Documentation 2025-11-18 18:02 UTC to 2025-11-19 03:21 UTC

21Customize Claude Code's behavior with these command-line flags:21Customize Claude Code's behavior with these command-line flags:

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23| Flag | Description | Example |23| Flag | Description | Example |

24| :------------------------------- | :------------------------------------------------------------------------------------------------------------------------------------------ | :------------------------------------------------------------------------------------------------- |24| :------------------------------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | :------------------------------------------------------------------------------------------------- |

25| `--add-dir` | Add additional working directories for Claude to access (validates each path exists as a directory) | `claude --add-dir ../apps ../lib` |25| `--add-dir` | Add additional working directories for Claude to access (validates each path exists as a directory) | `claude --add-dir ../apps ../lib` |

26| `--agents` | Define custom [subagents](/en/sub-agents) dynamically via JSON (see below for format) | `claude --agents '{"reviewer":{"description":"Reviews code","prompt":"You are a code reviewer"}}'` |26| `--agents` | Define custom [subagents](/en/sub-agents) dynamically via JSON (see below for format) | `claude --agents '{"reviewer":{"description":"Reviews code","prompt":"You are a code reviewer"}}'` |

27| `--allowedTools` | A list of tools that should be allowed without prompting the user for permission, in addition to [settings.json files](/en/settings) | `"Bash(git log:*)" "Bash(git diff:*)" "Read"` |27| `--allowedTools` | A list of tools that should be allowed without prompting the user for permission, in addition to [settings.json files](/en/settings) | `"Bash(git log:*)" "Bash(git diff:*)" "Read"` |

32| `--append-system-prompt` | Append custom text to the end of the default system prompt (works in both interactive and print modes; added in v1.0.55) | `claude --append-system-prompt "Always use TypeScript"` |32| `--append-system-prompt` | Append custom text to the end of the default system prompt (works in both interactive and print modes; added in v1.0.55) | `claude --append-system-prompt "Always use TypeScript"` |

33| `--output-format` | Specify output format for print mode (options: `text`, `json`, `stream-json`) | `claude -p "query" --output-format json` |33| `--output-format` | Specify output format for print mode (options: `text`, `json`, `stream-json`) | `claude -p "query" --output-format json` |

34| `--input-format` | Specify input format for print mode (options: `text`, `stream-json`) | `claude -p --output-format json --input-format stream-json` |34| `--input-format` | Specify input format for print mode (options: `text`, `stream-json`) | `claude -p --output-format json --input-format stream-json` |

35| `--json-schema` | Get validated JSON output matching a JSON Schema after agent completes its workflow (print mode only, see [Agent SDK Structured Outputs](https://docs.claude.com/en/docs/agent-sdk/structured-outputs)) | `claude -p --json-schema '{"type":"object","properties":{...}}' "query"` |

35| `--include-partial-messages` | Include partial streaming events in output (requires `--print` and `--output-format=stream-json`) | `claude -p --output-format stream-json --include-partial-messages "query"` |36| `--include-partial-messages` | Include partial streaming events in output (requires `--print` and `--output-format=stream-json`) | `claude -p --output-format stream-json --include-partial-messages "query"` |

36| `--verbose` | Enable verbose logging, shows full turn-by-turn output (helpful for debugging in both print and interactive modes) | `claude --verbose` |37| `--verbose` | Enable verbose logging, shows full turn-by-turn output (helpful for debugging in both print and interactive modes) | `claude --verbose` |

37| `--max-turns` | Limit the number of agentic turns in non-interactive mode | `claude -p --max-turns 3 "query"` |38| `--max-turns` | Limit the number of agentic turns in non-interactive mode | `claude -p --max-turns 3 "query"` |

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30Failure to forward headers or preserve body fields may result in reduced functionality or inability to use Claude Code features.30Failure to forward headers or preserve body fields may result in reduced functionality or inability to use Claude Code features.

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32<Note>

33 Claude Code determines which features to enable based on the API format. When using the Anthropic Messages format with Bedrock or Vertex, you may need to set environment variable `CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS=1`.

34</Note>

35 

32## Configuration36## Configuration

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34### Model selection38### Model selection

335| `CLAUDE_CODE_CLIENT_CERT` | Path to client certificate file for mTLS authentication |335| `CLAUDE_CODE_CLIENT_CERT` | Path to client certificate file for mTLS authentication |

336| `CLAUDE_CODE_CLIENT_KEY_PASSPHRASE` | Passphrase for encrypted CLAUDE\_CODE\_CLIENT\_KEY (optional) |336| `CLAUDE_CODE_CLIENT_KEY_PASSPHRASE` | Passphrase for encrypted CLAUDE\_CODE\_CLIENT\_KEY (optional) |

337| `CLAUDE_CODE_CLIENT_KEY` | Path to client private key file for mTLS authentication |337| `CLAUDE_CODE_CLIENT_KEY` | Path to client private key file for mTLS authentication |

338| `CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS` | Set to `1` to disable Anthropic API-specific `anthropic-beta` headers. Use this if experiencing issues like "Unexpected value(s) for the `anthropic-beta` header" when using an LLM gateway with third-party providers |

338| `CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC` | Equivalent of setting `DISABLE_AUTOUPDATER`, `DISABLE_BUG_COMMAND`, `DISABLE_ERROR_REPORTING`, and `DISABLE_TELEMETRY` |339| `CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC` | Equivalent of setting `DISABLE_AUTOUPDATER`, `DISABLE_BUG_COMMAND`, `DISABLE_ERROR_REPORTING`, and `DISABLE_TELEMETRY` |

339| `CLAUDE_CODE_DISABLE_TERMINAL_TITLE` | Set to `1` to disable automatic terminal title updates based on conversation context |340| `CLAUDE_CODE_DISABLE_TERMINAL_TITLE` | Set to `1` to disable automatic terminal title updates based on conversation context |

340| `CLAUDE_CODE_IDE_SKIP_AUTO_INSTALL` | Skip auto-installation of IDE extensions |341| `CLAUDE_CODE_IDE_SKIP_AUTO_INSTALL` | Skip auto-installation of IDE extensions |