Evaluation

Trace Grading

Scoring AI workflow traces — not just final outputs — to detect quality issues at the step level: bad retrievals, wrong tool calls, low-confidence reasoning.

Operating principle

Production AI is not a prompt. It is a system of context, tools, permissions, traces, evals, and feedback loops.

What it is

Trace grading is evaluation at the step level instead of the output level. Where a basic eval scores 'did the final answer match the gold response,' trace grading scores 'did each step of the reasoning hold up' — did retrieval bring back the right chunks, did the tool calls have the right arguments, did the model's intermediate reasoning make sense, did it stop when it should have.

Why it matters

Output-only evaluation hides the workflow's actual behavior. An agent can get the right answer for the wrong reasons (lucky retrieval, accidental tool match) and fail catastrophically on the next case that doesn't have the same luck. Trace grading is how the team understands what the workflow is actually doing, not just what it produces.

How it works

Production traces are sampled and scored at the step level using rubrics or LLM-as-judge with calibration. Low-scoring steps are surfaced as candidate regressions even when the final output passed. The same traces feed the regression set when failure clusters become repeatable.

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