Spec Driven Development
MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.
Description from the maker (original English)
Checks for AI agents over x402: review drafts, accept-check handoffs, scan skills before install.
These three are never merged into one score: opinions, measurements and popularity are different things.
We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
Pick the AI app you use, then copy the settings.
CROSSCHECK_WALLET_KEY, CROSSCHECK_MAX_USD, CROSSCHECK_NETWORKSValues marked secret are keys to your account. Never share them or paste them into a chat.
You need
Which app do you use?
Pick your app above. We remember it, so next time the button says “Install in …”.
Works in Claude on the web, desktop and mobile:
https://crosscheckapi.com/mcpOpen Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json
{
"mcpServers": {
"crosscheck": {
"command": "npx",
"args": [
"-y",
"crosscheckapi"
],
"env": {
"CROSSCHECK_WALLET_KEY": "your-value",
"CROSSCHECK_MAX_USD": "your-value",
"CROSSCHECK_NETWORKS": "your-value"
}
}
}
}Run this in your terminal
claude mcp add --transport http crosscheck https://crosscheckapi.com/mcpclaude mcp add crosscheck --env CROSSCHECK_WALLET_KEY=your-value --env CROSSCHECK_MAX_USD=your-value --env CROSSCHECK_NETWORKS=your-value -- npx -y crosscheckapiFill in the empty values before running it.
Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"crosscheck": {
"url": "https://crosscheckapi.com/mcp"
}
}
}Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"crosscheck": {
"command": "npx",
"args": [
"-y",
"crosscheckapi"
],
"env": {
"CROSSCHECK_WALLET_KEY": "your-value",
"CROSSCHECK_MAX_USD": "your-value",
"CROSSCHECK_NETWORKS": "your-value"
}
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
Paste into .vscode/mcp.json in your project
{
"servers": {
"crosscheck": {
"type": "http",
"url": "https://crosscheckapi.com/mcp"
}
}
}Paste into .vscode/mcp.json in your project
{
"servers": {
"crosscheck": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"crosscheckapi"
],
"env": {
"CROSSCHECK_WALLET_KEY": "your-value",
"CROSSCHECK_MAX_USD": "your-value",
"CROSSCHECK_NETWORKS": "your-value"
}
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
ChatGPT connects only to servers on the internet:
https://crosscheckapi.com/mcpMenu names can differ slightly by plan and over time.
Your choice stays on this device in a cookie; no account needed.
CROSSCHECK_MAX_USD envCROSSCHECK_NETWORKS envThese settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
Tool names and descriptions exactly as the server reported them on Nov 7, 2026. The maker wrote them, not us; we show them as plain text.
checkIndependent 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 request (what the human asked), it also checks the draft answers that. With sources, each claim is c
acceptChecks 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 verif
skillcheckSecurity 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
sellercheckFor x402 sellers: one dated report on your own paid resource, by code alone. Does it answer a valid 402 (v1 or v2: price, network, payTo), is it in the x402 Bazaar index, would agent402's router route to it, and how many USDC settlements reached its payTo on Base in 24 hours and
sellerwatchFor x402 sellers: sellercheck every hour for 30 days on one resource, paid once. An alert to your webhook (JSON POST) or ntfy topic only when something changes: the 402 breaks or its price or payTo change, it leaves or rejoins the Bazaar index, agent402's router flips, settlement
skillcheck_lookupFree. 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}).
verify_receiptFree. 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, request,
resultFree. Status, verdict, and signed receipt of an earlier paid call that was still running, using the job_id and result_token it returned.
We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026
The publisher (crosscheckapi.com) is not the repo owner (maxugc); someone else may have listed it
We have not read this repo from GitHub yet
We have not read this repo from GitHub yet
Responded in 202 ms (HTTP 200)
No sign-in needed
Read 8 tool descriptions and found no hidden instructions to the AI
Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.
It passed 2 of 3 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.
You need to fill in: CROSSCHECK_WALLET_KEY
Either way works: install it on your computer or connect to the cloud version.
The GitHub repo last changed –, and the latest version (0.6.0) reached the registry 14 days ago.
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.
In the same category: Spec Driven Development, Remote Desktop Commander, Signoff
Servers in the same category from other makers, sorted by stars.
Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.
Remote Desktop Commander: use files, terminal and processes on your own computers from any AI app.
Five gates that make an agent's 'done' provable: run them, read the verdict, audit the record.
Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.
An independent second opinion on a draft before your human sees it.
Your agent sends the text it wrote: an email, report, message, PR description, or summary. crosscheck returns a JSON verdict, either pass or a list of specific issues with fixes, plus an Ed25519-signed receipt. It catches wrong arithmetic (checked in code, not by the model), contradictions, leftover placeholders, leaked secrets, unauthorized commitments, and prompt injection. Each check costs $0.02 in USDC on Base for up to 12,000 units (one per English character), paid per request over x402. There is no account and no API key.
To try it without real money, pay with test USDC on Base Sepolia (free at https://faucet.circle.com) and set
CROSSCHECK_NETWORKS=eip155:84532.
{
"mcpServers": { "crosscheck": { "command": "npx", "args": ["-y", "crosscheckapi"], "env": { "CROSSCHECK_WALLET_KEY": "0x " } } } }
Tools:
quote: free. The price for a draft, and whether checks are available now.order: pays the quoted price and returns the verdict and signed receipt. Pass moltbook_identity to use a free check if you are a verified Moltbook agent. Optional: request (what your human asked, word for word; the draft fails if it answers a different question or leaves part out), sources (text the draft relies on), source_urls (up to 3 pages crosscheck opens and checks the draft against, +$0.01 each), and fetch_cited (also open the draft's own links).accept: pays about $0.03 and checks work another agent or service handed back against the task you gave it. Returns accept or reject with each requirement judged, before you pay for the work or pass it on.skillcheck: security-checks a skill or MCP server folder before you install it. Free when someone already scanned the same files, otherwise about $0.03.result: free. Status, verdict, and receipt of an earlier order.npx -p crosscheckapi crosscheck quote draft.txt
npx -p crosscheckapi crosscheck order draft.txt npx -p crosscheckapi crosscheck accept task.txt deliverable.txt npx -p crosscheckapi crosscheck skillcheck ./some-skill npx -p crosscheckapi crosscheck result npx -p crosscheckapi crosscheck credits [wallet] npx -p crosscheckapi crosscheck order draft.txt --request "What will 12 seats cost per year?" --url https://example.com/pricing
The draft is read from the file, or from stdin if no file is given. Output is JSON.
Referrals: the paid commands (order, accept, skillcheck) take --ref , the id in a crosscheck proof link (/r/ ) that led you here. When your wallet's first check paid in real USDC carries a ref, the wallet behind that receipt earns check credits worth 20% of what you pay for 90 days; it costs you nothing. --credits pays with your own wallet's referral credits by signing a credit order instead of paying, and falls back to USDC only when the credits do not cover the price. crosscheck credits shows your balance. The MCP tools take the same options as ref and credits, and add a free credits tool.
| Variable | Meaning |
|---|---|
CROSSCHECK_WALLET_KEY | Private key of the wallet that pays. Use a dedicated wallet holding a few dollars, never your main wallet. Only needed for paid orders. |
CROSSCHECK_MAX_USD | Refuse to pay more than this per check. Default 0.10. |
CROSSCHECK_URL | Service URL. Default https://crosscheckapi.com. |
CROSSCHECK_NETWORKS | Networks the client may pay on, in order of preference. Default eip155:8453,eip155:84532 (Base, then Base Sepolia). Set eip155:84532 to use test USDC only. |
Every paid check returns receipt with body, hash, and sig. The client verifies it automatically against the public key at https://crosscheckapi.com/.well-known/crosscheck-keys.json and reports receipt_check.valid. The receipt covers a SHA-256 of your draft (never the text), the payment, and a SHA-256 of the verdict, and it is chained into an append-only ledger.
The draft is sent to crosscheck and to its review model, then deleted when the check finishes. Only its hash is kept. Do not send text your human has marked confidential.
Source, examples for Claude Code, Cursor, VS Code, OpenAI Agents SDK, LangChain, and more: https://github.com/maxugc/crosscheck
Service summary for agents: https://crosscheckapi.com/llms.txt