What Is a Tool — The API Call Your Agent Makes on Your Behalf
The concept of an AI 'tool' refers to a specific, atomic capability that an AI agent can autonomously invoke. These tools, often defined by a JSON schema for parameters and outputs, are not new in themselves, as APIs have existed for decades. The novelty lies in AI models' ability to reason, select, and chain these tools together to perform complex workflows without human intervention. While the tool layer is considered solved, the focus is shifting towards developing the 'methodology' layer, which governs how agents use these tools effectively. AI
IMPACT Clarifies the fundamental shift in AI agent capabilities from API existence to autonomous API invocation.