# Cast Vote By Signature

Cast a vote on a proposal. The account's voting weight is determined by the number of votes the account had delegated at the time that proposal state became active. This method has the same purpose as Cast Vote but it instead enables offline signatures to participate in Agile governance voting. For more details on how to create an offline signature, review [EIP-712](https://eips.ethereum.org/EIPS/eip-712).

**Governor Alpha**

```
function castVoteBySig(uint proposalId, bool support, uint8 v, bytes32 r, bytes32 s)
```

* `proposalId`: ID of a proposal in which to cast a vote.
* `support`: A boolean of true for 'yes' or false for 'no' on the proposal vote.
* `v`: The recovery byte of the signature.
* `r`: Half of the ECDSA signature pair.
* `s`: Half of the ECDSA signature pair.
* `RETURN`: No return, reverts on error.

**Solidity**

```
GovernorAlpha gov = GovernorAlpha(0x123...); // contract address
gov.castVoteBySig(proposalId, true, v, r, s);
```

**Web3 1.2.6**

```javascript
const tx = await gov.methods.castVoteBySig(proposalId, false, v, r, s).send({});
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.agilefi.org/governance/cast-vote-by-signature.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.