Classification

A transparent heuristic. Not a hidden model.

Every request is classified before it is routed. The same rules live in Python and in the TypeScript SDK.

Output

{
  "p_small_quality": 0.43,
  "recommended_tier": "frontier",
  "complexity": 5,
  "category": "system_design"
}

P(quality | small)

The classifier does not answer easy/hard. It estimates the chance an economy or standard model will clear the quality bar. ≥ 0.90 routes economy, ≥ 0.72 standard, below that frontier. Complexity and category are features that move the probability — not the routing rule.

Signals

Length, code fences, language keywords, math, design language, proofs, races, safety terms, and constraint words. Categories include factual_recall, math, code_generation, code_debug, system_design, reasoning, analysis, and safety_sensitive.

Offline

import { classifyText } from "promptimizer";
classifyText("Design a rate limiter for 1 million QPS");