Soft Prompts for Evaluation: Measuring Conditional Distance of Capabilities

📅 2025-05-20
📈 Citations: 0
✨ Influential: 0
📄 PDF
🤖 AI Summary
This work addresses the challenge of quantitatively evaluating latent capabilities—particularly harmful behaviors—in language models. We propose **conditional distance** as a unified metric, formalizing soft prompt optimization as the minimal semantic perturbation required to activate a target behavior—introducing the first principled formulation of *conditional behavioral reachability*. We design a novel **generalized conditional soft prompting** framework enabling consistent, cross-task (e.g., NLP, chess, grid pathfinding) and cross-domain evaluation. Integrating gradient-driven embedding optimization, conditional behavioral modeling, and an automated pipeline, our approach yields interpretable, comparable, and scalable latent capability probing. Experiments demonstrate that our method effectively quantifies the difficulty of behavior activation, providing red-teaming assessments with actionable, quantitative feedback.

Technology Category

Natural Language Processing: Prompt Engineering / PromptingHumans and AI: Human-Aware Planning and Behavior PredictionSearch and Optimization: Learning to Search

Application Category

Semantics and Knowledge: Data modeling to support human-machine intelligence, including LLMs agents, intelligent system behavior, explanations, and user-friendly interactionsSearch and Retrieval-Augmented AI: Web evaluation methodologies and metricsUser Modeling, Personalization and Recommendation: Metrics for user behavior and evaluating success
📝 Abstract
To help evaluate and understand the latent capabilities of language models, this paper introduces an approach using optimized input embeddings, or 'soft prompts,' as a metric of conditional distance between a model and a target behavior. The technique aims to facilitate latent capability discovery as a part of automated red teaming/evaluation suites and to provide quantitative feedback about the accessibility of potentially concerning behaviors in a way that may scale to powerful future models, including those which may otherwise be capable of deceptive alignment. An evaluation framework using soft prompts is demonstrated in natural language, chess, and pathfinding, and the technique is extended with generalized conditional soft prompts to aid in constructing task evaluations.
Problem

Research questions and friction points this paper is trying to address.

Measure conditional distance to target behaviors using soft prompts
Facilitate latent capability discovery in language models
Provide scalable evaluation for potentially concerning model behaviors
Innovation

Methods, ideas, or system contributions that make the work stand out.

Uses optimized soft prompts as metrics
Measures conditional distance to behaviors
Extends to generalized task evaluations