generated: '2026-09-19' method: probed source: https://api.liquidagent.ai/.well-known/agent-card.json card: file: a2a/liquidagent-ai-agent-card.json discovery: path: /.well-known/agent-card.json canonical: true host: api.liquidagent.ai also_served_at: /.well-known/agent.json note: >- The card is served from the API host at both the canonical A2A path and the pre-0.3 legacy path, byte-identical (3,429 bytes). The apex liquidagent.ai 307s both paths to www.liquidagent.ai, which returns a real 404 for each. Ownership is not in question: api.liquidagent.ai is the servers[] host of the provider's OpenAPI, the card's provider.organization is "Liquid Agent" with provider.url https://liquidagent.ai, the provider's own llms.txt, agents.txt, robots.txt, sitemap.xml and ERC-8004 registration all name this exact URL, and the open-source examples repo README lists it under "Discovery (machine-readable, self-hosted)". x-evidence: fetched: '2026-09-19' url: https://api.liquidagent.ai/.well-known/agent-card.json http_status: 200 content_type: application/json; charset=utf-8 body_bytes: 3429 body_parses_as: JSON object with AgentCard shape (name, description, url, provider, version, documentationUrl, capabilities, defaultInputModes, defaultOutputModes, skills) corroborating_probes: - url: https://api.liquidagent.ai/.well-known/agent.json http_status: 200 note: byte-identical legacy-path copy - url: https://liquidagent.ai/.well-known/agent-card.json http_status: 404 note: 307 to www.liquidagent.ai, which 404s - url: https://www.liquidagent.ai/.well-known/agent.json http_status: 404 - url: https://api.liquidagent.ai/a2a http_status: 404 note: No A2A JSON-RPC endpoint exists; the card's url is the REST API root. - url: https://api.liquidagent.ai/.well-known/erc8004.json http_status: 200 note: The ERC-8004 registration independently lists the card as service "A2A" with version "0.3.0". agent_card: name: Liquid Agent — Tokenized Stock Index description: Agent-native tokenized-stock index on Base. Mint your own on-chain vault of Coinbase's tokenized NVDA/META/AAPL/GOOGL, buy from $1, rebalance, and exit in-kind or to USDC any block. No oracle, no token, fully self-custodial. Reads free; transactions return unsigned calldata the agent signs. url: https://api.liquidagent.ai version: 1.0.0 documentation_url: https://api.liquidagent.ai/v1/guide provider: organization: Liquid Agent url: https://liquidagent.ai capabilities: streaming: false push_notifications: false state_transition_history: false default_input_modes: [application/json] default_output_modes: [application/json] security_schemes: null skill_count: 7 skills: - {id: discover-index, name: Discover the stock index, tags: [stocks, index, prices, invest], rest: get_v1_basket} - {id: create-vault, name: Create your own vault, tags: [vault, create, self-custody], rest: post_v1_create-vault} - {id: buy-stocks, name: Buy the tokenized-stock basket, tags: [buy, invest, stocks, deposit], rest: post_v1_buy} - {id: rebalance, name: Rebalance to target weights, tags: [rebalance, portfolio], rest: post_v1_rebalance} - {id: redeem, name: Exit any block, tags: [redeem, exit, withdraw], rest: post_v1_redeem} - {id: basket-signals, name: Get basket rebalancing signals (paid), tags: [signals, analytics, rebalance, stocks, x402, paid], rest: getV1Signals, paid: 0.04 USDC via x402} - {id: gas-sponsor, name: Sponsor gas for a smart-wallet transaction (paid, x402), tags: [gas, paymaster, erc-4337, erc-7677, eip-7702, x402, paid, base], rest: [postV1Gas, postV1GasSolana], paid: from 0.03 USDC via x402} conformance: spec: A2A 1.0.0 grade: flavored protocol_version: null preferred_transport: null transport: null hard_checks: capabilities_is_object: true protocol_version_present: false skills_is_array: true optional_fields: default_input_modes: true default_output_modes: true preferred_transport: false grade_basis: >- Graded against the A2A 1.0.0 hard checks. capabilities is an OBJECT (pass: streaming, pushNotifications, stateTransitionHistory declared as fields). skills is an ARRAY (pass: seven skills, each with id, name, description, tags and examples). protocolVersion is ABSENT (fail) - neither a top-level protocolVersion (0.3 shape) nor a supportedInterfaces[].protocolVersion (1.0 shape) is declared anywhere in the card, so a reader cannot tell which A2A revision it targets. The provider's ERC-8004 registration says "0.3.0" for the A2A service, but that statement lives in a different document. One hard failure makes the grade flavored regardless of the optional fields, both of which (defaultInputModes, defaultOutputModes) are present. deviations: - field: protocolVersion observed: absent note: No protocolVersion at the top level and no supportedInterfaces[] block. Hard failure. - field: url observed: https://api.liquidagent.ai (the REST API root) note: >- A2A expects url to be the agent's JSON-RPC (or declared transport) endpoint. This card points at the REST base URL; https://api.liquidagent.ai/a2a returns 404 and a JSON-RPC message/send has no documented endpoint. The card is a discovery and capability description, not a callable A2A surface - an A2A client that follows url will reach the REST index document, not a task endpoint. - field: preferredTransport / supportedInterfaces observed: absent note: No transport is declared in either the 0.3 (preferredTransport) or 1.0 (supportedInterfaces) form. - field: securitySchemes / security observed: absent note: >- Two of the seven skills are paid over x402 and the free ones accept optional SIWX identity, but the card declares no security scheme; the payment requirement is stated only in prose ("PAID $0.04 USDC via x402") inside skill descriptions and is not machine-readable from the card. The a2a-x402 payment extension is not declared under capabilities.extensions. - field: skills[].inputModes / outputModes observed: absent per skill note: Only the card-level defaults (application/json) are declared; harmless. - field: skills observed: seven skills, two of them paid note: >- The card omits set-weights, send and publish, which the REST contract and the ERC-8004 services list do expose; the ERC-8004 "web" service lists set-weights as a skill that this card does not carry. Not a spec violation - recorded because the two provider-published skill lists disagree. surface_relationship: note: >- Liquid Agent publishes one callable machine surface - the 17-operation REST API - and describes it through several discovery documents (this card, the OpenAPI/x402 manifest, the x402 resource catalog, llms.txt, agents.txt, ERC-8004). The card is a projection of the REST API (every skill maps to a REST operation; see agent_card.skills[].rest) rather than a separate A2A task surface. There is no MCP server.