stage": "S6", "reason": "MCP negotiates capabilities between a client and a server; it defines no signed authorization decision issued by a third process." } ] }, "standard_source": { "checked_at": "2026-08-07T14:05:00Z", "observed_version": "2026-07-28", "official_sources": [ "https://modelcontextprotocol.io/specification/2026-07-28", "https://modelcontextprotocol.io/registry", "https://registry.modelcontextprotocol.io/openapi.yaml" ], "source_documents": [ { "bytes": 274889, "role": "MCP Registry documentation", "sha256": "sha256:a6bf1b8739d779deb043a7fda6f54a3628887db16c60ee816cf66cd6d4f9574c", "url": "https://modelcontextprotocol.io/registry" }, { "bytes": 287426, "role": "MCP specification, revision 2026-07-28", "sha256": "sha256:4fe6831eab017a3d1e8632dd48dc3b9407efe333a58b91f3c565789696402b1e", "url": "https://modelcontextprotocol.io/specification/2026-07-28" } ], "spec_status": "RELEASED", "version_note": "The specification is versioned by revision date. The Official MCP Registry service reported version 1.8.1 at checked_at; its OpenAPI document declares title 'Official MCP Registry'." } }, { "category": "merchant-side agent recognition protocol", "full_name": "Trusted Agent Protocol", "name": "Visa Trusted Agent Protocol", "nomos_implementation": { "basis": "CONCEPTUAL_MAPPING", "evidence": [], "limitations": [ "The specification names no version and no date, so no statement here can be pinned to a specification version.", "Participation in the protocol is described as requiring agents to be onboarded to payment schemes. Nothing in this map states or implies that NOMOS is such an agent." ], "scope": "NOMOS neither produces nor verifies Trusted Agent Protocol signatures, and is not onboarded to any payment scheme as an agent under it.", "status": "NOT_IMPLEMENTED" }, "spec_relationship": { "basis": "OFFICIAL_SPECIFICATION", "mappings": [ { "basis": "OFFICIAL_SPECIFICATION", "distinction": "The protocol authenticates the calling agent with an HTTP Message Signature verified against keys of agents onboarded to payment schemes. NOMOS S2 authenticates with a shared secret over TLS and the caller holds no signing key. The trust roots differ and so does the strength; this is expressly not an equivalence.", "external_concept": "Agent Recognition Signature", "external_concept_source": "https://developer.visa.com/capabilities/trusted-agent-protocol/trusted-agent-protocol-specifications", "nomos_stage": "S2", "nomos_stage_name": "Identity", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "The protocol conveys that an agent acts with commerce intent for a specific merchant interaction. NOMOS S4 compares a typed intent document against the offer in force under a deterministic evaluator. Related subject, different artefact.", "external_concept": "commerce intent", "external_concept_source": "https://developer.visa.com/capabilities/trusted-agent-protocol/trusted-agent-protocol-specifications", "nomos_stage": "S4", "nomos_stage_name": "Intent / Task Fit", "relation": "RELATED" } ], "reason": "Both describe how a party receiving a request decides what it knows about the caller. No technical interoperation has been attempted or proven, so the relationship stops at RELATED.", "relationship": "RELATED", "stages_deliberately_not_mapped": [ { "nomos_stage": "S6", "reason": "The protocol lets a merchant recognise an agent and its declared intent. The merchant's own decision is left to the merchant, so this is not the NOMOS S6 authorization decision and must not be equated with it." }, { "nomos_stage": "S10", "reason": "The specification defines no governance or policy lifecycle." } ] }, "standard_source": { "checked_at": "2026-08-07T14:05:00Z", "observed_version": null, "official_sources": [ "https://developer.visa.com/capabilities/trusted-agent-protocol/trusted-agent-protocol-specifications", "https://developer.visa.com/capabilities/trusted-agent-protocol/docs-getting-started" ], "source_documents": [ { "bytes": 57571, "role": "Trusted Agent Protocol specification, Visa Developer Center", "sha256": "sha256:8049fc111940c3ef49d08f3c799c3243c106c2d27412585b6ead837a25bba852", "url": "https://developer.visa.com/capabilities/trusted-agent-protocol/trusted-agent-protocol-specifications" } ], "spec_status": "PUBLISHED_WITHOUT_VERSION_IDENTIFIER", "version_note": "No version identifier and no date appear anywhere in the published specification text. This is a measured absence: the specification page was retrieved and searched, and it contains no occurrence of a version string." } }, { "category": "public settlement ledger", "full_name": "XRP Ledger", "name": "XRPL", "nomos_implementation": { "basis": "LIVE_RUNTIME", "evidence": [ { "expect_status": 200, "measured_at": "2026-08-07T14:05:00Z", "measured_status": 200, "role": "the capability manifest states the S8 assurance, its scope and its stated limits", "url": "https://agentnomos.com/.well-known/nomos-capabilities.json" }, { "expect_status": 200, "measured_at": "2026-08-07T14:05:00Z", "measured_status": 200, "role": "public XRPL agentic payments surface", "url": "https://agentnomos.com/xrpl-agentic-payments/" } ], "limitations": [ "XRPL is settlement and ledger infrastructure. The official introduction to the XRP Ledger contains no occurrence of the terms 'agent identity' or 'agent trust'; this was measured, not assumed.", "Membership proofs are not published, so a ledger transaction alone does not let an outside party bind it to a specific execution.", "No XRPL transaction is performed by this map, and no payment is activated by it." ], "scope": "Two distinct and separately scoped uses. First, S8 anchor proofs: Merkle roots for the subject are committed in XRP Ledger transactions, and membership plus coverage are re-verified before an admission decision. Second, a public preflight route quotes payment on the XRPL mainnet network identifier. The two do not depend on each other.", "status": "IMPLEMENTED_WITH" }, "spec_relationship": { "basis": "LIVE_RUNTIME", "mappings": [ { "basis": "LIVE_RUNTIME", "distinction": "Anchor proofs for the subject are bound to XRP Ledger transactions, and incomplete coverage refuses the request at admission. This is the one place where the ledger is load-bearing for the trust chain.", "external_concept": "XRP Ledger", "external_concept_source": "https://xrpl.org/docs/introduction/what-is-the-xrp-ledger", "nomos_stage": "S8", "nomos_stage_name": "Proof / Verifiability", "relation": "IMPLEMENTED_WITH" } ], "reason": "NOMOS S8 verifies Merkle membership against real XRP Ledger transactions before an admission decision is issued. The ledger supplies evidence; it supplies no trust semantics.", "relationship": "IMPLEMENTED_WITH", "stages_deliberately_not_mapped": [ { "nomos_stage": "S7", "reason": "NOMOS S7 is execution and delivery of an API response, not settlement. The governed route cohort is free and settles nothing, so mapping a settlement ledger onto S7 would misdescribe both." }, { "nomos_stage": "S10", "reason": "A ledger records transactions. It defines no policy lifecycle and no governance semantics." } ] }, "standard_source": { "checked_at": "2026-08-07T14:05:00Z", "observed_version": "rippled 3.3.0", "official_sources": [ "https://xrpl.org/docs/introduction/what-is-the-xrp-ledger", "https://github.com/XRPLF/rippled/releases/tag/3.3.0" ], "source_documents": [ { "bytes": 383758, "role": "official introduction to the XRP Ledger", "sha256": "sha256:869f26c4e2d877007e69f3068da6fd7bc4413efc70fa605593910b15cbb664b1", "url": "https://xrpl.org/docs/introduction/what-is-the-xrp-ledger" } ], "spec_status": "PUBLIC_PRODUCTION_LEDGER_NOT_AN_AGENT_TRUST_STANDARD", "version_note": "The XRP Ledger is not a specification with a version that applies here; the value records the latest published release of the reference server at checked_at. The ledger evolves by amendments, not by a document version." } }, { "category": "agentic payment protocol", "extension_candidate": { "architecture_fit": "The x402 version 2 extensions member is a map from an extension identifier to an object carrying info and schema. A NOMOS entry would be one such key. This is a statement about where such an entry would fit, not that one exists.", "candidate": "nomos-trust-chain", "not_registered_note": "This candidate has not been submitted to, and is not listed in, the x402 extensions directory of the canonical repository.", "purpose": "bind trust metadata to agentic payment workflows", "status": "NOT_IMPLEMENTED", "technology": "x402" }, "full_name": "x402 payment protocol", "name": "x402", "nomos_implementation": { "basis": "LIVE_RUNTIME", "evidence": [ { "expect_status": 402, "measured_at": "2026-08-07T14:05:00Z", "measured_status": 402, "role": "live x402 version 2 payment-required challenge, returned to an unpaid request", "url": "https://agentnomos.com/xrpl-agentic-payments/api/x402/preflight" }, { "expect_status": 200, "measured_at": "2026-08-07T14:05:00Z", "measured_status": 200, "role": "public x402 resource discovery document for the publisher", "url": "https://agentnomos.com/.well-known/x402" } ], "limitations": [ "The governed route cohort of the capability manifest is free: amount 0, currency NONE, settlement_required false. x402 is NOT part of the proven S0-S10 chain, and no stage of that chain is claimed for the x402 routes.", "No x402 extension is implemented. The measured challenge carries no extensions member; bazaar, offer-receipt and payment-identifier are not in use.", "This map neither performs nor enables a payment." ], "scope": "Public NOMOS preflight routes answer an unpaid request with HTTP 402 and an x402 version 2 PaymentRequired object. A public x402 discovery document lists those routes.", "status": "IMPLEMENTED_WITH" }, "spec_relationship": { "basis": "LIVE_RUNTIME", "mappings": [ { "basis": "OFFICIAL_SPECIFICATION", "distinction": "The bazaar extension lets a resource server declare its endpoint specification so facilitators can catalog it. NOMOS S3 derives capability from installed code rather than from a declaration. NOMOS does not implement the bazaar extension.", "external_concept": "resource discovery and cataloging", "external_concept_source": "https://github.com/x402-foundation/x402/blob/main/specs/extensions/bazaar.md", "nomos_stage": "S3", "nomos_stage_name": "Capability", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "An x402 accepts entry states the payment terms for one response. A NOMOS offer is an immutable, content-addressed artefact whose lifecycle status is the fold of an append-only event chain. Terms in a response are not an artefact with a history.", "external_concept": "PaymentRequirements", "external_concept_source": "https://github.com/x402-foundation/x402/blob/main/specs/x402-specification-v2.md", "nomos_stage": "S5", "nomos_stage_name": "Offer", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "x402 settlement confirms that a payment was made. NOMOS S7 records that the backend response was delivered and hashes its exact bytes. The governed route cohort carries no settlement at all.", "external_concept": "SettlementResponse", "external_concept_source": "https://github.com/x402-foundation/x402/blob/main/specs/x402-specification-v2.md", "nomos_stage": "S7", "nomos_stage_name": "Execution / Delivery", "relation": "RELATED" }, { "basis": "OFFICIAL_SPECIFICATION", "distinction": "The offer and receipt extension adds server-side signatures over payment terms and outcomes. NOMOS signs execution receipts today, but not in that extension's format and not under that extension. The relation is to the idea, not to an implementation.", "external_concept": "Signed receipts", "external_concept_source": "https://github.com/x402-foundation/x402/blob/main/specs/extensions/extension-offer-and-receipt.md", "nomos_stage": "S8", "nomos_stage_name": "Proof / Verifiability", "relation": "RELATED" } ], "reason": "Public NOMOS preflight routes return x402 version 2 payment-required challenges. This was measured over HTTPS, not read off a document.", "relationship": "IMPLEMENTED_WITH", "stages_deliberately_not_mapped": [ { "nomos_stage": "S6", "reason": "x402 states what a payment must satisfy. It defines no admission decision about whether the caller may act at all, independently of payment." } ] }, "standard_source": { "checked_at": "2026-08-07T14:05:00Z", "observed_version": "2", "official_sources": [ "https://x402.org", "https://github.com/x402-foundation/x402/blob/main/specs/x402-specification-v2.md", "https://github.com/x402-foundation/x402/blob/main/specs/extensions/bazaar.md", "https://github.com/x402-foundation/x402/blob/main/specs/extensions/extension-offer-and-receipt.md", "https://github.com/x402-foundation/x402/blob/main/specs/extensions/payment_identifier.md" ], "source_documents": [ { "bytes": 24925, "role": "x402 bazaar discovery extension", "sha256": "sha256:e7cefd70e4e388333a2a5fdd20056e3341a781e475cc19e028e58a5c7ea44822", "url": "https://github.com/x402-foundation/x402/blob/main/specs/extensions/bazaar.md" }, { "bytes": 41408, "role": "x402 offer and receipt extension", "sha256": "sha256:51151bd2b7dd174bc4a44b712234c074e45ca6c752c44ce077a94a4d97596ae9", "url": "https://github.com/x402-foundation/x402/blob/main/specs/extensions/extension-offer-and-receipt.md" }, { "bytes": 33815, "role": "x402 protocol specification version 2, canonical upstream repository", "sha256": "sha256:278bf9b10644bcf9dfc1bb3a865d5481bbd4045cdb8fdc56f98b2dbdcdfec364", "url": "https://github.com/x402-foundation/x402/blob/main/specs/x402-specification-v2.md" } ], "spec_status": "PUBLISHED_AND_ACTIVELY_REVISED", "version_note": "The specification document states 'Protocol Version: 2' and its version history records v2.0 dated 2025-12-9. The canonical repository is x402-foundation/x402; the widely cited coinbase/x402 repository is a fork of it and its copy of the v2 specification differed from the canonical one at checked_at." } } ] }