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

# Message Events

| Type                   | Description                                               |
| ---------------------- | --------------------------------------------------------- |
| `agent_started`        | Agent session started                                     |
| `agent_thinking_start` | Agent started thinking (only when streaming is enabled)   |
| `agent_thinking`       | Agent thinking with content                               |
| `agent_response_start` | Agent started responding (only when streaming is enabled) |
| `agent_response`       | Agent response with content                               |
| `agent_tool_use_start` | Tool call started (only when streaming is enabled)        |
| `agent_tool_use`       | Tool call with tool name and input                        |
| `agent_tool_response`  | Tool result with tool name and result                     |
| `agent_cost`           | Agent step cost info                                      |
| `agent_step`           | Step completed with step number                           |
| `agent_completed`      | Agent session finished                                    |
| `agent_error`          | Agent error                                               |