ModelRefs / Observable Agent — Agent Pattern
Observable Agent — Agent Pattern
Emit structured traces and metrics for every prompt, tool call, and decision so failures are debuggable.
Overview
Wrap the agent with a tracer that emits run-id-scoped spans for every model call, tool execution, and decision. Pair with an eval harness and run-replay so production failures can be rerun deterministically.
When to use it: You're shipping an agent to production and need to debug failures and run regressions.
Pattern details
| Pattern class | observability |
|---|---|
| Difficulty | intermediate |
| Autonomy | guided |
| Also known as | traced agent, instrumented agent |
| Last reviewed | 2026-06-07 |
Known failure modes
- Missing spans — Some tool calls bypass the tracer. Mitigation: Wrap the tool runtime so every call is automatically spanned.
When not to use it
- Shipping an agent with no traces or evals.
Continue your research
Use these connected ModelRefs sections to compare alternatives, inspect implementation paths, and review the evidence and governance boundaries relevant to Observable Agent — Agent Pattern.
Frequently asked questions
When should I use the Observable Agent agent pattern?
You're shipping an agent to production and need to debug failures and run regressions.
What are common failure modes of Observable Agent?
Missing spans
Is Observable Agent production-ready?
Yes when paired with the safety controls and observability hooks documented on the pattern page.