Dynamic System Instructions and Tool Exposure for Efficient Agentic LLMs
On the map: LLM agents and tool use → Tool learning and function calling
Abstract (arXiv)
Large Language Model (LLM) agents often run for many steps while re-ingesting long system instructions and large tool catalogs each turn. This increases cost, agent derailment probability, latency, and tool-selection errors. We propose Instruction-Tool Retrieval (ITR), a RAG variant that retrieves, per step, only the minimal system-prompt fragments and the smallest necessary subset of tools. ITR composes a dynamic runtime system prompt and exposes a narrowed toolset with confidence-gated fallbacks. Using a controlled benchmark with internally consistent numbers, ITR reduces per-step context tokens by 95%, improves correct tool routing by 32% relative, and cuts end-to-end episode cost by 70% versus a monolithic baseline. These savings enable agents to run 2-20x more loops within context limits. Savings compound with the number of agent steps, making ITR particularly valuable for long-running autonomous agents. We detail the method, evaluation protocol, ablations, and operational guidance for practical deployment.
Key facts. Cited by 3 papers in the map (data through 14 Oct 2026). Placed in Tool learning and function calling, one of 16 directions in LLM agents and tool use. Builds on 26 of its 36 references that are in the map. First posted on arXiv 1 Dec 2025.
Builds on
26 of 36 references.
Closest ancestors · 4
Same direction, newest first
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- 2023Toolformer: Language Models Can Teach Themselves to Use Tools9 Feb
Other references · 22
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- 2023MetaGPT: Meta Programming for A Multi-Agent Collaborative Frameworkcited by 1,808
- 2021WebGPT: Browser-assisted question-answering with human feedbackcited by 1,745
- 2024SWE-agent: Agent-Computer Interfaces Enable Automated Software Engineeringcited by 1,737
- 2020Leveraging Passage Retrieval with Generative Models for Open Domain Question Answeringcited by 1,210
- 2023GAIA: a benchmark for General AI Assistantscited by 1,128
10 more
- 2023Learning to Compress Prompts with Gist Tokenscited by 390
- 2023A Dynamic LLM-Powered Agent Network for Task-Oriented Agent Collaborationcited by 290
- 2023LLMLingua: Compressing Prompts for Accelerated Inference of Large Language Modelscited by 287
- 2023Unleashing the Emergent Cognitive Synergy in Large Language Models: A Task-Solving Agent through Multi-Persona Self-Collaborationcited by 251
- 2024Token-Budget-Aware LLM Reasoningcited by 247
- 2023Agents: An Open-source Framework for Autonomous Language Agentscited by 116
- 2021The Perils of Using Mechanical Turk to Evaluate Open-Ended Text Generationcited by 97
- 2022Prompt Compression and Contrastive Conditioning for Controllability and Toxicity Reduction in Language Modelscited by 97
- 2024Towards Optimizing the Costs of LLM Usagecited by 33
- 2024TRIM: Token Reduction and Inference Modeling for Cost-Effective Language Generationcited by 2
Built on by
Citing papers per year: 2026: 3.
3 papers.
- 2026The Workload-Router-Pool Architecture for LLM Inference Optimization: A Vision Paper from the vLLM Semantic Router Projectcited by 1
- 2026Task-Aware Harness Provisioning for LLM Agents in Mission-Critical Infrastructure Operationscited by 1
- 2026Toollery: Scaling LLM Agents to Thousands of Skills and Toolscited by 0
- 2026Toollery: Scaling LLM Agents to Thousands of Skills and Tools2 Sep 2026
- 2026Task-Aware Harness Provisioning for LLM Agents in Mission-Critical Infrastructure Operations18 Aug 2026
- 2026The Workload-Router-Pool Architecture for LLM Inference Optimization: A Vision Paper from the vLLM Semantic Router Project22 Mar 2026
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