deny array in your permission settings.
To add custom tools, connect an MCP server. To extend Claude with reusable prompt-based workflows, write a skill, which runs through the existing Skill tool rather than adding a new tool entry.
| Tool | Description | Permission Required |
|---|---|---|
Agent | Spawns a subagent with its own context window to handle a task | No |
AskUserQuestion | Asks multiple-choice questions to gather requirements or clarify ambiguity | No |
Bash | Executes shell commands in your environment. See Bash tool behavior | Yes |
CronCreate | Schedules a recurring or one-shot prompt within the current session (gone when Claude exits). See scheduled tasks | No |
CronDelete | Cancels a scheduled task by ID | No |
CronList | Lists all scheduled tasks in the session | No |
Edit | Makes targeted edits to specific files | Yes |
EnterPlanMode | Switches to plan mode to design an approach before coding | No |
EnterWorktree | Creates an isolated git worktree and switches into it | No |
ExitPlanMode | Presents a plan for approval and exits plan mode | Yes |
ExitWorktree | Exits a worktree session and returns to the original directory | No |
Glob | Finds files based on pattern matching | No |
Grep | Searches for patterns in file contents | No |
ListMcpResourcesTool | Lists resources exposed by connected MCP servers | No |
LSP | Code intelligence via language servers: jump to definitions, find references, report type errors and warnings. See LSP tool behavior | No |
NotebookEdit | Modifies Jupyter notebook cells | Yes |
PowerShell | Executes PowerShell commands on Windows. Opt-in preview. See PowerShell tool | Yes |
Read | Reads the contents of files | No |
ReadMcpResourceTool | Reads a specific MCP resource by URI | No |
SendMessage | Sends a message to an agent team teammate, or resumes a subagent by its agent ID. Stopped subagents auto-resume in the background. Only available when CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1 or the --agent-teams flag is set | No |
Skill | Executes a skill within the main conversation | Yes |
TaskCreate | Creates a new task in the task list | No |
TaskGet | Retrieves full details for a specific task | No |
TaskList | Lists all tasks with their current status | No |
TaskOutput | (Deprecated) Retrieves output from a background task. Prefer Read on the task’s output file path | No |
TaskStop | Kills a running background task by ID | No |
TaskUpdate | Updates task status, dependencies, details, or deletes tasks | No |
TeamCreate | Creates an agent team with multiple teammates. Only available when CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1 or the --agent-teams flag is set | No |
TeamDelete | Disbands an agent team and cleans up teammate processes. Only available when CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1 or the --agent-teams flag is set | No |
TodoWrite | Manages the session task checklist. Available in non-interactive mode and the Agent SDK; interactive sessions use TaskCreate, TaskGet, TaskList, and TaskUpdate instead | No |
ToolSearch | Searches for and loads deferred tools when tool search is enabled | No |
WebFetch | Fetches content from a specified URL | Yes |
WebSearch | Performs web searches | Yes |
Write | Creates or overwrites files | Yes |
/permissions or in permission settings. Also see Tool-specific permission rules.
Bash tool behavior
The Bash tool runs each command in a separate process with the following persistence behavior:- Working directory persists across commands. Set
CLAUDE_BASH_MAINTAIN_PROJECT_WORKING_DIR=1to reset to the project directory after each command. - Environment variables do not persist. An
exportin one command will not be available in the next.
CLAUDE_ENV_FILE to a shell script before launching Claude Code, or use a SessionStart hook to populate it dynamically.
LSP tool behavior
The LSP tool gives Claude code intelligence from a running language server. After each file edit, it automatically reports type errors and warnings so Claude can fix issues without a separate build step. Claude can also call it directly to navigate code:- Jump to a symbol’s definition
- Find all references to a symbol
- Get type information at a position
- List symbols in a file or workspace
- Find implementations of an interface
- Trace call hierarchies
PowerShell tool
On Windows, Claude Code can run PowerShell commands natively instead of routing through Git Bash. This is an opt-in preview.Enable the PowerShell tool
SetCLAUDE_CODE_USE_POWERSHELL_TOOL=1 in your environment or in settings.json:
pwsh.exe (PowerShell 7+) with a fallback to powershell.exe (PowerShell 5.1). The Bash tool remains registered alongside the PowerShell tool, so you may need to ask Claude to use PowerShell.
Shell selection in settings, hooks, and skills
Three additional settings control where PowerShell is used:"defaultShell": "powershell"insettings.json: routes interactive!commands through PowerShell. Requires the PowerShell tool to be enabled."shell": "powershell"on individual command hooks: runs that hook in PowerShell. Hooks spawn PowerShell directly, so this works regardless ofCLAUDE_CODE_USE_POWERSHELL_TOOL.shell: powershellin skill frontmatter: runs!`command`blocks in PowerShell. Requires the PowerShell tool to be enabled.
Preview limitations
The PowerShell tool has the following known limitations during the preview:- Auto mode does not work with the PowerShell tool yet
- PowerShell profiles are not loaded
- Sandboxing is not supported
- Only supported on native Windows, not WSL
- Git Bash is still required to start Claude Code
Check which tools are available
Your exact tool set depends on your provider, platform, and settings. To check what’s loaded in a running session, ask Claude directly:/mcp.
See also
- MCP servers: add custom tools by connecting external servers
- Permissions: permission system, rule syntax, and tool-specific patterns
- Subagents: configure tool access for subagents
- Hooks: run custom commands before or after tool execution