Tool use & function calling

Giving a model hands — letting it call functions and APIs.

← All concepts

• ADK Tutorial

  Public

  The flagship, end-to-end tutorial for building agents with the Agent Development Kit.

  • Agent fundamentals
  • Tool use & function calling
  • Python
  • ADK
  • Gemini
  Code → ★ 96

• Task Tracker Agent

  Local

  A tiny local agent that manages a task list through tool calls.

  • Agent fundamentals
  • Tool use & function calling
  • Python
  • uv
  Local · write-up coming

• Trip Planner Agent

  Local

  A local multi-step planner that decomposes a trip into tool-driven subtasks.

  • Workflows & orchestration
  • Tool use & function calling
  • Python
  • uv
  Local · write-up coming

• Discovery Agent

  Public

  Dynamic tool discovery via Google Cloud Agent Registry and ADK.

  • A2A & agent registry
  • Tool use & function calling
  • Python
  • ADK
  • Agent Registry
  Code →

• Agent + MCP v2

  Public

  An agent wired up to tools and data through the Model Context Protocol.

  • MCP (Model Context Protocol)
  • Tool use & function calling
  • Python
  • MCP
  Code →

• ADK Builder (Gemini CLI ext)

  Public

  A Gemini CLI extension for vibe-coding ADK agents through natural language.

  • Agent skills
  • Tool use & function calling
  • Python
  • Gemini CLI
  Code →