Is Grep All You Need? How Agent Harnesses Reshape Agentic Search
- Prior work often evaluates retrieval strategies for LLM agents in isolation rather than within a full iterative agent workflow.
- The interaction between retrieval strategies, agent structure, custom versus provider-native CLI, and tool-calling paradigms, inline versus file-based result passing, has remained largely unexplored.
- Understanding how retrieval strategies behave as corpus noise increases has been limited, even though this is an important aspect of real-world agent deployments.
- We conducted a multifaceted empirical study comparing lexical retrieval, grep, and semantic retrieval, vector search, across different agent harnesses and tool-calling structures.
- The evaluation used a subset of 116 questions from the LongMemEval benchmark and focused on multi-session conversations with varying levels of irrelevant distractor content.
- We evaluated five different LLMs and used an auxiliary LLM judge to ensure consistent and objective agent accuracy across all experimental conditions.