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

# Agent configuration

> The `coral-agent.toml` file

Agents are created and configured using a `coral-agent.toml` file.  Every agent in Coral (Server, Console, Cloud and
Marketplace) has exactly one `coral-agent.toml` file.

# Syntax

A `coral-agent.toml` file is written in [TOML](https://toml.io/).  This file has a single top-level field, `edition` and
3 tables.

## Edition

The top-level `edition` field is a number indicating the edition of the `coral-agent.toml` file, allowing the Coral
server and other applications to quickly identify whether or not they are compatible.

**The current edition is 4**

## Tables

### [agent table](/reference/agent/tables/agent)

Contains basic information about the agent, such as its name and version.  This table is required, and many of its
fields are required.

### [runtimes table](/reference/agent/tables/runtimes)

An agent  **must define 1 or more** of the following:

| Runtime                                                     | Environment             | Description                                                                       |
| ----------------------------------------------------------- | ----------------------- | --------------------------------------------------------------------------------- |
| [runtimes.executable](/reference/agent/runtimes/executable) | development             | Used exclusively for development.  Cannot be used in the marketplace.             |
| [runtimes.docker](/reference/agent/runtimes/docker)         | production              | Production runtime custom agents, highly configurable                             |
| [runtimes.prototype](/reference/agent/runtimes/prototype)   | production, development | Limited configuration, but can be used for rapid agent prototyping and production |

### [options table](/reference/agent/tables/options)

The `options` table contains up to 512 unique options that allow your agent to be configured at runtime, by applications.

Options are optional; however, almost every agent will have options.  Options are for example used for:

* API keys used by LLMs
* API keys or tokens used by MCP servers
* Prompting adjustments

### [llm table](/reference/agent/tables/llm)

A table that describes the LLM requirements of the agent.  This table is optional; however, agents that do not use
LLM proxies will be limited in what Coral features they support.