Events & Observability

Overview

AbstractCore emits events for generation, tool execution, retries, sessions, and compaction. Use these hooks to build metrics, dashboards, or guardrails around tool usage without tying yourself to a specific provider.

Global event handlers

Register a process-wide handler with on_global():

from abstractcore import create_llm
from abstractcore.events import EventType, on_global

def on_event(event):
    print(event.type.value, event.source, event.data)

on_global(EventType.GENERATION_COMPLETED, on_event)

llm = create_llm("ollama", model="qwen3:4b")
llm.generate("Say 'ok' and nothing else.")

Common event types

• EventType.GENERATION_STARTED / EventType.GENERATION_COMPLETED
• EventType.TOOL_STARTED / EventType.TOOL_PROGRESS / EventType.TOOL_COMPLETED
• EventType.RETRY_ATTEMPTED / EventType.RETRY_EXHAUSTED
• EventType.VALIDATION_FAILED
• EventType.COMPACTION_STARTED / EventType.COMPACTION_COMPLETED

For the full list, see API Reference (Event System).

Async handlers

If you need async handlers, use GlobalEventBus.on_async(...) (or per-emitter on_async(...)) and emit events with the async emission methods. Most applications only need the sync hooks above.