Confidence Scoring
Estimating how reliable an agent's output is so the system can decide whether to trust it, retry, or escalate to a human.
Last updated: April 26, 2026
Definition
Confidence scoring assigns a numeric or categorical reliability estimate to each agent output. Common approaches: ask the model to rate its own confidence ("how sure are you, 1-10?"), inspect token-level log probabilities (when the API exposes them), use a separate classifier model to score outputs, or compare against retrieval-grounded sources. The scores then drive routing decisions: high-confidence outputs go straight to the user, medium-confidence go to a self-correction loop, low-confidence escalate to human review. Confidence scoring is what makes human-in-the-loop and human-on-the-loop patterns workable at scale.
A persistent problem: model self-rated confidence is poorly calibrated. A model that says "I am 90% confident" is often wrong much more than 10 percent of the time on out-of-distribution inputs. Two practical fixes. First, calibrate against your own data: log model confidence vs actual correctness, then learn the mapping from raw score to true probability. Second, prefer behavior-based confidence (did the model reach a stable answer across multiple sampled runs? Did retrieval find supporting evidence?) over self-reported confidence. The behavioral signals are more reliable than the asked-for ones.
When To Use
Add confidence scoring as soon as you have variable-stakes decisions where some need human review and some do not. The score is what routes work between automation and humans.
Related Terms
Building with Confidence Scoring?
I've shipped this pattern in real production systems. If you want a second pair of eyes on your architecture, that's what I do.