{"uid":"cap_G1CHYAtSK19VeLbcciwKJ","slug":"speraxos-erc-8004-agent-metadata-setter-3b6e34bd","name":"SperaxOS ERC-8004 Agent Metadata Setter","description":"AI-powered DeFi intelligence APIs payable via the x402 HTTP payment protocol. No API key required — pay per request with USDC on Base. Identity-only (SIWX) endpoints are free for wallets with an agentcash identity.","url":"https://chat.sperax.io/api/x402/tools/erc8004/setMetadata?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"key":{"type":"string","description":"Metadata key (e.g., \"version\", \"a2a.endpoint\", \"mcp.endpoint\", \"did\", \"ens\", \"x402.enabled\")"},"chain":{"type":"string","default":"bsc-testnet","description":"Blockchain where the agent is registered. Options: bsc-testnet, bsc-mainnet, ethereum, sepolia"},"value":{"type":"string","description":"Metadata value as a UTF-8 string"},"agentId":{"type":"number","description":"The token ID of the agent to update"}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_wnNbV0qFSaXSAAFig0rhD","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0xD74f5255D557944cf7Dd0E45FF521520002D5748","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Sets a metadata key-value pair on an ERC-8004 registered on-chain agent NFT across supported blockchains","exampleAgentPrompt":"Set the metadata key 'a2a.endpoint' to 'https://myagent.example.com/a2a' on my ERC-8004 agent with token ID 42 on BSC mainnet.","exampleUseCases":[{"title":"Register A2A endpoint for on-chain agent","prompt":"Update my on-chain agent with token ID 7 on BSC mainnet to set its 'a2a.endpoint' metadata to 'https://agents.myproject.io/agent7/a2a' so other agents can discover and communicate with it."},{"title":"Link DID identity to agent NFT","prompt":"Set the 'did' metadata key to 'did:ethr:0xabc123...' for my ERC-8004 agent token ID 15 deployed on Ethereum mainnet so it has a verifiable decentralized identity."},{"title":"Enable x402 payments on registered agent","prompt":"For my agent with token ID 99 on BSC testnet, set the metadata key 'x402.enabled' to 'true' so it can accept per-request USDC micropayments via the x402 protocol."}],"resultDescription":"A confirmation of the on-chain metadata update transaction, indicating that the specified key-value pair has been written to the ERC-8004 agent NFT record on the chosen blockchain.","failureModes":["Invalid or non-existent agent token ID returns an error indicating the agent cannot be found","Unsupported chain value causes a validation error listing accepted options","Empty or missing key/value fields result in a schema validation error","Caller wallet does not own or have permission to update the specified agent NFT","Blockchain network congestion or RPC failure causes a transaction timeout","Malformed metadata value (e.g. non-UTF-8 string) may be rejected"],"whenToPreferThis":"Use this endpoint when you need to write or update structured metadata fields on an ERC-8004 compliant agent NFT on a supported EVM chain. It is the right choice when configuring agent discovery properties (a2a.endpoint, mcp.endpoint, x402.enabled), linking identity documents (DID, ENS), or setting versioning metadata — especially within the SperaxOS / agentcash ecosystem where no traditional API key is required and payment is handled via x402 micropayments.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-20T18:54:29.897Z","isFirstParty":false,"canonicalSlug":"speraxos-erc-8004-agent-metadata-setter-3b6e34bd"}