cow-mcp

April 26, 2026 · View on GitHub

MCP (Model Context Protocol) server exposing CoW Protocol to AI agents. Lets an agent fetch quotes, build and submit orders, cancel them, and browse a wallet's trade history.

The server never holds private keys. It returns EIP-712 typed-data payloads for the host wallet to sign; the agent submits the signed result back through cow_submit_order / cow_submit_cancellation.

Install

Hosted (HTTP)

Public deployment: https://cow-mcp.netlify.app/mcp. Works with any MCP client that speaks Streamable HTTP — claude.ai web, Claude Desktop, Claude Code, Cursor, ChatGPT, and others.

claude mcp add cow-mcp -s project --transport http https://cow-mcp.netlify.app/mcp

.mcp.json:

{
  "mcpServers": {
    "cow-mcp": {
      "type": "http",
      "url": "https://cow-mcp.netlify.app/mcp"
    }
  }
}

Local (stdio via `npx`)

Requires Node 20+.

claude mcp add cow-mcp -s project -- npx -y cow-mcp

.mcp.json:

{
  "mcpServers": {
    "cow-mcp": {
      "command": "npx",
      "args": ["-y", "cow-mcp"]
    }
  }
}

Other clients: refer to their docs for the exact config field name.

Environment variables (local mode only)

Variable	Purpose
`COW_RPC_URL_<CHAIN_ID>`	Pin a per-chain RPC for `cow_check_approval`. Defaults to the chain's `*.publicnode.com` then viem's bundled RPC. Example: `COW_RPC_URL_8453=https://mainnet.base.org`

Try it

Use case	Prompt
Quote a swap	"Quote 1 WETH for USDC on Arbitrum."
Inspect an order	"What's the status of order `0xabc…`?"
Wallet trade history	"Show me vitalik.eth's last 10 CoW trades on mainnet."
Find a token	"Is there a COW token on Gnosis? Give me the address."
Place a swap	"Sell 0.1 WETH for USDC on Sepolia from `0x…`. Default slippage."
Cancel an open order	"Cancel order `0xabc…`."
Check approval	"Have I approved USDC for CoW on Base, owner `0x…`?"

For the full natural-language → swap recipe (intent parsing, confirmation, approval, build, sign, submit, poll), load skills/cow-swap/SKILL.md into your host.

Tools

Read

Tool	Purpose
`cow_get_quote`	Indicative price + fee for a swap
`cow_get_order`	Look up an order by uid (status, executed amounts, tx)
`cow_get_trades`	Recent trades for a wallet (paginated: `limit` ≤ 100, `offset` for older pages)
`cow_list_chains`	All chains CoW supports (id, name, native symbol)
`cow_list_tokens`	Supported tokens for a chain, optional symbol/name search

Write (signed externally)

Tool	Purpose
`cow_build_order`	Turn quote + slippage into an EIP-712 payload to sign
`cow_submit_order`	POST a signed order to the orderbook → returns `uid`
`cow_build_cancellation`	EIP-712 payload to cancel an open order off-chain
`cow_submit_cancellation`	POST the signed cancellation
`cow_check_approval`	Read on-chain `allowance(owner, vaultRelayer)` for a sell token
`cow_build_approval`	Encode `approve()` calldata for the GPv2 vault relayer (host sends it)

sellToken / buyToken accept either a 0x address or a token symbol (e.g. "WETH"). Symbols resolve against per-chain CoW token lists; unknown or ambiguous symbols return a hint to call cow_list_tokens.

Every tool takes a chainId (defaults to 1). Use cow_list_chains to enumerate at runtime.

Swap flow

agent → cow_get_quote                    → { sellAmount, buyAmount, quoteId }
agent → cow_check_approval               → { approved, allowance, spender }
  (if not approved)
  agent → cow_build_approval             → { to, data, value }
  host wallet broadcasts the approve tx on-chain
agent → cow_build_order(from, slippage)  → { typedData, orderDigest, appData }
host wallet signs typedData (EIP-712, externally to the MCP server)
agent → cow_submit_order(order, signature, appData) → { uid }
agent → cow_get_order(uid)               → polled until fulfilled

Cancel works the same way: cow_build_cancellation(uid) → host signs → cow_submit_cancellation.

appData round-trip: cow_build_order returns appData as an inline JSON string. Pass that exact string back to cow_submit_order — re-serializing it (even with the same keys) changes the keccak-256 hash and the orderbook will reject the signature.

Wallet boundary

cow-mcp does not sign and does not broadcast. Signing typedData and submitting approval calldata is the host wallet's job — keeping cow-mcp compatible with any wallet integration (local keystore, EIP-1193, Safe / 4337 with signingScheme: "eip1271", embedded MPC).

cow_submit_order and cow_submit_cancellation require user confirmation via MCP elicitation; hosts without elicitation support fall through to the skill-level gate.

Known limitations

Single-chain orderbook only. Both legs of an order must be on the same chain. Cross-chain (CoW's @cowprotocol/sdk-bridging) isn't exposed yet.
No trade timestamps. The orderbook /trades endpoint returns only blockNumber / logIndex. Call cow_get_order(uid) per trade if you need creationDate.

Development

pnpm install
pnpm dev          # run via tsx (stdio)
pnpm test         # vitest
pnpm check        # typecheck + prettier + eslint + tests
pnpm fix          # prettier --write + eslint --fix
pnpm build        # compile to dist/

To point an MCP client at a local checkout, swap npx -y cow-mcp for node /absolute/path/to/cow-mcp/dist/index.js.

A Dev Container config (.devcontainer/) is available for isolated development inside Docker — useful as a guard against npm supply-chain attacks. See .devcontainer/README.md.

License

MIT