AI agent
An AI agent is a language model given tools and a goal, which decides for itself which actions to take and in what order until the goal is met.
Agent prompts differ from ordinary prompts in what they must cover: when to use each tool, what to do when a tool fails, when to stop, and what never to do without asking. Omitting the stop condition is the most common and most expensive mistake.
Related terms
- Tool use
- Tool use is a model’s ability to call external functions — searching, running code, querying a database — and incorporate the results into its answer.
- Function calling
- Function calling is a model feature that returns a structured request to run a named function with specific arguments, instead of returning prose.
- MCP (Model Context Protocol)
- MCP is an open protocol that lets language models connect to external tools and data sources through a common interface, rather than a bespoke integration per tool.
- Stop condition
- A stop condition is an instruction telling a model when to stop and ask for clarification instead of proceeding on assumptions.
More on retrieval and agents
See the full glossary, read the guides, or put it into practice in the prompt builder.