# Overview

## Overview

The Credal API v0 provides a simple interface for sending messages to simple
agents using static API keys. Agents called via API v0 cannot access any actions
that require authentication. Sending agent messages via API v0 is considered legacy.

:::callout{intent="note" title="API v1 available in beta"}
API v1 is now available in beta with support for asynchronous agent messaging,
[actions](https://docs.credal.ai/user-guide/platform/governed-actions/overview), and OAuth 2.0
authentication. API v1 is also more performant and can handle higher scale
traffic. [Check out the v1 docs](https://docs.credal.ai/api-reference/v-1/overview) to learn more.
:::

## Related pages

- [API v1 is currently under development](./apis-coming-soon.md)
- [Credal | Documentation](../index.md)
- [Actions](./concepts-actions.md)
- [Getting Started](./getting-started-index.md)
- [Introduction](./getting-started-introduction.md)
- [Agent Builder](./platform-agent-builder.md)
- [Oauth setup](./apis-oauth-setup.md)
- [Agents](./concepts-agents.md)
- [Quickstart](./getting-started-quickstart.md)
- [Service Accounts](./overview-service-accounts.md)

# Agent Instructions

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