Spec Driven Development
MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.
Description from the maker (original English)
Verify code402 XDR-1 receipts: keccak digest + secp256k1 signer recovery. Free, stateless.
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We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
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Works in Claude on the web, desktop and mobile:
https://verify.code402.dev/mcpRun this in your terminal
claude mcp add --transport http code402-verify https://verify.code402.dev/mcpPaste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"code402-verify": {
"url": "https://verify.code402.dev/mcp"
}
}
}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": {
"code402-verify": {
"type": "http",
"url": "https://verify.code402.dev/mcp"
}
}
}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://verify.code402.dev/mcpMenu names can differ slightly by plan and over time.
Your choice stays on this device in a cookie; no account needed.
These 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.
x402_verifyVerify one or more XDR-1 signed receipts offline (free). Returns valid/invalid per receipt with signer recovery, declared signer comparison, and integrity digest. Supply raw_receipt as JSON string or array for batch.
price_lookupLook up pricing for any code402 tool (free). Returns current x402 pricing tiers, accepted networks, and tool availability. Use tool_name for named lookups or url for URL-based lookups.
iban_checkPaid ($0.0029). Validate an IBAN: ISO 13616 structure, country registration, length, MOD 97-10 checksum. Returns pass/fail with all checks and issues. Covers 50 countries.
sanctions_checkPaid ($0.0029). Screen Ethereum addresses and entity names against OFAC/UN/EU sanctions lists. Returns clear/hit with matched entries. Supports both EVM addresses and human-readable names.
onchain_address_checkPaid ($0.0029). Validate an EVM address format and EIP-55 mixed-case checksum. Returns valid/invalid with normalization and checksum status.
lei_checkPaid ($0.0029). Validate a Legal Entity Identifier (LEI, ISO 17442). Checks 20-char alphanumeric format and Mod 97-10 check character. Verified via Rust WASM engine.
luhn_checkPaid ($0.0029). Validate a payment card or account number using the Luhn algorithm (ISO/IEC 7812-1). Checks numeric format and Mod-10 checksum. Verified via Rust WASM engine.
mod97_checkPaid ($0.0029). Calculate ISO 7064 Mod 97-10 remainder for any alphanumeric string. Returns the remainder (0-96, valid=1). Used for IBAN, LEI, and custom identifier validation. Verified via Rust WASM engine.
bundle_verifyPaid ($0.0029–$0.50). Multi-gate compliance bundle: run any combination of IBAN validation, sanctions screening, and EVM address validation in a single call. Returns all gate results + XDR-1 signed receipt. Tier auto-detected from field count.
chain_block_numberPaid ($0.0029). Get the latest Ethereum mainnet block number. Returns block height and timestamp.
chain_balancePaid ($0.0029). Get native ETH balance of any Ethereum address. Returns balance in wei and ETH.
chain_erc20_balancePaid ($0.0029). Get ERC-20 token balance via balanceOf. Returns balance in raw and human-readable form.
chain_noncePaid ($0.0029). Get the next transaction nonce for an Ethereum address.
chain_txPaid ($0.008). Get Ethereum transaction details by hash. Returns from, to, value, gas used, status, block info.
chain_ens_resolvePaid ($0.008). Resolve a .eth ENS name to its Ethereum address via the universal resolver.
chain_gas_pricePaid ($0.0029). Get the current Ethereum mainnet gas price. Returns base fee, priority fee, and max fee in wei and gwei. Useful for estimating transaction costs.
chain_tx_receiptPaid ($0.008). Get the receipt of a confirmed transaction. Returns status (success/fail), gas used, logs, contract address if deployment.
chain_codePaid ($0.0029). Get the deployed bytecode at an address. Returns hex bytecode (empty = EOA, non-empty = contract). Useful for distinguishing contracts from wallets.
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 8, 2026
The publisher (89rat) is not the repo owner (89rat); 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 90 ms (HTTP 200)
No sign-in needed
Read 18 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.
The registry does not list a required key, though some servers ask you to sign in on first use.
It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.
The GitHub repo last changed –, and the latest version (0.2.0) 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, Happo
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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.
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No README found in the repo