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x402 Doctor

Is this x402/MPP API safe to pay?

Connector by Fizzl13 · GitHub account verified by the MCP Registry

IndexedAGPL-3.0Remote (HTTP)★ 1
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Install

Works with Claude Code, VS Code, Cursor, Windsurf. Read the repository before you give any tool access to your data.

npx agentmarket install connector/fizzl13-x402-doctor

Asks which of your tools to add it to (Claude Code, Codex, Cursor, VS Code, Windsurf, Gemini CLI, Claude Desktop) and shows the change first. See https://agentmart.dev/cli.

Remote endpoint

  • https://x402-doctor.fizzl.eu/mcp Remote (HTTP)

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About

Is this x402/MPP API safe to pay? $0.001 preflight, fixes, a $0.25 test purchase. Free quick check.

No reviews yet. Installed it? Reviews come from verified installers only. How reviews work

Permissions

What this server can do and what it asks for, from its tool list, install config and code. Checked Oct 26, 2026.

Tools
10 read · 3 write · 0 delete
Secrets
None asked for
Install scripts
Nothing to install (hosted)
Runs as
Hosted (remote endpoint)

Tools by what they do 13

From the running server's own tool list (tools/list) on Oct 25, 2026.

Read 10 · Look things up without changing anything.

  • check_payment_proof
  • verify_receipt
  • x402_delivery_status
  • x402_diagnose
  • x402_fix
  • x402_preflight
  • x402_preflight_batch
  • x402_preflight_deep
  • x402_quick_check
  • x402_trust_record

Write 3 · Create, change, send or run things.

  • feedback
  • x402_delivery_check
  • x402_trust_add

Network hosts it talks to 60

  • ai.fizzl.eu · found in code
  • api.anthropic.com · found in code
  • api.avax.network · found in code
  • api.cdp.coinbase.com · found in code
  • api.circle.com · found in code
  • api.companyfacts.ai · found in code
  • api.devnet.solana.com · found in code
  • api.github.com · found in code
  • api.indexnow.org · found in code
  • api.mainnet-beta.solana.com · found in code
  • api.tokenquotes.io · found in code
  • api.toolhub.dev · found in code
  • api.typesafe.ai · found in code
  • api.weatherfeed402.com · found in code
  • app.uniswap.org · found in code
  • arb1.arbitrum.io · found in code
  • arbiscan.io · found in code
  • atlas.fizzl.eu · found in code
  • base-rpc.publicnode.com · found in code
  • basescan.org · found in code
  • bsc-dataseed.bnbchain.org · found in code
  • buy.fizzl.eu · found in code
  • cdn.jsdelivr.net · found in code
  • channels.openzeppelin.com · found in code
  • cv.fizzl.eu · found in code
  • dapp-scanning.api.cx.metamask.io · found in code
  • data.marketpulse.ai · found in code
  • eips.ethereum.org · found in code
  • facilitator.goplausible.xyz · found in code
  • facilitator.payai.network · found in code
Show 30 more hosts
  • fizzl.eu · found in code
  • fonts.googleapis.com · found in code
  • github.com · found in code
  • glama.ai · found in code
  • horizon-testnet.stellar.org · found in code
  • horizon.stellar.org · found in code
  • huggingface.co · found in code
  • ichimoku-signal.fizzl.eu · found in code
  • ichimoku-signal.onrender.com · found in code
  • lab.fizzl.eu · found in code
  • mainnet-api.algonode.cloud · found in code
  • mainnet.base.org · found in code
  • mainnet.optimism.io · found in code
  • metamask-verify-wallet.com · found in code
  • mpp.dev · found in code
  • myfarmgame.net · found in code
  • optimistic.etherscan.io · found in code
  • paymentauth.org · found in code
  • pg1-ai-agent.vercel.app · found in code
  • plaintext.fizzl.eu · found in code
  • polygon-rpc.com · found in code
  • polygonscan.com · found in code
  • presign-guard.fizzl.eu · found in code
  • presign-guard.onrender.com · found in code
  • projects.fizzl.eu · found in code
  • raw.githubusercontent.com · found in code
  • solscan.io · found in code
  • wallet.fizzl.eu · found in code
  • x402-doctor.fizzl.eu · found in remote endpoint, install command, code
  • xrplcluster.com · found in code

Tools (13)

As the server listed them on Oct 25, 2026. Descriptions are the server’s own words; hidden characters are shown as [U+…].

  • check_payment_proofCheck an x402 payment proof (free)read-only

    Free: after paying an x402 endpoint, pass the PAYMENT-RESPONSE header it returned (X-PAYMENT-RESPONSE in v1). Returns the transaction, network and payer it names, whether that transaction exists on-chain and succeeded, and which USDC moved from whom to whom, with an explorer link. Read-only. Limited to 10 calls per hour.

  • feedbackSend feedback (free)

    Report a bug, a missing feature or anything else about this service, in a structured way. Free. A person reads every report; nothing is run or changed automatically.

  • verify_receiptVerify a signed x402 Doctor answer (free)read-only

    Free: check the signed receipt that every paid x402 Doctor answer carries (diagnose, preflight, batch, deep, fix, delivery check; HTTP or MCP), for example to prove later which verdict you got before paying an endpoint. Pass the whole answer as response. Returns valid, the signer and whether it is an x402 Doctor signer; with route and input also whether the receipt is for exactly that request. A changed verdict or receipt fails. Read-only, nothing is stored. Same as POST /api/v1/verify.

  • x402_delivery_checkHave an x402 endpoint bought once: paid and delivered? ($0.25 via x402)

    Paid ($0.25 via x402 in USDC on Base, Solana, Algorand or Stellar, or in RLUSD on the XRP Ledger): not a reading but a purchase. x402 Doctor buys the endpoint once (at most $0.1, USDC on Base, from its own wallet) with the example input its listing declares, checks the answer against the declared output schema, has TypeSafe's Jev judge whether it is what was paid for, and measures the charge on chain. Answers with a job id at once; follow it with x402_delivery_status (free), the result usually comes within minutes. The endpoint must get a "go" from the pre-payment check and be payable in USDC …

  • x402_delivery_statusStatus of a delivery check (free)read-only

    Free: the status of a delivery check ordered with x402_delivery_check (or GET /api/v1/delivery-check): awaiting_payment, queued or done, and once done the result: paid_and_delivered, the outcome, the charge measured on chain and the transaction.

  • x402_diagnoseDiagnose an x402 endpoint ($0.01 via x402)read-only

    Paid ($0.01 via x402 in USDC on Base, Solana, Algorand or Stellar, or in RLUSD on the XRP Ledger): diagnose an x402 endpoint the way a paying agent would, without paying it: the 402 challenge format, every accepts[] option, the resource URL, Solana settlement readiness, which wallets can pay, Bazaar/OpenAPI discovery and the browser paywall. Returns every check with pass/warn/fail and a fix hint. For the endpoint's owner or a developer debugging it; to decide whether to pay someone else's endpoint, use x402_preflight. Same as GET /api/v1/diagnose. The answer carries a signed receipt (EIP-191, …

  • x402_fixFix plan for an x402 endpoint ($0.05 via x402)read-only

    Paid ($0.05 via x402 in USDC on Base, Solana, Algorand or Stellar, or in RLUSD on the XRP Ledger): diagnoses your x402 endpoint, then returns per problem the concrete change as code for your stack (express, next, hono, node, python, generic), filled in with your own payTo, amount, network and route. For the endpoint's owner: includes the diagnosis, so there is no need to call x402_diagnose first. Same as GET /api/v1/fix. The answer carries a signed receipt (EIP-191, bound to your arguments) that proves later which verdict you got.

  • x402_preflightCheck an x402 endpoint before paying it ($0.001 via x402)read-only

    Paid ($0.001 via x402 in USDC on Base, Solana, Algorand or Stellar, or in RLUSD on the XRP Ledger): call this before your agent pays an x402 endpoint. Returns go, caution or no_go, the recommended payment option, and why: payment would fail, the seller's payout address is on the OFAC SDN sanctions list, over your budget (max_usd), price above what is advertised, not HTTPS, unknown token, its 30-day track record. Never pays the endpoint. The buyer's check for one call; for several endpoints at once use x402_preflight_batch, before a payment above about $1 x402_preflight_deep, and to debug your …

  • x402_preflight_batchCheck up to 10 x402 endpoints before paying ($0.005 via x402)read-only

    Paid ($0.005 via x402 in USDC on Base, Solana, Algorand or Stellar, or in RLUSD on the XRP Ledger): the pre-payment check for up to 10 x402 endpoints at once. Per endpoint go, caution or no_go, the recommended payment option and why, plus totals. For marketplaces and agents that weigh several services. Never pays the endpoints. Same as GET /api/v1/preflight/batch. The answer carries a signed receipt (EIP-191, bound to your arguments) that proves later which verdict you got.

  • x402_preflight_deepDeep check of an x402 endpoint before an expensive payment ($0.01 via x402)read-only

    Paid ($0.01 via x402 in USDC on Base, Solana, Algorand or Stellar, or in RLUSD on the XRP Ledger): for expensive calls. The pre-payment verdict (go, caution or no_go) plus the full diagnosis, the 30-day history per day, how reliable the seller's other endpoints are and whether the endpoint moved domains. Never pays the endpoint. Worth it before a payment above about $1; for an ordinary call x402_preflight is enough. Same as GET /api/v1/preflight/deep. The answer carries a signed receipt (EIP-191, bound to your arguments) that proves later which verdict you got.

  • x402_quick_checkQuick x402 endpoint check (free)read-only

    Free: does this x402 endpoint work for a paying agent? Returns pass, warn or fail with the number of problems and the top three. Limited to 10 calls per hour. For every check use x402_diagnose ($0.01); for code changes x402_fix ($0.05); before paying someone else's endpoint x402_preflight ($0.001).

  • x402_trust_addAdd your endpoint to the x402 Trust Index (free)

    Free: add your own paid endpoint to the x402 Trust Index when no registry lists it yet (CDP Bazaar, Circle's Agent Marketplace, GoPlausible, XRPL AI Hub, MPP directory). x402 Doctor first checks that it answers 402 with a payment challenge (x402, MPP or L402); the next daily scan starts its record, which buyers' agents see before they pay. At most 25 endpoints per host. Limited to 10 calls per hour.

  • x402_trust_recordx402 Trust Index record (free)read-only

    Free: the daily track record of a paid x402 or MPP endpoint from the x402 Trust Index: on how many of the last 30 scanned days an agent could pay it, the latest verdict and reasons, price and networks. found: false when it is not in the index; add your own endpoint with x402_trust_add. Limited to 10 calls per hour. Before paying, x402_preflight ($0.001) checks the live 402 and includes this record.

Signals

Stars
1
Forks
0
Open issues
2
Last commit
Oct 24, 2026 (5 days ago)
Last release
Oct 12, 2026 (16 days ago)

From GitHub (fetched Oct 24, 2026).

Details

Registry name
io.github.Fizzl13/x402-doctor
Version
1.0.3
Auth
Auth not stated
License
AGPL-3.0
First seen
Oct 24, 2026
Last checked
Oct 24, 2026

More from Fizzl13

Cite this page

x402 Doctor MCP server. Agent Mart. https://agentmart.dev/connectors/fizzl13-x402-doctor (last updated 2026-10-24)