DLL Execution

What the DLL Execution MCP server does

The DLL Execution MCP server provides two free, read-only capabilities for Base Mainnet transaction workflows. Preflight runs before execution on one unsigned transaction candidate. Verification runs afterward on a transaction that has already been broadcast.

Preflight combines read-only simulation, an estimated L2 execution fee, deterministic policy checks, a structured judgment, and supporting evidence. Its result can indicate PASS, CAUTION, BLOCK, or INDETERMINATE. These states describe the available evidence for the candidate; they do not authorize execution, assess profitability, or provide financial advice.

Verification checks an observed transaction against explicit expectations. A transaction hash is required. The default check is Base inclusion, while receipt success must be requested explicitly with receipt_status: "success". Optional candidate-content checks can also be evaluated.

How it works

Agents send requests through the remote MCP interface using standard client setup. Before execution, the agent supplies an unsigned Base Mainnet transaction candidate to Preflight and receives evidence for deciding what to do next. After broadcasting, it can submit the transaction hash to Verification, whether or not DLL performed the earlier Preflight.

Verification results should be interpreted through verification.state, rather than HTTP status alone. VERIFIED means the requested checks were satisfied, CONTRADICTED means at least one was contradicted, and INDETERMINATE means the available evidence was insufficient.

Tools and capabilities

The DLL Execution MCP server exposes two free read-only tools corresponding to the available execution capabilities:

• Preflight: Evaluates an unsigned Base Mainnet transaction candidate before execution. It returns simulation results, an estimated L2 execution fee, policy checks, judgment, and evidence.
• Verification: Observes an already-broadcast Base Mainnet transaction and checks inclusion, receipt status, and optional candidate content against supplied expectations.

These tools do not require a wallet connection, signature, or payment. The broader HTTP API also documents an execution-cost Benchmark capability, but the MCP section describes two tools: Preflight and Verification.

Limitations and notes

The DLL Execution MCP server supports Base Mainnet only. It does not sign transactions, broadcast them, hold funds, connect wallets, or execute transactions autonomously. It also does not prove ownership of a supplied from address or authorize a transaction.

Simulation reflects observed chain state and cannot guarantee future inclusion, transaction success, or application-level results. The known L2 fee estimate is not the total execution cost; an unavailable fee must be treated as unknown rather than zero. Verification observations do not establish finality, authorization, ownership, causality, or profitability. Even when an L1 fee is observed, total execution cost remains unavailable.

Keep private keys, credentials, and other secrets out of requests. The agent remains responsible for any action taken after receiving the results. Live OpenAPI schemas, metadata, and actual API responses are the canonical contract, while the documentation repository explains the available interfaces and usage boundaries.