core.events

Event models

Core LLM/tool event types:

• PromptEvent: emitted when a prompt is sent to a provider
• LLMEvent: emitted when a provider response is received
• ToolEvent: emitted when a tool runs (result or error)

All of these events extend BaseEvent from coevolved.base.tracing.

Emission points

Events are emitted from:

• llm_step(...): emits PromptEvent (rendered prompt metadata) and LLMEvent (response metadata)
• tool_step(...): emits ToolEvent (args + result/error)

These events are linked back to the originating step invocation via the invocation context (run_id, step_id, invocation_id, group_hash).

Next steps

Tracing concept

How these events fit into the overall tracing system.

core.formatters reference

Built-in formatters for LLM and tool events.