What are intents in crypto and how do solvers work?

Intents in crypto are a way of trading where you say what you want and let someone else work out how to do it. Instead of sending a transaction that runs a fixed route through a DEX, you sign a message with your limits. Outside parties then compete to fill it.

What are intents in blockchain, and how are they different from transactions?

A normal blockchain transaction is a set of instructions. It names the contract, the function and the inputs, and it runs exactly as written. If prices move, it can fail and you still pay gas.

CoW Protocol's documentation describes an intent as a signed set of trading constraints rather than a transaction that can be executed. It states which token you sell, which you want and the minimum you will accept. A settlement contract checks your signature and those conditions before any trade goes through, so a solver cannot give you less than you signed for.

What are solvers in crypto?

Solvers are the parties that turn intents into actual onchain trades. CoW Protocol describes them as independent participants who post a bond and compete to build the best settlement. Anyone with DeFi knowledge who can write an optimization algorithm can try to become one.

To fill orders, solvers can use onchain liquidity pools, as a DEX aggregator does, and also offchain sources such as private market makers. On CoW Protocol, the solution that gives users the most surplus wins, and the winning solver is rewarded in COW tokens. Other protocols use different names. UniswapX calls them fillers.

How does intent-based trading work on CoW Swap?

CoW Protocol, the system behind the CoW Swap app, collects intents offchain and sells them to solvers in batch auctions. Solvers can bid on single orders or on groups of orders. The protocol throws out group bids that would give any order less than it could get alone, then picks the bids that give users the most in total.

Two features follow from batching:

• Coincidence of wants. If two users want opposite sides of the same pair, they can be matched directly without touching a pool.
• Uniform prices. Orders for the same pair in one batch settle at one price, so reordering them gives no advantage.

CoW says this reduces exposure to MEV such as sandwich attacks. Its docs also say users pay no fee for failed trades and can cover gas in the token they are selling.

How do cross-chain intents work?

Intents also show up in bridging. Blockworks reports that Across and Uniswap Labs developed ERC-7683, a shared format for expressing cross-chain intents so different apps and solvers can read the same orders. An Open Intents Framework, built by contributors from the Ethereum Foundation and others, uses ERC-7683 as its core standard. This is a key building block of chain abstraction.

The trade-off is reliance on solvers. Your limits are enforced by code, but how good a price you get within them depends on how much competition there is.