# 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](/guides/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](/guides/api-reference-v-1-overview) to learn more.
:::

## Related pages

- [API Reference](./api-reference-2-index.md)
- [API Reference](./api-reference-index.md)
- [Credal | Documentation](../index.md)
- [Getting Started](./getting-started-index.md)
- [Platform](./platform-index.md)
- [Agent Builder](./platform-agent-builder.md)
- [Copilots](./api-reference-2-copilots.md)
- [What is Credal?](./getting-started-introduction.md)
- [Fetch the status of an agent response](./api-reference-v-1-agents-fetch-response.md)
- [Quickstart](./getting-started-quickstart.md)

# Agent Instructions

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