# Trace-to-fix: what evidence makes an agent behavior change reviewable?

**URL:** <https://forum.langchain.com/t/trace-to-fix-what-evidence-makes-an-agent-behavior-change-reviewable/4858>\
**Category:** Talking Shop\
**Created:** [October 27, 2026, 3:20pm UTC](https://forum.langchain.com/t/trace-to-fix-what-evidence-makes-an-agent-behavior-change-reviewable/4858 "2026-10-27T15:20:33Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![vittorfp](https://yyz1.discourse-cdn.com/flex007/user_avatar/forum.langchain.com/vittorfp/32/3663_2.png) [@vittorfp](https://forum.langchain.com/u/vittorfp)\
**Post date:** [October 27, 2026, 3:20pm UTC](https://forum.langchain.com/t/trace-to-fix-what-evidence-makes-an-agent-behavior-change-reviewable/4858/1 "2026-10-27T15:20:33Z")

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I am looking for practical feedback from people using LangSmith-style traces, evals, and incident review workflows.

I am testing a small open-source artifact called `change_proposal`: a plain JSON file that sits after observability/evals and records:

- what behavior was observed;
- what outcome/eval signal made it important;
- what change is proposed;
- what evidence supports it;
- how to validate it;
- how to roll it back.

Repo: [GitHub - vittorfp/agent-change-proposals: Evidence-backed improvement proposals for AI agents. · GitHub](https://github.com/vittorfp/agent-change-proposals)  
Example: [agent-change-proposals/examples/declared-intent/change\_proposal.example.json at main · vittorfp/agent-change-proposals · GitHub](https://github.com/vittorfp/agent-change-proposals/blob/main/examples/declared-intent/change_proposal.example.json)  
Discussion: [Should evidence-backed agent change proposals exist? · vittorfp/agent-change-proposals · Discussion #6 · GitHub](https://github.com/vittorfp/agent-change-proposals/discussions/6)

This is not meant to replace LangSmith, tracing, or eval runners. I am trying to understand the handoff after traces/evals reveal a problem: how does that become a reviewable prompt/tool/retrieval/guardrail change?

The feedback I would value most:

1. Would this artifact fit PR review, eval review, CI, incident follow-up, or none of those?
2. What trace/eval evidence would make a proposed behavior change trustworthy enough to review?
3. For CI gating, should fields like immutable evidence refs, baseline/candidate artifact IDs, evaluator and dataset versions, metric threshold, sample count, and rollback trigger live under `validation`, typed `evidence`, or a separate gate/decision object?
4. Is this useful glue around observability/evals, or just extra ceremony around something teams already solve another way?

Blunt feedback is welcome. I am trying to decide what should stay plain JSON, what should become stricter, and what would make the artifact actually fit real agent improvement workflows.