Trezor MCP Tools Reference

Detailed parameter reference, example payloads, supported coins, and error codes for the Trezor Suite MCP server.

Server endpoint: POST http://127.0.0.1:21340/mcp Authentication: Authorization: Bearer <token> header required on every request Protocol: JSON-RPC 2.0 (Streamable HTTP transport) MCP version: 2025-03-26

Tool Parameters

trezor_get_address

Get a receive address from the Trezor device.

Automatically selects the correct method (getAddress for UTXO coins, ethereumGetAddress for EVM chains) based on coin type.

trezor_get_public_key

Get the extended public key (xpub) for a derivation path.

trezor_get_account_info

Get account information including balance, transaction history, and UTXOs.

Provide either path or descriptor (at least one recommended).

trezor_send_transaction

Compose, sign, and broadcast a cryptocurrency transaction.

Common parameters:

EVM-specific parameters (eth, pol, bsc, arb, base, op, avax, etc, tsep, thod):

XRP-specific parameters (xrp, txrp):

UTXO coins (btc, ltc, bch, doge, zec): Only coin, to, and value are needed. The tool internally calls composeTransaction which handles UTXO selection, fee estimation, signing, and broadcasting.

Other chains (sol, ada, xlm, trx): Require a full transaction object with chain-specific parameters per TrezorConnect docs.

trezor_push_transaction

Broadcast a signed transaction to the network.

trezor_sign_message

Sign a message with a private key on the Trezor device.

Automatically selects signMessage (Bitcoin) or ethereumSignMessage (EVM) based on coin type.

trezor_verify_message

Verify a signed message.

Automatically selects verifyMessage (Bitcoin) or ethereumVerifyMessage (EVM) based on coin type.

trezor_sign_typed_data

Sign EIP-712 typed structured data using the Trezor device (EVM chains only).

data object structure:

If path is omitted, it is auto-derived for Ethereum (SLIP-44 coin type 60) from the given accountIndex. For EVM-compatible chains that use a different coin type (for example, Ethereum Classic with coin type 61), you must provide an explicit path matching that chain's derivation scheme.

Example JSON-RPC Payloads

Initialize Session

{
    "jsonrpc": "2.0",
    "id": "1",
    "method": "initialize",
    "params": {
        "protocolVersion": "2025-03-26",
        "capabilities": {},
        "clientInfo": { "name": "my-agent", "version": "1.0.0" }
    }
}

Response (note the Mcp-Session-Id header — include it in subsequent requests):

{
    "jsonrpc": "2.0",
    "id": "1",
    "result": {
        "protocolVersion": "2025-03-26",
        "serverInfo": { "name": "trezor-suite-mcp-server", "version": "1.0.0" },
        "capabilities": { "tools": {} }
    }
}

List Tools

{
    "jsonrpc": "2.0",
    "id": "2",
    "method": "tools/list",
    "params": {}
}

Call a Tool

{
    "jsonrpc": "2.0",
    "id": "3",
    "method": "tools/call",
    "params": {
        "name": "trezor_get_account_info",
        "arguments": {
            "coin": "btc",
            "path": "m/84'/0'/0'",
            "details": "basic"
        }
    }
}

Success response:

{
    "jsonrpc": "2.0",
    "id": "3",
    "result": {
        "content": [
            {
                "type": "text",
                "text": "{\"balance\":\"123456\",\"availableBalance\":\"123456\", ...}"
            }
        ]
    }
}

Error response:

{
    "jsonrpc": "2.0",
    "id": "3",
    "result": {
        "content": [
            {
                "type": "text",
                "text": "Error: Unknown coin 'xyz' and no explicit 'path' provided."
            }
        ],
        "isError": true
    }
}

Send Transaction (EVM)

{
    "jsonrpc": "2.0",
    "id": "4",
    "method": "tools/call",
    "params": {
        "name": "trezor_send_transaction",
        "arguments": {
            "coin": "eth",
            "to": "0x742d35Cc6634C0532925a3b844Bc9e7595f2bD18",
            "value": "0.05"
        }
    }
}

Send Transaction (BTC)

{
    "jsonrpc": "2.0",
    "id": "5",
    "method": "tools/call",
    "params": {
        "name": "trezor_send_transaction",
        "arguments": {
            "coin": "btc",
            "to": "bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4",
            "value": "0.001"
        }
    }
}

Sign EIP-712 Typed Data

{
    "jsonrpc": "2.0",
    "id": "6",
    "method": "tools/call",
    "params": {
        "name": "trezor_sign_typed_data",
        "arguments": {
            "data": {
                "types": {
                    "EIP712Domain": [
                        { "name": "name", "type": "string" },
                        { "name": "version", "type": "string" },
                        { "name": "chainId", "type": "uint256" },
                        { "name": "verifyingContract", "type": "address" }
                    ],
                    "Mail": [
                        { "name": "from", "type": "string" },
                        { "name": "to", "type": "string" },
                        { "name": "contents", "type": "string" }
                    ]
                },
                "primaryType": "Mail",
                "domain": {
                    "name": "Example DApp",
                    "version": "1",
                    "chainId": 1,
                    "verifyingContract": "0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC"
                },
                "message": {
                    "from": "Alice",
                    "to": "Bob",
                    "contents": "Hello, Bob!"
                }
            }
        }
    }
}

Supported Coins

Mainnet

Testnet

In paths above, i is the account index (default 0).

Transaction Auto-Fill Details

EVM Chains (eth, pol, bsc, arb, base, op, avax, etc)

Default mode is EIP-1559 (maxFeePerGas + maxPriorityFeePerGas). Switches to legacy mode only if gasPrice is explicitly provided.

XRP

UTXO Coins (btc, ltc, bch, doge, zec)

A single composeTransaction call with push: true handles everything:

• Account discovery and UTXO selection
• Fee estimation
• Transaction signing
• Broadcasting

No individual fields need to be auto-filled — the entire flow is managed internally.

Other Chains (sol, ada, xlm, trx)

No auto-fill is available. You must provide a complete transaction object with all chain-specific parameters as defined in the TrezorConnect documentation for the corresponding sign method (solanaSignTransaction, cardanoSignTransaction, stellarSignTransaction, tronSignTransaction).

Error Codes

JSON-RPC Errors (HTTP-level)

HTTP Status Codes

Tool-Level Errors

Returned as successful JSON-RPC responses with isError: true:

Auto-Broadcast Failure

When signing succeeds but broadcast fails, the response has success: true with both results:

{
    "success": true,
    "payload": {
        "signed": { "...sign result..." },
        "broadcastError": { "...error details..." }
    }
}

Use trezor_push_transaction to retry the broadcast manually with the signed transaction hex.

Session Management

• Session ID is generated on the first initialize call and returned in the Mcp-Session-Id response header
• All subsequent requests must include the Mcp-Session-Id header — requests that omit it or send a mismatched value are rejected with HTTP 404
• If the server returns HTTP 404 "Session not found", send a new initialize request
• Send DELETE /mcp with the session header to terminate a session
• Sessions are in-memory only — they do not survive app restarts