Rialto Swap MCP (read-only)

Read-only MCP service for Rialto — the onchain best-execution swap router on Robinhood Chain (chain id 4663) for crypto and tokenized equities, ETFs, and commodities. It deliberately contains no submit, execute, signing, or wallet tool — quoting and pricing only.

Hoodly's own agents get real swap execution through a native, server-wallet tool pair inside the Hoodly API (rialto_read / rialto_action in api-hoodly), not through this MCP. This project exists for any other MCP client — Claude Desktop, an inspector, a third-party agent — that wants Rialto pricing without building the API integration itself.

Tools

• rialto_list_tokens — every token quotable on Rialto for Robinhood Chain (symbol, address, decimals, type). Public, no key needed.

• rialto_get_quote — best-execution quote: expected output, guaranteed minimum, every fee line, route stats, blockers. Requires RIALTO_API_KEY.

• rialto_preflight — validates a quote against baseline safety checks (balance/allowance issues, settlement sanity, staleness, slippage ceiling, fee cap, zero-output guard) before any signing step.

• rialto_build_unsigned_tx — returns the unsigned payload (tx + EIP-712 typed data + signature offset) for a user-signed wallet to complete elsewhere. This server never signs.

Related MCP server: hl-read

Why no execute tool

Rialto's /quote and /gasless/submit responses carry real transactions — rialto_build_unsigned_tx hands back exactly what a wallet needs to sign, and stops there deliberately. Adding a submit/execute tool here would mean either holding a private key in a generically-installable MCP process (a step backwards from any reasonable custody boundary) or forwarding to some external signer this project has no relationship with. Neither is appropriate for a standalone, general-purpose MCP server. If your integration needs to sign, sign in your own client with your own key material, using rialto_build_unsigned_tx's output.

Environment

RIALTO_API_KEY=rialto_live_<prefix>.<secret>   # never logged, never committed
MCP_TRANSPORT=http                              # or stdio
PORT=3008                                       # http mode only
HOST=0.0.0.0                                    # http mode only

Run it

npm install
npm run dev          # stdio: set MCP_TRANSPORT=stdio in .env first

{
  "mcpServers": {
    "rialto": { "command": "node", "args": ["src/index.js"], "env": { "MCP_TRANSPORT": "stdio", "RIALTO_API_KEY": "..." } }
  }
}

Run it with PM2

ecosystem.config.cjs runs the HTTP transport on port 3081. RIALTO_API_KEY still comes from .env (dotenv doesn't override vars PM2 already sets, so PORT/HOST/MCP_TRANSPORT in the config win, and the secret key stays out of the config file).

pm2 start ecosystem.config.cjs   # start
pm2 restart mcp-rialto           # after a code change
pm2 logs mcp-rialto              # tail logs
pm2 stop mcp-rialto              # stop
pm2 delete mcp-rialto            # remove from the pm2 process list
pm2 save                         # persist the process list across reboots

The matching local workflow is SKILL.md.