Tool decorator
A tool decorator is a programming-language decorator that marks a function as an externally callable tool and can attach metadata or a parameter schema.
Digital Twins in Action
A decorator that marks a Python function as a callable tool for an AI agent.
- How it is used
- Exposes current inverter output to an agent deciding whether excess solar power can support home climate control.
- How deep it goes
- Shows a decorated function and its input-and-return documentation, but does not explain decorator internals.
- Examples
- Uses a local inverter query alongside weather-forecast and home-digital-twin API tools.
- What you can do after
- Apply it via the Strands SDK to make a documented Python function callable by an agent.
Data Analysis with LLMs
The LangChain tool decorator is a Python decorator that converts a function into a tool with metadata describing its name, parameters, and behavior.
- How it is used
- Turns custom Python functions into tools that agents can invoke.
- How deep it goes
- Explains decorator placement, function naming, and type annotations; does not detail decorator internals.
- Examples
- Uses a currency-conversion function to support analysis of video-game sales across currencies.
- What you can do after
- Build it from scratch: decorate a typed Python function for use as an agent tool.
Related concepts
- toolimplements · A tool is an instrument or software capability that enables a person or system to perform a task, obtain information, or interact with resources.
- custom toolimplements · A custom tool is a developer-defined, agent-callable capability that performs domain-specific actions beyond built-in functions and returns results.
- tool usageimplements · Tool use is an AI system's invocation of external software functions, services, or other capabilities to obtain information or perform actions.
- function_tool decoratoralternative to · A decorator or helper that exposes a programming-language function as an agent-callable tool and generates its structured tool description.
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