InfiAgent is a general-purpose framework designed to address the instability of Large Language Model (LLM) agents in long-horizon tasks. Traditional agents often fail as task duration increases because they rely on an ever-growing prompt context, which leads to information loss and accumulated errors.

To solve this, InfiAgent introduces a file-centric state abstraction that externalizes the agent’s persistent memory into a structured file system. Instead of maintaining a full history in the prompt, the agent reconstructs its reasoning context at each step using a workspace snapshot and a small, fixed window of recent actions (e.g., the last 10 steps). This approach ensures the reasoning context remains strictly bounded regardless of how long the task lasts.

Key architectural features include:

• Hierarchical Structure: A multi-level system (Alpha, Domain, and Atomic agents) that manages task decomposition and prevents "tool-calling chaos".
• External Attention Pipeline: A mechanism to process massive amounts of information (like reading dozens of papers) outside the main reasoning context, injecting only relevant summaries back into the state.

In evaluations on the DeepResearch benchmark and a complex 80-paper literature review, InfiAgent demonstrated high reliability and coverage. Notably, using a 20B open-source model, it achieved performance competitive with much larger proprietary systems, proving that explicit state externalization is a practical foundation for stable, long-horizon autonomous agents.