ProofCheck
REMOTE · PROOFCHECK.SOMETHING-AGENT.WORKERS.DEV
Free x402 offer/receipt checker: verifies signatures and whether the signer fits the host.
Available components
Last scanned (7 minutes ago)
Scores higher than 43% of remote servers
Reachable. Last reached 5 Nov 2026.
Category Crypto and Web3
How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →
Endpoint Security46
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- Authorisation not fully verified: no authorisation is required to call this server, and 5 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe. See how to fix → View diagnostics → Unverified
- HTTPS enforcement could not be verified: the plaintext port answered with HTTP 405, which proves neither a plaintext path nor enforcement. View diagnostics → Unverified
- HSTS check failed: the Strict-Transport-Security header is absent. See how to fix → View diagnostics → Fail
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability62
- AI-judged instruction clarity (fair).Partial
- Tool/resource definitions use about 448 tokens (~89/item across 5 items; 5 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management30
- Stability observed for 9 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage73
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 18% of tool parameters carry a description.Partial
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 5 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 6 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 5 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 27 to 30. That category is still filling its 30-day observation window: 8 days of observed history at the previous scan, 9 at this one. The score rises as the window fills, whether or not the server changes.
- 3 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 20 to 23. That category is still filling its 30-day observation window: 6 days of observed history at the previous scan, 7 at this one. The score rises as the window fills, whether or not the server changes.
- 1 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 13 to 17. That category is still filling its 30-day observation window: 4 days of observed history at the previous scan, 5 at this one. The score rises as the window fills, whether or not the server changes.
- 30 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 7 to 10. That category is still filling its 30-day observation window: 2 days of observed history at the previous scan, 3 at this one. The score rises as the window fills, whether or not the server changes.
- 28 Oct 26 +1
- Stability: unverified → 0.03 ▲ functional
- Server version: 0.1.0 → 0.1.4 functional
- 27 Oct 26 55
First indexed and scored.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 5 Nov 2026 · Probed https://proofcheck.something-agent.workers.dev/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=something-agent.workers.dev | CN=YE2,O=Let's Encrypt,C=US | 22 Oct 2026 | 20 Jan 2027 | ECDSA 256 | ECDSA-SHA384 | 6f8d01b3f27f434c2bca9afbc694019e867 |
| SANs: *.something-agent.workers.dev, something-agent.workers.dev | ||||||
| CN=YE2,O=Let's Encrypt,C=US (CA) | CN=Root YE,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | ECDSA 384 | ECDSA-SHA384 | 4df3b15dd6c0784c507cd37b58e6f115 |
| CN=Root YE,O=ISRG,C=US (CA) | CN=ISRG Root X2,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | ECDSA-SHA384 | 872165fc34b6e5fba8add5b3705fb53a |
| CN=ISRG Root X2,O=Internet Security Research Group,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | SHA256-RSA | 6c8f1dc727c7117f7baf853ac980f9cd |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of proofcheck.something-agent.workers.dev. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| dev. | present | 60074 | 8 | Verified |
| workers.dev. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://proofcheck.something-agent.workers.dev/mcp | Verified | 200 | |
| http (plaintext) | http://proofcheck.something-agent.workers.dev/mcp | Inconclusive | 405 |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
lookup_erc8004_agent ~79
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.
| Name | Type | Req | Description |
|---|---|---|---|
| agent_id | string | yes | – |
| chain_id | integer | yes | – |
No output schema declared.
No examples provided.
preflight_x402_endpoint ~66
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.
| Name | Type | Req | Description |
|---|---|---|---|
| method | string | – | – |
| url | string | yes | – |
No output schema declared.
No examples provided.
verify_offer ~110
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.
| Name | Type | Req | Description |
|---|---|---|---|
| accepts | array | – | Optional accepts[] from the live 402 to match against |
| offer | object | yes | The offer object: {format, payload?, signature, acceptIndex?} |
| resource_url | string | – | – |
| trusted_pay_to | array | – | – |
No output schema declared.
No examples provided.
verify_payment_required ~58
Verify every signed offer inside a PaymentRequired object (pass the decoded JSON, or the raw base64 PAYMENT-REQUIRED header). Free.
| Name | Type | Req | Description |
|---|---|---|---|
| payment_required | – | yes | Object or base64/JSON string |
| resource_url | string | – | – |
No output schema declared.
No examples provided.
verify_receipt ~101
Verify an x402 signed receipt (EIP-712 or JWS) returned in the settlement response: signature, freshness, payer/resource/transaction match, signer-authorization evidence. Free.
| Name | Type | Req | Description |
|---|---|---|---|
| max_age_seconds | number | – | – |
| network | string | – | – |
| payer | string | – | – |
| receipt | object | yes | – |
| resource_url | string | – | – |
| transaction | string | – | – |
| trusted_pay_to | array | – | – |
No output schema declared.
No examples provided.
How do I install the ProofCheck MCP server?
ProofCheck is a hosted endpoint at https://proofcheck.something-agent.workers.dev/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
remote · proofcheck.something-agent.workers.dev
claude mcp add --transport http something-agent-proofcheck 'https://proofcheck.something-agent.workers.dev/mcp'
What is the ProofCheck MCP server?
ProofCheck is an MCP server listed in the public MCP registry as io.github.something-agent/proofcheck. Free x402 offer/receipt checker: verifies signatures and whether the signer fits the host. This page covers its hosted endpoint (https://proofcheck.something-agent.workers.dev/mcp).
Is the ProofCheck MCP server safe to use?
ProofCheck scores 60 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the ProofCheck MCP server expose?
ProofCheck exposes 5 tools: verify_offer, verify_receipt, verify_payment_required, preflight_x402_endpoint, lookup_erc8004_agent. Their descriptions and schemas cost roughly 414 tokens of context every time the server is loaded.
Does the ProofCheck MCP server require authentication?
No. We connected to ProofCheck without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the ProofCheck MCP server still maintained?
ProofCheck is still listed as active in the MCP registry. We last reached this channel on 5 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.