ProofCheck
io.github.something-agent/proofchecksomething-agentstreamable-httpv0.1.0Scanned
Free x402 offer/receipt checker: verifies signatures and whether the signer fits the host.
5 tools: 1 do something that can't be undone, 3 change things and 1 only read.
- Reads private data · 1
- Reads text others write · 0
- Can send data out · 1
- No findings
Anlyon alternative
4 of these tools change something. Run those as governed actions.
Declare what an action changes, and Anlyon puts it under a shared limit, binds every approval to the exact request, and grades the outcome. It works on any HTTPS API you can describe as an action.
Anlyon does not run, proxy or govern this MCP server. A tool your own code calls directly is not routed through Anlyon and is not governed by it.
Import an OpenAPI spec →Tools
Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.
5 tools
Can't be undone 1Claude Code: ask
verify_payment_requiredVerify every signed offer inside a PaymentRequired object (pass the decoded JSON, or the raw base64 PAYMENT-REQUIRED header).No findings
Why it is in this group
- The name "verify_payment_required" says "payment": a word that usually means money moves, which cannot be taken back.
Description, as the server wrote it Verify every signed offer inside a PaymentRequired object (pass the decoded JSON, or the raw base64 PAYMENT-REQUIRED header). Free.
Changes things 3Claude Code: ask
preflight_x402_endpointUnpaid preflight of an x402 URL: fetch its 402, summarise accepts[]/extensions, verify any signed offers and report who can vouch for the signer.Can send data outNo findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
What it can reach
- outboundThe input takes a URL (input.url): a request to a URL can carry data to whoever runs it.
Description, as the server wrote it Unpaid preflight of an x402 URL: fetch its 402, summarise accepts[]/extensions, verify any signed offers and report who can vouch for the signer. Never pays. Free.
verify_offerVerify an x402 signed offer (EIP-712 or JWS): signature, expiry, match to accepts[], and signer-authorization evidence (payTo, did:web, DNS _controllers, ERC-8004).No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
Description, as the server wrote it Verify an x402 signed offer (EIP-712 or JWS): signature, expiry, match to accepts[], and signer-authorization evidence (payTo, did:web, DNS _controllers, ERC-8004). Free.
verify_receiptVerify an x402 signed receipt (EIP-712 or JWS) returned in the settlement response: signature, freshness, payer/resource/transaction match, signer-authorization evidence.No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
Description, as the server wrote it Verify an x402 signed receipt (EIP-712 or JWS) returned in the settlement response: signature, freshness, payer/resource/transaction match, signer-authorization evidence. Free.
Only reads 1Show 1 read-only tool
lookup_erc8004_agentRead-only ERC-8004 identity lookup (owner, agentWallet, registration file, endpoint-domain verification) on Ethereum, Base, Optimism, Arbitrum, Polygon, BNB, Avalanche, Gnosis, Cel…Reads private dataNo findings
Why it is in this group
- The name "lookup_erc8004_agent" says "lookup": a word for reading.
What it can reach
- private-dataThe description's first sentence says "read" and "file": it reads files.
Description, as the server wrote it Read-only ERC-8004 identity lookup (owner, agentWallet, registration file, endpoint-domain verification) on Ethereum, Base, Optimism, Arbitrum, Polygon, BNB, Avalanche, Gnosis, Celo, Linea or Scroll.
This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.
Exfil surface
Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.
No private-data, untrusted-input, outbound path in this server alone: no tool is tagged untrusted-input.
- Reads private data1
- Reads files, mail, messages, databases, secrets, calendars or repositories.
- Reads text others write0
- Brings in text someone else can write: web pages, inbound email, messages, issues and comments.
- Can send data out1
- Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.
Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.
Findings
Matches of fixed checks, with the text they matched.
No check matched anything in these tool definitions. That is not a safety guarantee.
History
Changes to its tool definitions and to its remote endpoint, newest first.
No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.
Install
Pinned to version 0.1.0. Values in angle brackets are yours to fill in.
claude mcp add --transport http proofcheck https://proofcheck.something-agent.workers.dev/mcpclaude mcp add --transport http proofcheck https://proofcheck.something-agent.workers.dev/mcpRun in a terminal.
Claude Code permissions
Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.
{
"permissions": {
"allow": [
"mcp__proofcheck__lookup_erc8004_agent"
],
"ask": [
"mcp__proofcheck__verify_offer",
"mcp__proofcheck__verify_receipt",
"mcp__proofcheck__verify_payment_required",
"mcp__proofcheck__preflight_x402_endpoint"
],
"deny": []
}
}Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as proofcheck. Review it before you use it.
Capability tags behind 2 rules
- mcp__proofcheck__preflight_x402_endpoint outbound
- mcp__proofcheck__lookup_erc8004_agent private-data
Pin
Keep the decision: fail CI when the tools change, follow every change, or show a badge.
Pin in CI
Fail a build when the tools you reviewed are not the tools the server serves today.
curl -s "https://anlyon.dev/api/v1/servers/io.github.something-agent/proofcheck/verify?hash=7416d7afa08c7e57723536f43f3a7143a5bc119a33e88ac80843626219f527f4" | jq -e '.changed == false'Pinned hash 7416d7afa08c, from Oct 27, 2026, 17:18 UTC.
Watch
Get told when its tools change: a new tool, a new description, a new class.
https://anlyon.dev/servers/io.github.something-agent/proofcheck/changes.xmlAn Atom feed. Works in any feed reader or Slack's RSS app.
Badge
[](https://anlyon.dev/servers/io.github.something-agent/proofcheck)Source: MCP Registry · repository. Synced Oct 27, 2026, 17:18 UTC.