4.3 Built-in Tool Inventory
Claude Code includes 60+ built-in tools, organized into 6 categories by functional domain. These categories reflect the core capability model of a coding agent: File Operations are the foundation (read, write, and search are the highest-frequency operations), Agent Management & Team Collaboration supports multi-Agent execution, User Interaction and System ensure human-in-the-loop control, and Tool Extensions unify skills, deferred tool loading, and MCP/LSP external capabilities. The guiding principle for tool selection is "cover 95% of a developer's daily workflow"—the remaining 5% is handled by BashTool (the universal fallback), skills, and MCP extensions.
| Category | Tool | Description |
|---|---|---|
| File Operations | BashTool | Shell command execution (the most complex tool) |
| FileReadTool | Read file contents (supports images, PDF, Jupyter) | |
| FileEditTool | Precise string replacement editing (core editing tool) | |
| FileWriteTool | Create/overwrite files | |
| GlobTool | Pattern-based file matching | |
| GrepTool | Regex file content search (based on ripgrep) | |
| NotebookEditTool | Jupyter Notebook editing | |
| Network | WebFetchTool | Fetch web page content |
| WebSearchTool | API-driven web search | |
| Agent Management & Team Collaboration | AgentTool | Spawn sub-Agents (core of multi-Agent architecture) |
| TaskOutputTool | Output task results | |
| TaskStopTool | Stop background tasks | |
| TaskCreate/Get/Update/ListTool | Task management v2 (see Chapter 11) | |
| SendMessageTool | Inter-Agent communication | |
| TeamCreateTool | Create Agent teams | |
| TeamDeleteTool | Delete Agent teams | |
| ListPeersTool | List peer Agents | |
| User Interaction | AskUserQuestionTool | Ask users questions |
| TodoWriteTool | Manage to-do lists | |
BriefTool (model-facing name SendUserMessage) | Send a message to the user (the user-visible reply channel in assistant/background mode; supports markdown and attachments) | |
| System | EnterPlanModeTool | Enter planning mode |
| ExitPlanModeTool | Exit planning mode | |
| EnterWorktreeTool | Enter Git Worktree isolation | |
| ExitWorktreeTool | Exit Worktree | |
| ConfigTool | Configuration management | |
| Tool Extensions | SkillTool | Load and execute skills |
| ToolSearchTool | Search and load deferred tools | |
| ListMcpResourcesTool | List MCP resources | |
| ReadMcpResourceTool | Read MCP resources | |
| MCPTool | MCP tool proxy | |
| LSPTool | Language server operations |