> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cow.bleu.builders/llms.txt
> Use this file to discover all available pages before exploring further.

# Driver API

> API reference for the Driver service bridging Autopilot and solver engines

# Driver API

The Driver service acts as a bridge between Autopilot and solver engines, handling liquidity aggregation, solution transformation, simulation, and on-chain settlement for CoW Protocol auctions.

## Primary Responsibilities

The Driver manages several critical functions:

* **Liquidity Collection**: Fetches AMM pools, limit orders, and other liquidity sources
* **Auction Translation**: Converts autopilot auction format to solver-compatible format
* **Solution Encoding**: Transforms solver solutions into settlement calldata
* **Simulation**: Validates solutions before on-chain submission
* **Gas Estimation**: Computes accurate gas costs for solutions
* **Settlement Submission**: Broadcasts winning solutions to the blockchain
* **Monitoring**: Tracks transaction status and settlement outcomes

## API Endpoints

### POST /solve

Accepts auction requests from Autopilot and returns computed solutions with scoring details, execution specifications, and gas estimates.

### POST /reveal

Exposes settlement calldata for shadow competition verification, providing both "internalized" (on-chain version) and "uninternalized" (simulation-ready) variants.

### POST /settle

Instructs the Driver to submit winning solutions on-chain, executing encoding, simulation, signing, and broadcast operations.

### GET /quote

Delivers price estimations for individual orders, supporting both legacy and JIT-enabled response formats.

### POST /notify

Receives solver status change notifications from Autopilot.

## Solution Architecture

Solutions contain:

* Identifiers and objective scores
* Submission addresses
* Order execution mappings
* Mapping of token address to uniform clearing price
* Gas cost projections
* Detailed per-order execution information

## Liquidity Sources

The system integrates five primary liquidity categories:

1. **Constant product pools** (Uniswap V2-style)
2. **Weighted product pools** (Balancer)
3. **Stable pools** (Curve)
4. **Concentrated liquidity** (Uniswap V3)
5. **Foreign limit orders** (0x-style)

## Internalization Feature (CIP-2)

Solvers optimize costs by utilizing settlement contract token buffers rather than routing through AMMs. This results in two calldata versions:

* **Internalized**: The on-chain version that uses buffers
* **Uninternalized**: The simulation version with full AMM routing

## Configuration and Best Practices

The Driver operates through TOML-based configuration managing solver engines, liquidity sources, and settlement parameters.

For production reliability:

* Ensure accurate gas estimation
* Comply with deadlines
* Perform thorough pre-submission simulation
* Maintain detailed error logging
* Monitor performance metrics continuously