Summary
The rehearsal before something irreversible.
Onchain mistakes do not roll back, and gas estimation alone does not tell you whether a call will revert or touch state you did not expect. One tool covering nine chains means the check is the same wherever you are deploying.
What it is
An MCP server for Crypto APIs' Simulate product, which executes an EVM transaction against current chain state without broadcasting it.
What you get
- The outcome of a transaction previewed before it is signed or sent
- Gas usage and resulting state changes returned from the dry run
- Ethereum, Ethereum Classic, BSC, Polygon, Avalanche C-Chain, Arbitrum, Base, Optimism and Tron through the same call
- Stdio or HTTP transport, the latter on a port you choose
- An n8n path: run it in HTTP mode and point an MCP Client Tool at it
Requirements
Node.js 18+ and a Crypto APIs key, in CRYPTOAPIS_API_KEY or passed on the launch command. Run it with npx @cryptoapis-io/mcp-simulate; HTTP mode listens on a default port you can override.
Setup effort
One command plus a key — npm install @cryptoapis-io/mcp-simulate, then supply credentials