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

# Cronos

> Everything a program can name on Cronos, and how a program writes each name.

**Preview chain.** Sauce supports transactions on Ethereum, Base, Arc and Solana, and the testnets Arc Testnet, Base Sepolia, Ethereum Sepolia, Solana Devnet and Solana Testnet only. On Cronos a program
compiles (`sauce compile`) and the reads work (`sauce globals`, `sauce price`, `sauce pools`),
and `sauce simulate` runs wherever the release is deployed on the chain, but the `sauce`
command and the MCP server build and send no transaction: `sauce tx`, `sauce run` and
`sauce pot --deploy` are refused,
naming this chain and the supported chains: the last section shows the refusal and how to
request this chain.

| Fact | Value |
| - | - |
| Support | preview: compile and read; no transaction is built or sent |
| Slug (`--chain`) | `cronos`; also `cro` |
| Chain id | 25 |
| Kind | EVM |
| Name in a program | `Cronos` |
| In TypeScript | `import { Cronos } from "@eco-incorp/sauce"`: its tokens and protocol namespaces are properties of it |
| Native coin | CRO (CRO), 18 decimals |
| Sauce | the engine, Kitchen and Routers, at the same addresses on every EVM chain: [Deployments](https://docs.eco.com/sauce-sdk/reference/deployments.md) |

## Tokens

The registry names no token on this chain: a program uses `Token(<address>)`.

## Protocols

The registry records no protocol deployment on this chain.

## Requesting support

On Cronos, `sauce tx`, `sauce run` and `sauce pot --deploy` exit with status 1 before
they reach an endpoint or read a key. The first line `sauce tx` prints is:

```text theme={null}
sauce tx: building the cook transaction is refused: it involves cronos (Cronos, chain id 25), a preview chain. The sauce command and its MCP server build and send transactions only on Ethereum, Base, Arc and Solana, and the testnets Arc Testnet, Base Sepolia, Ethereum Sepolia, Solana Devnet and Solana Testnet. On a preview chain they build and send none. A program still compiles there and globals, price, pools and pot's prediction still read; simulate runs wherever the release is deployed on the chain, and says so where it is not.
```

To request Cronos, contact Eco through [Support and community](https://docs.eco.com/resources/support.md),
naming the chain and its id (Cronos, 25) and what you want to run there.

## Next steps

* [Chains](https://docs.eco.com/sauce-sdk/reference/chains.md): every other chain, with its support.
* [Names and registries](https://docs.eco.com/sauce/names.md): how a name in a program becomes an address on the chain it is compiled for.
* [Glossary](https://docs.eco.com/sauce/glossary.md): the words these pages use, in plain terms.


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