# AI Agent

> An AI agent is a system in which a language model dynamically directs its own process and tool use in a loop, deciding what actions to take based on environment feedback until a task is complete.

- Identifier: PTL-0063
- Category: Agents & Orchestration
- Canonical URL: https://protologue.com/t/ai-agent/
- Also known as: LLM agent, agentic system, autonomous agent

## Description

Anthropic's widely cited taxonomy distinguishes agents from workflows, in which model calls and tools follow predefined code paths. Agents trade predictability and cost for flexibility on open-ended tasks.

## Related terms

- [ReAct](https://protologue.com/t/react/)
- [Agentic Workflow](https://protologue.com/t/agentic-workflow/)
- [Orchestrator-Workers](https://protologue.com/t/orchestrator-workers/)
- [Agent Memory](https://protologue.com/t/agent-memory/)
- [Context Engineering](https://protologue.com/t/context-engineering/)

## Sources

- Anthropic (2024). Building effective agents. https://www.anthropic.com/research/building-effective-agents

## Cite this entry

Protologue. (2026). AI Agent. In Protologue: A Taxonomy of Prompting and LLM Techniques (v1.0.0, PTL-0063). https://protologue.com/t/ai-agent/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)