Code Is More Than Text: Uncertainty Estimation for Code Generation

Three-axis uncertainty estimation framework for code generation outperforms NL-derived baselines

A new arXiv preprint argues that uncertainty estimation (UE) for code generation requires code-specific design rather than methods ported from natural language. The authors propose three orthogonal uncertainty axes—lexical (token entropy), algorithmic (pseudo-code consistency), and functional (behavioral consistency)—grounded in properties unique to code: token fragility, intent-code gap, and executability. Evaluated across five code LLMs, their ensemble improves average AUROC from 0.696 to 0.776 (+8.1 points) over the strongest NL-derived baseline, with a single-pass token entropy method on Qwen3-14B matching multi-pass baselines at 3x lower cost. The work is directly relevant to safe deployment of LLMs in agentic coding pipelines.