{"uid":"cap_nKqt6W19klyTLKmqbOttU","slug":"discovery-hugen-tokyo-58f89c2a","name":"MCP Gateway API Key Top-Up","description":"Top up MCP Gateway API key balance — $1.00 USDC credited per call. API keys let agents use 58 MCP Gateway tools (DeFi, Weather, Security, Domain, Intel, etc.) without wallet setup. Create a free key at POST /keys/create, then top up here.","url":"https://discovery.hugen.tokyo/keys/topup","method":"POST","headers":{},"bodySchema":{"type":"object","required":["key"],"properties":{"key":{"type":"string","title":"Key","description":"API key to top up"}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"1","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"unknown","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":"$1/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"1","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"1","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_oTHouN2YRtdly8mlRGsUH","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"1","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Credits $1.00 USD to an MCP Gateway API key balance via a $1.00 USDC payment, enabling the key to call 58 MCP Gateway tools without per-call wallet setup.","exampleAgentPrompt":"Add $1 of credit to my MCP Gateway API key mgk_test_12345 so I can start using the DeFi and weather tools without setting up a wallet.","exampleUseCases":null,"resultDescription":"Returns a confirmation that $1.00 USD was credited to the specified API key, the new running balance (e.g. $1.05), a notice about the x402 payment on Base, and alternative access options including MCP server and broker endpoints.","failureModes":["Invalid or missing API key — key not recognized, no credit applied","Payment failure — USDC transaction on Base not confirmed, balance unchanged","Malformed request body — missing 'key' field returns validation error","Insufficient funds in calling wallet — x402 payment rejected","Network/gateway timeout — payment state unknown, may require idempotency check"],"whenToPreferThis":"Use this endpoint when an AI agent or developer holds an MCP Gateway API key and needs to pre-fund it with USDC to unlock access to the 58 bundled tools (DeFi, Weather, Security, Domain, Intelligence, etc.) without integrating per-call wallet payment. Prefer this over direct x402 per-call payment when the agent will make multiple downstream tool calls and wants a simpler credential-based flow.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T18:36:57.225Z","isFirstParty":false}