crosscheck
REMOTE · CROSSCHECKAPI.COM · 2 COMPONENTS · SCANNED SEP 26
Checks for AI agents over x402: review drafts, accept-check handoffs, scan skills before install.
Available components
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 6 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 Usability64
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 1301 tokens (~216/item across 6 items; 6 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management3
- Stability observed for 1 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage99
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 96% 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 6 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 7 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities60
- Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28. See how to fix → Fail
How do I install the crosscheck MCP server?
crosscheck is a hosted endpoint at https://crosscheckapi.com/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 · crosscheckapi.com
claude mcp add --transport http com-crosscheckapi-crosscheck 'https://crosscheckapi.com/mcp'
{
"mcpServers": {
"com-crosscheckapi-crosscheck": {
"url": "https://crosscheckapi.com/mcp"
}
}
} {
"servers": {
"com-crosscheckapi-crosscheck": {
"type": "http",
"url": "https://crosscheckapi.com/mcp"
}
}
} [mcp_servers.com-crosscheckapi-crosscheck] url = "https://crosscheckapi.com/mcp"
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"com-crosscheckapi-crosscheck": {
"type": "remote",
"url": "https://crosscheckapi.com/mcp",
"enabled": true
}
}
} openclaw mcp add com-crosscheckapi-crosscheck --url 'https://crosscheckapi.com/mcp' --transport streamable-http
mcp_servers:
com-crosscheckapi-crosscheck:
url: "https://crosscheckapi.com/mcp" {
"McpServers": {
"com-crosscheckapi-crosscheck": {
"Transport": "http",
"Url": "https://crosscheckapi.com/mcp"
}
}
} assistant mcp add com-crosscheckapi-crosscheck -t streamable-http -u 'https://crosscheckapi.com/mcp'
{
"mcpServers": {
"com-crosscheckapi-crosscheck": {
"type": "http",
"url": "https://crosscheckapi.com/mcp"
}
}
} The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.
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.
- 26 Sept 26 0
- Schema quality: 194 → 216 ▼ functional
- Stability: unverified → 0.03 ▲ functional
- New tool “verify_receipt” functional
- “check” added an optional parameter “open_review” cosmetic
- “check” added an optional parameter “moltbook_identity” cosmetic
- 25 Sept 26 57
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 26 Sept 2026 · Probed https://crosscheckapi.com/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=crosscheckapi.com | CN=YE1,O=Let's Encrypt,C=US | 23 Sept 2026 | 22 Dec 2026 | ECDSA 256 | ECDSA-SHA384 | 5a8843513c307f46d596732d38fb129d906 |
| SANs: *.crosscheckapi.com, crosscheckapi.com | ||||||
| CN=YE1,O=Let's Encrypt,C=US (CA) | CN=Root YE,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | ECDSA 384 | ECDSA-SHA384 | 5ddd70dd31f801c85c186a7a04b80afe |
| 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 crosscheckapi.com. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| com. | present | 19718 | 13 | Verified |
| crosscheckapi.com. | 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://crosscheckapi.com/mcp | Verified | 200 | |
| http (plaintext) | http://crosscheckapi.com/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 →
accept Check a deliverable against its task ~269
Checks work another agent handed back against the task it was given, before you pay, release escrow, or pass it on. Returns accept, reject, or verify_externally with every requirement judged; counts, required JSON fields, and sums are checked in code. Optional payment_tx is verified on chain. $0.03 base. Paid per call in USDC over x402 (Base, or free test USDC on Base Sepolia). An x402-aware MCP client pays automatically: the first call returns the price as an x402 PaymentRequired error, and the retry carries the payment in _meta["x402/payment"]. Without one, use the npm client `npx -y crosscheckapi`, which pays from a wallet you set.
| Name | Type | Req | Description |
|---|---|---|---|
| deliverable | string | yes | What came back |
| payment_network | string | – | Network of payment_tx, for example eip155:8453 |
| payment_tx | string | – | Optional transaction hash of the payment for this work |
| ref | string | – | Optional: the hash of a crosscheck receipt that brought you here. Its wallet earns check credits from your first 90 days of spend. |
| reference | string | – | Optional reference material the task points to |
| task | string | yes | The task as given to the other agent |
No output schema declared.
No examples provided.
check Review a draft ~297
Independent review of a draft (email, report, summary, PR description) before its human sees it. Returns pass or specific issues with fixes; arithmetic is recomputed in code. With sources, each claim is checked against them and quotes are verified. $0.02. Paid per call in USDC over x402 (Base, or free test USDC on Base Sepolia). An x402-aware MCP client pays automatically: the first call returns the price as an x402 PaymentRequired error, and the retry carries the payment in _meta["x402/payment"]. Without one, use the npm client `npx -y crosscheckapi`, which pays from a wallet you set.
| Name | Type | Req | Description |
|---|---|---|---|
| draft | string | yes | The draft text to review |
| moltbook_identity | string | – | Optional: a Moltbook identity token for the free tier, when it is on (a verified Moltbook agent gets free checks with no payment). Not stored. Without a free check left, the price comes back as usual |
| open_review | boolean | – | Optional: let a qualified outside reviewer take the job (not routed yet; crosscheck's reviewer does it and the receipt says so) |
| ref | string | – | Optional: the hash of a crosscheck receipt that brought you here. Its wallet earns check credits from your first 90 days of spend. |
| sources | array | – | Optional texts the draft relies on; turns on grounding |
No output schema declared.
No examples provided.
result Get a result ~64
Free. Status, verdict, and signed receipt of an earlier paid call that was still running, using the job_id and result_token it returned.
| Name | Type | Req | Description |
|---|---|---|---|
| job_id | string | yes | job_id from the paid call |
| result_token | string | yes | result_token from the paid call |
No output schema declared.
No examples provided.
skillcheck Security review of a skill or MCP server ~220
Security review of a skill or MCP server's files before you install or connect it: read, never run. Free when these exact files were scanned before (looked up by bundle hash); otherwise paid, $0.03 base. Never says safe. Paid per call in USDC over x402 (Base, or free test USDC on Base Sepolia). An x402-aware MCP client pays automatically: the first call returns the price as an x402 PaymentRequired error, and the retry carries the payment in _meta["x402/payment"]. Without one, use the npm client `npx -y crosscheckapi`, which pays from a wallet you set.
| Name | Type | Req | Description |
|---|---|---|---|
| files | array | yes | Every text file of the skill or server, docs included; code rules read all of them |
| fresh | boolean | – | Scan again even when a past scan of these exact files exists |
| ref | string | – | Optional: the hash of a crosscheck receipt that brought you here. Its wallet earns check credits from your first 90 days of spend. |
No output schema declared.
No examples provided.
skillcheck_lookup Look up a past skillcheck ~58
Free. The latest skillcheck of an exact bundle, by its bundle_sha256 (SHA-256 of the canonical JSON of the files sorted by path, each as {path, sha256}).
| Name | Type | Req | Description |
|---|---|---|---|
| bundle_sha256 | string | yes | – |
No output schema declared.
No examples provided.
verify_receipt Verify a crosscheck receipt ~241
Free. Before trusting work that arrives with a crosscheck receipt, check in code that crosscheck issued it, its signature is valid, what the outcome was, and that it covers exactly the text you were handed. Pass receipt_hash (or the receipt object) plus that text: draft and sources for check, task and deliverable for accept, files for skillcheck, and the verdict if one came with it.
| Name | Type | Req | Description |
|---|---|---|---|
| deliverable | string | – | accept: the deliverable the receipt should cover |
| draft | string | – | check: the draft the receipt should cover |
| files | array | – | skillcheck: the skill's files |
| receipt | object | – | Or the whole receipt object {body, hash, sig} |
| receipt_hash | string | – | The receipt's hash (the last part of its /r/ proof link) |
| sources | array | – | check: the sources, if the check had any, in the same order (strings or {text}) |
| task | string | – | accept: the task the receipt should cover |
| verdict | object | – | The verdict that came with the receipt, to confirm nobody edited it |
No output schema declared.
No examples provided.
What is the crosscheck MCP server?
crosscheck is an MCP server listed in the public MCP registry as com.crosscheckapi/crosscheck. Checks for AI agents over x402: review drafts, accept-check handoffs, scan skills before install. This page covers its hosted endpoint (https://crosscheckapi.com/mcp).
Is the crosscheck MCP server safe to use?
crosscheck scores 57 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 crosscheck MCP server expose?
crosscheck exposes 6 tools: check, accept, skillcheck, skillcheck_lookup, verify_receipt, result. Their descriptions and schemas cost roughly 1,149 tokens of context every time the server is loaded.
Does the crosscheck MCP server require authentication?
No. We connected to crosscheck without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the crosscheck MCP server still maintained?
crosscheck is still listed as active in the MCP registry. We last reached this channel on 26 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.