# Settings Best Practice

![Last Updated](https://img.shields.io/badge/Last_Updated-Apr%2014%2C%202026%2011%3A25%20PM%20PKT-white?style=flat&labelColor=555) ![Version](https://img.shields.io/badge/Claude_Code-v2.1.107-blue?style=flat&labelColor=555)<br>
[![Implemented](https://img.shields.io/badge/Implemented-2ea44f?style=flat)](../.claude/settings.json)

A comprehensive guide to all available configuration options in Claude Code's `settings.json` files. As of v2.1.107, Claude Code exposes **60+ settings** and **170+ environment variables** (use the `"env"` field in `settings.json` to avoid wrapper scripts).

<table width="100%">
<tr>
<td><a href="../">← Back to Claude Code Best Practice</a></td>
<td align="right"><img src="../!/claude-jumping.svg" alt="Claude" width="60" /></td>
</tr>
</table>

## Table of Contents

1. [Settings Hierarchy](#settings-hierarchy)
2. [Core Configuration](#core-configuration)
3. [Permissions](#permissions)
4. [Hooks](#hooks)
5. [MCP Servers](#mcp-servers)
6. [Sandbox](#sandbox)
7. [Plugins](#plugins)
8. [Model Configuration](#model-configuration)
9. [Display & UX](#display--ux)
10. [AWS & Cloud Credentials](#aws--cloud-credentials)
11. [Environment Variables](#environment-variables-via-env)
12. [Useful Commands](#useful-commands)

---

## Settings Hierarchy

Settings apply in order of precedence (highest to lowest):

| Priority | Location | Scope | Shared? | Purpose |
|----------|----------|-------|---------|---------|
| 1 | Managed settings | Organization | Yes (deployed by IT) | Security policies that cannot be overridden |
| 2 | Command line arguments | Session | N/A | Temporary single-session overrides |
| 3 | `.claude/settings.local.json` | Project | No (git-ignored) | Personal project-specific |
| 4 | `.claude/settings.json` | Project | Yes (committed) | Team-shared settings |
| 5 | `~/.claude/settings.json` | User | N/A | Global personal defaults |

**Managed settings** are organization-enforced and cannot be overridden by any other level, including command line arguments. Delivery methods:
- **Server-managed** settings (remote delivery)
- **MDM profiles** — macOS plist at `com.anthropic.claudecode`
- **Registry policies** — Windows `HKLM\SOFTWARE\Policies\ClaudeCode` (admin) and `HKCU\SOFTWARE\Policies\ClaudeCode` (user-level, lowest policy priority)
- **File** — `managed-settings.json` and `managed-mcp.json` (macOS: `/Library/Application Support/ClaudeCode/`, Linux/WSL: `/etc/claude-code/`, Windows: `C:\Program Files\ClaudeCode\`)
- **Drop-in directory** — `managed-settings.d/` alongside `managed-settings.json` for independent policy fragments (v2.1.83). Following the systemd convention, `managed-settings.json` is merged first as the base, then all `*.json` files in the drop-in directory are sorted alphabetically and merged on top. Later files override earlier ones for scalar values; arrays are concatenated and de-duplicated; objects are deep-merged. Hidden files starting with `.` are ignored. Use numeric prefixes to control merge order (e.g., `10-telemetry.json`, `20-security.json`)

Within the managed tier, precedence is: server-managed > MDM/OS-level policies > file-based (`managed-settings.d/*.json` + `managed-settings.json`) > HKCU registry (Windows only). Only one managed source is used; sources do not merge across tiers. Within the file-based tier, drop-in files and the base file are merged together.

> **Note:** As of v2.1.75, the deprecated Windows fallback path `C:\ProgramData\ClaudeCode\managed-settings.json` has been removed. Use `C:\Program Files\ClaudeCode\managed-settings.json` instead.

**Important**:
- `deny` rules have highest safety precedence and cannot be overridden by lower-priority allow/ask rules.
- Managed settings may lock or override local behavior even if local files specify different values.
- Array settings (e.g., `permissions.allow`) are **concatenated and deduplicated** across scopes — entries from all levels are combined, not replaced.

---

## Core Configuration

### General Settings

| Key | Type | Default | Description |
|-----|------|---------|-------------|
| `$schema` | string | - | JSON Schema URL for IDE validation and autocompletion (e.g., `"https://json.schemastore.org/claude-code-settings.json"`) |
| `model` | string | `"default"` | Override default model. Accepts aliases (`sonnet`, `opus`, `haiku`) or full model IDs |
| `agent` | string | - | Set the default agent for the main conversation. Value is the agent name from `.claude/agents/`. Also available via `--agent` CLI flag |
| `language` | string | `"english"` | Claude's preferred response language. Also sets the voice dictation language |
| `cleanupPeriodDays` | number | `30` | Sessions inactive for longer than this period are deleted at startup (minimum 1). Also controls the age cutoff for automatic removal of orphaned subagent worktrees at startup. Setting to `0` is rejected with a validation error. To disable transcript writes in non-interactive mode (`-p`), use `--no-session-persistence` or `persistSession: false` SDK option |
| `autoUpdatesChannel` | string | `"latest"` | Release channel: `"stable"` or `"latest"` |
| `alwaysThinkingEnabled` | boolean | `false` | Enable extended thinking by default for all sessions |
| `skipWebFetchPreflight` | boolean | `false` | Skip WebFetch blocklist check before fetching URLs *(in JSON schema, not on official settings page)* |
| `availableModels` | array | - | Restrict which models users can select via `/model`, `--model`, Config tool, or `ANTHROPIC_MODEL`. Does not affect the Default option. Example: `["sonnet", "haiku"]` |
| `fastModePerSessionOptIn` | boolean | `false` | Require users to opt in to fast mode each session |
| `defaultShell` | string | `"bash"` | Default shell for input-box `!` commands. Accepts `"bash"` (default) or `"powershell"`. Setting `"powershell"` routes interactive `!` commands through PowerShell on Windows. Requires `CLAUDE_CODE_USE_POWERSHELL_TOOL=1` (v2.1.84) |
| `includeGitInstructions` | boolean | `true` | Include built-in commit and PR workflow instructions and the git status snapshot in Claude's system prompt. The `CLAUDE_CODE_DISABLE_GIT_INSTRUCTIONS` environment variable takes precedence over this setting when set |
| `voiceEnabled` | boolean | - | Enable push-to-talk voice dictation. Written automatically when you run `/voice`. Requires a Claude.ai account |
| `showClearContextOnPlanAccept` | boolean | `false` | Show the "clear context" option on the plan accept screen. Set to `true` to restore the option (hidden by default since v2.1.81) |
| `viewMode` | string | - | Default transcript view mode on startup: `"default"`, `"verbose"`, or `"focus"`. Overrides the sticky Ctrl+O selection when set |
| `disableDeepLinkRegistration` | string | - | Set to `"disable"` to prevent Claude Code from registering the `claude-cli://` protocol handler with the operating system on startup. Deep links let external tools open a Claude Code session with a pre-filled prompt via `claude-cli://open?q=...`. The `q` parameter supports multi-line prompts using URL-encoded newlines (`%0A`). Useful in environments where protocol handler registration is restricted or managed separately |
| `showThinkingSummaries` | boolean | `false` | Show extended thinking summaries in interactive sessions. When unset or `false` (default in interactive mode), thinking blocks are redacted by the API and shown as a collapsed stub. Redaction only changes what you see, not what the model generates — to reduce thinking spend, lower the budget or disable thinking instead. Non-interactive mode (`-p`) and SDK callers always receive summaries regardless of this setting |
| `disableSkillShellExecution` | boolean | `false` | Disable inline shell execution for `` !`...` `` and `` ```! `` blocks in skills and custom commands from user, project, plugin, or additional-directory sources. Commands are replaced with `[shell command execution disabled by policy]` instead of being run. Bundled and managed skills are not affected (v2.1.91) |
| `forceRemoteSettingsRefresh` | boolean | `false` | **(Managed only)** Block CLI startup until remote managed settings are freshly fetched. If the fetch fails, the CLI exits (fail-closed). Use in enterprise environments where policy enforcement must be up-to-date before any session begins (v2.1.92) |
| `feedbackSurveyRate` | number | - | Probability (0–1) that the session quality survey appears when eligible. Enterprise admins can control how often the survey is shown. Example: `0.05` = 5% of eligible sessions |

**Example:**
```json
{
  "model": "opus",
  "agent": "code-reviewer",
  "language": "japanese",
  "cleanupPeriodDays": 60,
  "autoUpdatesChannel": "stable",
  "alwaysThinkingEnabled": true
}
```

### Plans & Memory Directories

Store plan and auto-memory files in custom locations.

| Key | Type | Default | Description |
|-----|------|---------|-------------|
| `plansDirectory` | string | `~/.claude/plans` | Directory where `/plan` outputs are stored |
| `autoMemoryDirectory` | string | - | Custom directory for auto-memory storage. Accepts `~/`-expanded paths. Not accepted in project settings (`.claude/settings.json`) to prevent redirecting memory writes to sensitive locations; accepted from policy, local, and user settings |

**Example:**
```json
{
  "plansDirectory": "./my-plans"
}
```

**Use Case:** Useful for organizing planning artifacts separately from Claude's internal files, or for keeping plans in a shared team location.

### Worktree Settings

Configure how `--worktree` creates and manages git worktrees. Useful for reducing disk usage and startup time in large monorepos.

| Key | Type | Default | Description |
|-----|------|---------|-------------|
| `worktree.symlinkDirectories` | array | `[]` | Directories to symlink from the main repository into each worktree to avoid duplicating large directories on disk |
| `worktree.sparsePaths` | array | `[]` | Directories to check out in each worktree via git sparse-checkout (cone mode). Only the listed paths are written to disk |

**Example:**
```json
{
  "worktree": {
    "symlinkDirectories": ["node_modules", ".cache"],
    "sparsePaths": ["packages/my-app", "shared/utils"]
  }
}
```

### Attribution Settings

Customize attribution messages for git commits and pull requests.

| Key | Type | Default | Description |
|-----|------|---------|-------------|
| `attribution.commit` | string | Co-authored-by | Git commit attribution (supports trailers) |
| `attribution.pr` | string | Generated message | Pull request description attribution |
| `includeCoAuthoredBy` | boolean | `true` | **DEPRECATED** - Use `attribution` instead |

**Example:**
```json
{
  "attribution": {
    "commit": "Generated with AI\n\nCo-Authored-By: Claude <noreply@anthropic.com>",
    "pr": "Generated with Claude Code"
  }
}
```

**Note:** Set to empty string (`""`) to hide attribution entirely.

### Authentication Helpers

Scripts for dynamic authentication token generation.

| Key | Type | Description |
|-----|------|-------------|
| `apiKeyHelper` | string | Shell script path that outputs auth token (sent as `X-Api-Key` header) |
| `forceLoginMethod` | string | Restrict login to `"claudeai"` or `"console"` accounts |
| `forceLoginOrgUUID` | string \| array | Require login to belong to a specific organization. Accepts a single UUID string (which also pre-selects that organization during login) or an array of UUIDs where any listed organization is accepted without pre-selection. When set in managed settings, login fails if the authenticated account does not belong to a listed organization; an empty array fails closed and blocks login with a misconfiguration message |

**Example:**
```json
{
  "apiKeyHelper": "/bin/generate_temp_api_key.sh",
  "forceLoginMethod": "console",
  "forceLoginOrgUUID": ["xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx", "yyyyyyyy-yyyy-yyyy-yyyy-yyyyyyyyyyyy"]
}
```

### Company Announcements

Display custom announcements to users at startup (cycled randomly).

| Key | Type | Description |
|-----|------|-------------|
| `companyAnnouncements` | array | Array of strings displayed at startup |

**Example:**
```json
{
  "companyAnnouncements": [
    "Welcome to Acme Corp!",
    "Remember to run tests before committing!",
    "Check the wiki for coding standards"
  ]
}
```

---

## Permissions

Control what tools and operations Claude can perform.

### Permission Structure

```json
{
  "permissions": {
    "allow": [],
    "ask": [],
    "deny": [],
    "additionalDirectories": [],
    "defaultMode": "acceptEdits",
    "disableBypassPermissionsMode": "disable"
  }
}
```

### Permission Keys

| Key | Type | Description |
|-----|------|-------------|
| `permissions.allow` | array | Rules allowing tool use without prompting |
| `permissions.ask` | array | Rules requiring user confirmation |
| `permissions.deny` | array | Rules blocking tool use (highest precedence) |
| `permissions.additionalDirectories` | array | Extra directories Claude can access |
| `permissions.defaultMode` | string | Default permission mode. In Remote environments, only `acceptEdits` and `plan` are honored (v2.1.70+) |
| `permissions.disableBypassPermissionsMode` | string | Prevent bypass mode activation |
| `permissions.skipDangerousModePermissionPrompt` | boolean | Skip the confirmation prompt shown before entering bypass permissions mode via `--dangerously-skip-permissions` or `defaultMode: "bypassPermissions"`. Ignored when set in project settings (`.claude/settings.json`) to prevent untrusted repositories from auto-bypassing the prompt |
| `allowManagedPermissionRulesOnly` | boolean | **(Managed only)** Only managed permission rules apply; user/project `allow`, `ask`, `deny` rules are ignored |
| `allow_remote_sessions` | boolean | **(Managed only)** Allow users to start Remote Control and web sessions. Defaults to `true`. Set to `false` to prevent remote session access *(not in official docs — official permissions page states "Access to Remote Control and web sessions is not controlled by a managed settings key." On Team and Enterprise plans, admins enable/disable via [Claude Code admin settings](https://claude.ai/admin-settings/claude-code))* |
| `autoMode` | object | Customize what the [auto mode](/en/permission-modes#eliminate-prompts-with-auto-mode) classifier blocks and allows. Contains `environment` (trusted infrastructure descriptions), `allow` (exceptions to block rules), and `soft_deny` (block rules) — all arrays of prose strings. **Not read from shared project settings** (`.claude/settings.json`) to prevent repo injection. Available in user, local, and managed settings. Setting `allow` or `soft_deny` **replaces** the entire default list for that section. Run `claude auto-mode defaults` to see built-in rules before customizing |
| `disableAutoMode` | string | Set to `"disable"` to prevent [auto mode](/en/permission-modes#eliminate-prompts-with-auto-mode) from being activated. Removes `auto` from the `Shift+Tab` cycle and rejects `--permission-mode auto` at startup. Can be set at any settings level; most useful in managed settings where users cannot override it |
| `useAutoModeDuringPlan` | boolean | Whether plan mode uses auto mode semantics when auto mode is available. Default: `true`. Not read from shared project settings (`.claude/settings.json`). Appears in `/config` as "Use auto mode during plan" |

### Permission Modes

| Mode | Behavior |
|------|----------|
| `"default"` | Standard permission checking with prompts |
| `"acceptEdits"` | Auto-accept file edits without asking |
| `"askEdits"` | Ask before every operation *(not in official docs — unverified)* |
| `"dontAsk"` | Auto-denies tools unless pre-approved via `/permissions` or `permissions.allow` rules |
| `"viewOnly"` | Read-only mode, no modifications *(not in official docs — unverified)* |
| `"bypassPermissions"` | Skip all permission checks (dangerous) |
| `"auto"` | Background classifier replaces manual prompts (`--enable-auto-mode`). Research preview — requires Team plan + Sonnet/Opus 4.6. Classifier auto-approves read-only and file edits; sends everything else through a safety check. Falls back to prompting after 3 consecutive or 20 total blocks. Configure with `autoMode` setting |
| `"plan"` | Read-only exploration mode |

### Tool Permission Syntax

| Tool | Syntax | Examples |
|------|--------|----------|
| `Bash` | `Bash(command pattern)` | `Bash(npm run *)`, `Bash(* install)`, `Bash(git * main)` |
| `Read` | `Read(path pattern)` | `Read(.env)`, `Read(./secrets/**)` |
| `Edit` | `Edit(path pattern)` | `Edit(src/**)`, `Edit(*.ts)` |
| `Write` | `Write(path pattern)` | `Write(*.md)`, `Write(./docs/**)` |
| `NotebookEdit` | `NotebookEdit(pattern)` | `NotebookEdit(*)` |
| `WebFetch` | `WebFetch(domain:pattern)` | `WebFetch(domain:example.com)` |
| `WebSearch` | `WebSearch` | Global web search |
| `Task` | `Task(agent-name)` | `Task(Explore)`, `Task(my-agent)` |
| `Agent` | `Agent(name)` | `Agent(researcher)`, `Agent(*)` — permission scoped to subagent spawning |
| `Skill` | `Skill(skill-name)` | `Skill(weather-fetcher)` |
| `MCP` | `mcp__server__tool` or `MCP(server:tool)` | `mcp__memory__*`, `MCP(github:*)` |

**Evaluation order:** Rules are evaluated in order: deny rules first, then ask, then allow. The first matching rule wins.

**Read/Edit path patterns:** Permission rules for `Read`, `Edit`, and `Write` support gitignore-style patterns with four prefix types:

| Prefix | Meaning | Example |
|--------|---------|---------|
| `//` | Absolute path from filesystem root | `Read(//Users/alice/file)` |
| `~/` | Relative to home directory | `Read(~/.zshrc)` |
| `/` | Relative to project root | `Edit(/src/**)` |
| `./` or none | Relative path (current directory) | `Read(.env)`, `Read(*.ts)` |

**Bash wildcard notes:**
- `*` can appear at **any position**: prefix (`Bash(* install)`), suffix (`Bash(npm *)`), or middle (`Bash(git * main)`)
- **Word boundary:** `Bash(ls *)` (space before `*`) matches `ls -la` but NOT `lsof`; `Bash(ls*)` (no space) matches both
- `Bash(*)` is treated as equivalent to `Bash` (matches all bash commands)
- Permission rules support output redirections: `Bash(python:*)` matches `python script.py > output.txt`
- The legacy `:*` suffix syntax (e.g., `Bash(npm:*)`) is equivalent to ` *` but is deprecated

**Example:**
```json
{
  "permissions": {
    "allow": [
      "Edit(*)",
      "Write(*)",
      "Bash(npm run *)",
      "Bash(git *)",
      "WebFetch(domain:*)",
      "mcp__*"
    ],
    "ask": [
      "Bash(rm *)",
      "Bash(git push *)"
    ],
    "deny": [
      "Read(.env)",
      "Read(./secrets/**)",
      "Bash(curl *)"
    ],
    "additionalDirectories": ["../shared-libs/"]
  }
}
```

---

## Hooks

Hook configuration (events, properties, matchers, exit codes, environment variables, and HTTP hooks) is maintained in a dedicated repository:

> **[claude-code-hooks](https://github.com/shanraisshan/claude-code-hooks)** — Complete hook reference with sound notification system, all 25 hook events, HTTP hooks, matcher patterns, exit codes, and environment variables.

Hook-related settings keys (`hooks`, `disableAllHooks` (also disables any custom status line), `allowManagedHooksOnly`, `allowedHttpHookUrls`, `httpHookAllowedEnvVars`) are documented there.

For the official hooks reference, see the [Claude Code Hooks Documentation](https://code.claude.com/docs/en/hooks).

---

## MCP Servers

Configure Model Context Protocol servers for extended capabilities.

### MCP Settings

| Key | Type | Scope | Description |
|-----|------|-------|-------------|
| `enableAllProjectMcpServers` | boolean | Any | Auto-approve all `.mcp.json` servers |
| `enabledMcpjsonServers` | array | Any | Allowlist specific server names |
| `disabledMcpjsonServers` | array | Any | Blocklist specific server names |
| `allowedMcpServers` | array | Managed only | Allowlist with name/command/URL matching |
| `deniedMcpServers` | array | Managed only | Blocklist with matching |
| `allowManagedMcpServersOnly` | boolean | Managed only | Only allow MCP servers explicitly listed in managed allowlist |
| `channelsEnabled` | boolean | Managed only | Allow [channels](https://code.claude.com/docs/en/channels) for Team and Enterprise users. When unset or `false`, channel message delivery is blocked regardless of `--channels` flag |
| `allowedChannelPlugins` | array | Managed only | Allowlist of channel plugins that may push messages. Replaces the default Anthropic allowlist when set. Undefined = fall back to the default, empty array = block all channel plugins. Requires `channelsEnabled: true`. Each entry is an object with `marketplace` and `plugin` fields (v2.1.84) |

### MCP Server Matching (Managed Settings)

```json
{
  "allowedMcpServers": [
    { "serverName": "github" },
    { "serverCommand": "npx @modelcontextprotocol/*" },
    { "serverUrl": "https://mcp.company.com/*" }
  ],
  "deniedMcpServers": [
    { "serverName": "dangerous-server" }
  ]
}
```

**Example:**
```json
{
  "enableAllProjectMcpServers": true,
  "enabledMcpjsonServers": ["memory", "github", "filesystem"],
  "disabledMcpjsonServers": ["experimental-server"]
}
```

---

## Sandbox

Configure bash command sandboxing for security.

### Sandbox Settings

| Key | Type | Default | Description |
|-----|------|---------|-------------|
| `sandbox.enabled` | boolean | `false` | Enable bash sandboxing |
| `sandbox.failIfUnavailable` | boolean | `false` | Exit with error when sandbox is enabled but cannot start, instead of running unsandboxed. Useful for enterprise policies that require strict sandboxing (v2.1.83) |
| `sandbox.autoAllowBashIfSandboxed` | boolean | `true` | Auto-approve bash when sandboxed |
| `sandbox.excludedCommands` | array | `[]` | Commands to run outside sandbox |
| `sandbox.allowUnsandboxedCommands` | boolean | `true` | Allow `dangerouslyDisableSandbox`. When set to `false`, the escape hatch is completely disabled and all commands must run sandboxed (or be in `excludedCommands`). Useful for enterprise policies that require strict sandboxing |
| `sandbox.ignoreViolations` | object | `{}` | Map of command patterns to path arrays — suppress violation warnings *(in JSON schema, not on official settings page)* |
| `sandbox.enableWeakerNestedSandbox` | boolean | `false` | Weaker sandbox for Docker (reduces security) |
| `sandbox.network.allowUnixSockets` | array | `[]` | Specific Unix socket paths accessible in sandbox |
| `sandbox.network.allowAllUnixSockets` | boolean | `false` | Allow all Unix sockets (overrides allowUnixSockets) |
| `sandbox.network.allowLocalBinding` | boolean | `false` | Allow binding to localhost ports (macOS) |
| `sandbox.network.allowedDomains` | array | `[]` | Network domain allowlist for sandbox |
| `sandbox.network.deniedDomains` | array | `[]` | Network domain denylist for sandbox *(not in official docs — unverified)* |
| `sandbox.network.httpProxyPort` | number | - | HTTP proxy port 1-65535 (custom proxy) |
| `sandbox.network.socksProxyPort` | number | - | SOCKS5 proxy port 1-65535 (custom proxy) |
| `sandbox.network.allowManagedDomainsOnly` | boolean | `false` | Only allow domains in managed allowlist (managed settings) |
| `sandbox.network.allowMachLookup` | array | `[]` | (macOS only) Additional XPC/Mach service names the sandbox may look up. Supports a single trailing `*` for prefix matching. Needed for tools that communicate via XPC such as the iOS Simulator or Playwright. Example: `["com.apple.coresimulator.*"]` |
| `sandbox.filesystem.allowWrite` | array | `[]` | Additional paths where sandboxed commands can write. Arrays are merged across all settings scopes. Also merged with paths from `Edit(...)` allow permission rules. Prefix: `/` (absolute), `~/` (home), `./` or none (project-relative in project settings, `~/.claude`-relative in user settings). The older `//` prefix for absolute paths still works. **Note:** This differs from [Read/Edit permission rules](#tool-permission-syntax), which use `//` for absolute and `/` for project-relative |
| `sandbox.filesystem.denyWrite` | array | `[]` | Paths where sandboxed commands cannot write. Arrays are merged across all settings scopes. Also merged with paths from `Edit(...)` deny permission rules. Same path prefix conventions as `allowWrite` |
| `sandbox.filesystem.denyRead` | array | `[]` | Paths where sandboxed commands cannot read. Arrays are merged across all settings scopes. Also merged with paths from `Read(...)` deny permission rules. Same path prefix conventions as `allowWrite` |
| `sandbox.filesystem.allowRead` | array | `[]` | Paths to re-allow read access within `denyRead` regions. Takes precedence over `denyRead`. Arrays are merged across all settings scopes. Same path prefix conventions as `allowWrite` |
| `sandbox.filesystem.allowManagedReadPathsOnly` | boolean | `false` | **(Managed only)** Only `allowRead` paths from managed settings are respected. `allowRead` entries from user, project, and local settings are ignored |
| `sandbox.enableWeakerNetworkIsolation` | boolean | `false` | (macOS only) Allow access to system TLS trust (`com.apple.trustd.agent`); reduces security |

**Example:**
```json
{
  "sandbox": {
    "enabled": true,
    "autoAllowBashIfSandboxed": true,
    "excludedCommands": ["git", "docker", "gh"],
    "allowUnsandboxedCommands": false,
    "network": {
      "allowUnixSockets": ["/var/run/docker.sock"],
      "allowLocalBinding": true
    }
  }
}
```

---

## Plugins

Configure Claude Code plugins and marketplaces.

### Plugin Settings

| Key | Type | Scope | Description |
|-----|------|-------|-------------|
| `enabledPlugins` | object | Any | Enable/disable specific plugins |
| `extraKnownMarketplaces` | object | Project | Add custom plugin marketplaces (team sharing via `.claude/settings.json`) |
| `strictKnownMarketplaces` | array | Managed only | Allowlist of permitted marketplaces |
| `skippedMarketplaces` | array | Any | Marketplaces user declined to install *(in JSON schema, not on official settings page)* |
| `skippedPlugins` | array | Any | Plugins user declined to install *(in JSON schema, not on official settings page)* |
| `pluginConfigs` | object | Any | Per-plugin MCP server configs (keyed by `plugin@marketplace`) *(in JSON schema, not on official settings page)* |
| `blockedMarketplaces` | array | Managed only | Block specific plugin marketplaces |
| `pluginTrustMessage` | string | Managed only | Custom message displayed when prompting users to trust plugins |

**Marketplace source types:** `github`, `git`, `directory`, `hostPattern`, `settings`, `url`, `npm`, `file`. Use `source: 'settings'` to declare a small set of plugins inline without setting up a hosted marketplace repository.

**Example:**
```json
{
  "enabledPlugins": {
    "formatter@acme-tools": true,
    "deployer@acme-tools": true,
    "experimental@acme-tools": false
  },
  "extraKnownMarketplaces": {
    "acme-tools": {
      "source": {
        "source": "github",
        "repo": "acme-corp/claude-plugins"
      }
    },
    "inline-tools": {
      "source": {
        "source": "settings",
        "name": "inline-tools",
        "plugins": [
          {
            "name": "code-formatter",
            "source": { "source": "github", "repo": "acme-corp/code-formatter" }
          }
        ]
      }
    }
  }
}
```

---

## Model Configuration

### Model Aliases

| Alias | Description |
|-------|-------------|
| `"default"` | Recommended for your account type |
| `"sonnet"` | Latest Sonnet model (Claude Sonnet 4.6) |
| `"opus"` | Latest Opus model (Claude Opus 4.6) |
| `"haiku"` | Fast Haiku model |
| `"sonnet[1m]"` | Sonnet with 1M token context |
| `"opus[1m]"` | Opus with 1M token context (default on Max, Team, and Enterprise since v2.1.75) |
| `"opusplan"` | Opus for planning, Sonnet for execution |

**Example:**
```json
{
  "model": "opus"
}
```

### Model Overrides

Map Anthropic model IDs to provider-specific model IDs for Bedrock, Vertex, or Foundry deployments.

| Key | Type | Default | Description |
|-----|------|---------|-------------|
| `effortLevel` | string | - | Persist the effort level across sessions. Accepts `"low"`, `"medium"`, or `"high"`. Written automatically when you run `/effort low`, `/effort medium`, or `/effort high`. Supported on Opus 4.6 and Sonnet 4.6 |
| `modelOverrides` | object | - | Map model picker entries to provider-specific IDs (e.g., Bedrock inference profile ARNs). Each key is a model picker entry name, each value is the provider model ID |

**Example:**
```json
{
  "modelOverrides": {
    "claude-opus-4-6": "arn:aws:bedrock:us-east-1:123456789:inference-profile/anthropic.claude-opus-4-6-v1:0",
    "claude-sonnet-4-6": "arn:aws:bedrock:us-east-1:123456789:inference-profile/anthropic.claude-sonnet-4-6-v1:0"
  }
}
```

### Effort Level

The `/model` command exposes an **effort level** control that adjusts how much reasoning the model applies per response. Use the ← → arrow keys in the `/model` UI to cycle through effort levels.

| Effort Level | Description |
|-------------|-------------|
| High (default) | Full reasoning depth, best for complex tasks |
| Medium | Balanced reasoning, good for everyday tasks |
| Low | Minimal reasoning, fastest responses |

**How to use:**
1. Run `/effort low`, `/effort medium`, or `/effort high` to set directly (v2.1.76+)
2. Or run `/model` → select a model → use **← →** arrow keys to adjust
3. The setting persists via the `effortLevel` key in `settings.json`

**Note:** Effort level is available for Opus 4.6 and Sonnet 4.6 on Max and Team plans. The default was changed from High to Medium in v2.1.68, then changed back to **High** for API-key, Bedrock/Vertex/Foundry, Team, and Enterprise users in v2.1.94. As of v2.1.75, 1M context window for Opus 4.6 is available by default on Max, Team, and Enterprise plans.

### Model Environment Variables

Configure via `env` key:

```json
{
  "env": {
    "ANTHROPIC_MODEL": "sonnet",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "custom-haiku-model",
    "ANTHROPIC_DEFAULT_SONNET_MODEL": "custom-sonnet-model",
    "ANTHROPIC_DEFAULT_OPUS_MODEL": "custom-opus-model",
    "CLAUDE_CODE_SUBAGENT_MODEL": "haiku",
    "MAX_THINKING_TOKENS": "10000"
  }
}
```

---

## Display & UX

### Display Settings

| Key | Type | Default | Description |
|-----|------|---------|-------------|
| `statusLine` | object | - | Custom status line configuration |
| `outputStyle` | string | `"default"` | Output style (e.g., `"Explanatory"`) |
| `spinnerTipsEnabled` | boolean | `true` | Show tips while waiting |
| `spinnerVerbs` | object | - | Custom spinner verbs with `mode` ("append" or "replace") and `verbs` array |
| `spinnerTipsOverride` | object | - | Custom spinner tips with `tips` (string array) and optional `excludeDefault` (boolean) |
| `respectGitignore` | boolean | `true` | Respect .gitignore in file picker |
| `prefersReducedMotion` | boolean | `false` | Reduce animations and motion effects in the UI |
| `fileSuggestion` | object | - | Custom file suggestion command (see File Suggestion Configuration below) |

### Global Config Settings (`~/.claude.json`)

These display preferences are stored in `~/.claude.json`, **not** `settings.json`. Adding them to `settings.json` will trigger a schema validation error.

| Key | Type | Default | Description |
|-----|------|---------|-------------|
| `autoConnectIde` | boolean | `false` | Automatically connect to a running IDE when Claude Code starts from an external terminal. Appears in `/config` as **Auto-connect to IDE (external terminal)** when running outside a VS Code or JetBrains terminal |
| `autoInstallIdeExtension` | boolean | `true` | Automatically install the Claude Code IDE extension when running from a VS Code terminal. Appears in `/config` as **Auto-install IDE extension**. Can also be disabled via `CLAUDE_CODE_IDE_SKIP_AUTO_INSTALL` env var |
| `editorMode` | string | `"normal"` | Key binding mode for the input prompt: `"normal"` or `"vim"`. Appears in `/config` as **Editor mode** |
| `showTurnDuration` | boolean | `true` | Show turn duration messages after responses (e.g., "Cooked for 1m 6s"). Edit `~/.claude.json` directly to change |
| `terminalProgressBarEnabled` | boolean | `true` | Show the terminal progress bar in supported terminals (ConEmu, Ghostty 1.2.0+, and iTerm2 3.6.6+). Appears in `/config` as **Terminal progress bar** |
| `teammateMode` | string | `"auto"` | How [agent team](https://code.claude.com/docs/en/agent-teams) teammates display: `"auto"` (picks split panes in tmux or iTerm2, in-process otherwise), `"in-process"`, or `"tmux"`. See [choose a display mode](https://code.claude.com/docs/en/agent-teams#choose-a-display-mode) |

### Status Line Configuration

```json
{
  "statusLine": {
    "type": "command",
    "command": "~/.claude/statusline.sh",
    "padding": 2,
    "refreshInterval": 5
  }
}
```

| Field | Description |
|-------|-------------|
| `type` | Set to `"command"` to run a shell script |
| `command` | Shell command or script path that generates the status line output |
| `padding` | Extra horizontal spacing (in characters) added to status line content. Defaults to `0`. Controls relative indentation beyond the interface's built-in spacing |
| `refreshInterval` | Re-run the command every N seconds in addition to event-driven updates. Minimum is `1`. Useful when the status line shows time-based data (e.g., a clock) or when background subagents change git state while the main session is idle. Leave unset to run only on events (v2.1.97) |

**Status Line Input Fields:**

The status line command receives a JSON object on stdin. For the full JSON schema and examples, see the [Status Line Documentation](https://code.claude.com/docs/en/statusline).

| Field | Description |
|-------|-------------|
| `model.id`, `model.display_name` | Current model identifier and display name |
| `cwd`, `workspace.current_dir` | Current working directory (both contain the same value; `workspace.current_dir` preferred) |
| `workspace.project_dir` | Directory where Claude Code was launched (may differ from `cwd` if working directory changes) |
| `workspace.added_dirs` | Additional directories added via `/add-dir` or `--add-dir` |
| `workspace.git_worktree` | Git worktree name when inside a linked worktree created with `git worktree add`. Absent in the main working tree (v2.1.97) |
| `cost.total_cost_usd` | Total session cost in USD |
| `cost.total_duration_ms` | Total wall-clock time since session started, in milliseconds |
| `cost.total_api_duration_ms` | Total time spent waiting for API responses, in milliseconds |
| `cost.total_lines_added`, `cost.total_lines_removed` | Lines of code changed during the session |
| `context_window.total_input_tokens`, `context_window.total_output_tokens` | Cumulative token counts across the session |
| `context_window.context_window_size` | Maximum context window size in tokens (200000 default, 1000000 for extended context) |
| `context_window.used_percentage` | Pre-calculated percentage of context window used |
| `context_window.remaining_percentage` | Pre-calculated percentage of context window remaining |
| `context_window.current_usage` | Token counts from the last API call (input, output, cache tokens) |
| `exceeds_200k_tokens` | Whether total tokens from the most recent API response exceeds 200k (fixed threshold) |
| `rate_limits.five_hour.used_percentage` | Five-hour rate limit usage percentage (v2.1.80+) |
| `rate_limits.five_hour.resets_at` | Five-hour rate limit reset timestamp (Unix epoch seconds) |
| `rate_limits.seven_day.used_percentage` | Seven-day rate limit usage percentage |
| `rate_limits.seven_day.resets_at` | Seven-day rate limit reset timestamp (Unix epoch seconds) |
| `session_id` | Unique session identifier |
| `session_name` | Custom session name set with `--name` or `/rename`. Absent if no custom name set |
| `transcript_path` | Path to conversation transcript file |
| `version` | Claude Code version |
| `output_style.name` | Name of the current output style |
| `vim.mode` | Current vim mode (`NORMAL` or `INSERT`) when vim mode is enabled |
| `agent.name` | Agent name when running with `--agent` flag or agent settings |
| `worktree.name` | Name of the active worktree (present only during `--worktree` sessions) |
| `worktree.path` | Absolute path to the worktree directory |
| `worktree.branch` | Git branch name for the worktree. Absent for hook-based worktrees |
| `worktree.original_cwd` | Directory before entering the worktree |
| `worktree.original_branch` | Git branch checked out before entering the worktree. Absent for hook-based worktrees |

### File Suggestion Configuration

The file suggestion script receives a JSON object on stdin (e.g., `{"query": "src/comp"}`) and must output up to 15 file paths (one per line).

```json
{
  "fileSuggestion": {
    "type": "command",
    "command": "~/.claude/file-suggestion.sh"
  },
  "respectGitignore": true
}
```

**Example:**
```json
{
  "statusLine": {
    "type": "command",
    "command": "git branch --show-current 2>/dev/null || echo 'no-branch'"
  },
  "spinnerTipsEnabled": true,
  "spinnerVerbs": {
    "mode": "replace",
    "verbs": ["Cooking", "Brewing", "Crafting", "Conjuring"]
  },
  "spinnerTipsOverride": {
    "tips": ["Use /compact at ~50% context", "Start with plan mode for complex tasks"],
    "excludeDefault": true
  }
}
```

---

## AWS & Cloud Credentials

### AWS Settings

| Key | Type | Description |
|-----|------|-------------|
| `awsAuthRefresh` | string | Script to refresh AWS auth (modifies `.aws` dir) |
| `awsCredentialExport` | string | Script outputting JSON with AWS credentials |

**Example:**
```json
{
  "awsAuthRefresh": "aws sso login --profile myprofile",
  "awsCredentialExport": "/bin/generate_aws_grant.sh"
}
```

### OpenTelemetry

| Key | Type | Description |
|-----|------|-------------|
| `otelHeadersHelper` | string | Script to generate dynamic OpenTelemetry headers |

**Example:**
```json
{
  "otelHeadersHelper": "/bin/generate_otel_headers.sh"
}
```

---

## Environment Variables (via `env`)

Set environment variables for all Claude Code sessions.

```json
{
  "env": {
    "ANTHROPIC_API_KEY": "...",
    "NODE_ENV": "development",
    "DEBUG": "true"
  }
}
```

### Common Environment Variables

| Variable | Description |
|----------|-------------|
| `ANTHROPIC_API_KEY` | API key for authentication |
| `ANTHROPIC_AUTH_TOKEN` | OAuth token |
| `CLAUDE_CODE_OAUTH_TOKEN` | OAuth access token for Claude.ai authentication. Alternative to `/login` for SDK and automated environments. Takes precedence over keychain-stored credentials |
| `CLAUDE_CODE_OAUTH_REFRESH_TOKEN` | OAuth refresh token for Claude.ai authentication. When set, `claude auth login` exchanges this token directly instead of opening a browser. Requires `CLAUDE_CODE_OAUTH_SCOPES` |
| `CLAUDE_CODE_OAUTH_SCOPES` | Space-separated OAuth scopes the refresh token was issued with (e.g., `"user:profile user:inference user:sessions:claude_code"`). Required when `CLAUDE_CODE_OAUTH_REFRESH_TOKEN` is set |
| `ANTHROPIC_BASE_URL` | Custom API endpoint |
| `ANTHROPIC_BEDROCK_BASE_URL` | Override Bedrock endpoint URL |
| `ANTHROPIC_BEDROCK_MANTLE_BASE_URL` | Override the Bedrock Mantle endpoint URL. See [Mantle endpoint](https://code.claude.com/docs/en/amazon-bedrock#use-the-mantle-endpoint) |
| `ANTHROPIC_VERTEX_BASE_URL` | Override Vertex AI endpoint URL |
| `ANTHROPIC_BETAS` | Comma-separated Anthropic beta header values |
| `ANTHROPIC_VERTEX_PROJECT_ID` | GCP project ID for Vertex AI |
| `ANTHROPIC_CUSTOM_MODEL_OPTION` | Model ID to add as a custom entry in the `/model` picker. Use to make a non-standard or gateway-specific model selectable without replacing built-in aliases |
| `ANTHROPIC_CUSTOM_MODEL_OPTION_NAME` | Display name for the custom model entry in the `/model` picker. Defaults to the model ID when not set |
| `ANTHROPIC_CUSTOM_MODEL_OPTION_DESCRIPTION` | Display description for the custom model entry in the `/model` picker. Defaults to `Custom model (<model-id>)` when not set |
| `ANTHROPIC_CUSTOM_MODEL_OPTION_SUPPORTED_CAPABILITIES` | Override capability detection for the custom model entry. Comma-separated values (e.g., `effort,thinking`). Required when the custom model supports features the auto-detection cannot confirm. See [model configuration](https://code.claude.com/docs/en/model-config#customize-pinned-model-display-and-capabilities) |
| `ANTHROPIC_MODEL` | Name of the model to use. Accepts aliases (`sonnet`, `opus`, `haiku`) or full model IDs. Overrides the `model` setting |
| `ANTHROPIC_DEFAULT_HAIKU_MODEL` | Override the Haiku model alias with a custom model ID (e.g., for third-party deployments) |
| `ANTHROPIC_DEFAULT_HAIKU_MODEL_NAME` | Customize the Haiku entry label in the `/model` picker when using a pinned model on Bedrock/Vertex/Foundry. Defaults to the model ID |
| `ANTHROPIC_DEFAULT_HAIKU_MODEL_DESCRIPTION` | Customize the Haiku entry description in the `/model` picker. Defaults to `Custom model (<model-id>)` |
| `ANTHROPIC_DEFAULT_HAIKU_MODEL_SUPPORTED_CAPABILITIES` | Override capability detection for a pinned Haiku model. Comma-separated values (e.g., `effort,thinking`). Required when the pinned model supports features the auto-detection cannot confirm |
| `CLAUDECODE` | Set to `1` in shell environments Claude Code spawns (Bash tool, tmux sessions). Not set in hooks or status line commands. Use to detect when a script is running inside a Claude Code shell |
| `CLAUDE_CODE_SKIP_FAST_MODE_NETWORK_ERRORS` | Set to `1` to allow fast mode when the organization status check fails due to a network error. Useful when a corporate proxy blocks the status endpoint |
| `CLAUDE_CODE_USE_BEDROCK` | Use AWS Bedrock (`1` to enable) |
| `CLAUDE_CODE_USE_VERTEX` | Use Google Vertex AI (`1` to enable) |
| `CLAUDE_CODE_USE_FOUNDRY` | Use Microsoft Foundry (`1` to enable) |
| `CLAUDE_CODE_USE_MANTLE` | Use the Bedrock [Mantle endpoint](https://code.claude.com/docs/en/amazon-bedrock#use-the-mantle-endpoint) (`1` to enable) |
| `CLAUDE_CODE_USE_POWERSHELL_TOOL` | Set to `1` to enable the PowerShell tool on Windows (opt-in preview). When enabled, Claude can run PowerShell commands natively instead of routing through Git Bash. Only supported on native Windows, not WSL (v2.1.84) |
| `CLAUDE_REMOTE_CONTROL_SESSION_NAME_PREFIX` | Prefix for auto-generated Remote Control session names. Defaults to the machine hostname |
| `CLAUDE_CODE_ENABLE_TELEMETRY` | Enable/disable telemetry (`0` or `1`) |
| `DISABLE_ERROR_REPORTING` | Disable error reporting (`1` to disable) |
| `DISABLE_AUTOUPDATER` | Set to `1` to disable automatic update checks against the npm registry. Also configurable as a startup-only var — see [CLI Startup Flags](./claude-cli-startup-flags.md#environment-variables) |
| `DISABLE_TELEMETRY` | Disable telemetry (`1` to disable) |
| `MCP_TIMEOUT` | MCP startup timeout in ms |
| `MAX_MCP_OUTPUT_TOKENS` | Max MCP output tokens (default: 25000). Warning displayed when output exceeds 10,000 tokens |
| `API_TIMEOUT_MS` | Timeout in ms for API requests (default: 600000) |
| `BASH_MAX_TIMEOUT_MS` | Bash command timeout |
| `BASH_MAX_OUTPUT_LENGTH` | Max bash output length |
| `CLAUDE_AUTOCOMPACT_PCT_OVERRIDE` | Auto-compact threshold percentage (1-100). Default is ~95%. Set lower (e.g., `50`) to trigger compaction earlier. Values above 95% have no effect. Use `/context` to monitor current usage. Example: `CLAUDE_AUTOCOMPACT_PCT_OVERRIDE=50 claude` |
| `CLAUDE_CODE_MAX_CONTEXT_TOKENS` | Override the context window size Claude Code assumes for the active model. Only takes effect when `DISABLE_COMPACT` is also set. Use when routing to a model through `ANTHROPIC_BASE_URL` whose context window does not match the built-in size for its name |
| `CLAUDE_BASH_MAINTAIN_PROJECT_WORKING_DIR` | Keep cwd between bash calls (`1` to enable) |
| `CLAUDE_CODE_DISABLE_BACKGROUND_TASKS` | Disable background tasks (`1` to disable) |
| `ENABLE_TOOL_SEARCH` | MCP tool search threshold (e.g., `auto:5`) |
| `DISABLE_PROMPT_CACHING` | Disable all prompt caching (`1` to disable) |
| `DISABLE_PROMPT_CACHING_HAIKU` | Disable Haiku prompt caching |
| `DISABLE_PROMPT_CACHING_SONNET` | Disable Sonnet prompt caching |
| `DISABLE_PROMPT_CACHING_OPUS` | Disable Opus prompt caching |
| `ENABLE_PROMPT_CACHING_1H_BEDROCK` | Request 1-hour cache TTL on Bedrock (`1` to enable) |
| `CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS` | Disable experimental beta features (`1` to disable) |
| `CLAUDE_CODE_SHELL` | Override automatic shell detection |
| `CLAUDE_CODE_FILE_READ_MAX_OUTPUT_TOKENS` | Override default file read token limit |
| `CLAUDE_CODE_GLOB_HIDDEN` | Set to `false` to exclude dotfiles from results when Claude invokes the Glob tool. Included by default. Does not affect `@` file autocomplete, `ls`, Grep, or Read |
| `CLAUDE_CODE_GLOB_NO_IGNORE` | Set to `false` to make the Glob tool respect `.gitignore` patterns. By default, Glob returns all matching files including gitignored ones. Does not affect `@` file autocomplete, which has its own `respectGitignore` setting |
| `CLAUDE_CODE_GLOB_TIMEOUT_SECONDS` | Timeout in seconds for Glob file discovery |
| `CLAUDE_CODE_ENABLE_TASKS` | Set to `true` to enable task tracking in non-interactive mode (`-p` flag). Tasks are on by default in interactive mode |
| `CLAUDE_CODE_SIMPLE` | Set to `1` to run with a minimal system prompt and only the Bash, file read, and file edit tools |
| `CLAUDE_CODE_EXIT_AFTER_STOP_DELAY` | Auto-exit SDK mode after idle duration (ms) |
| `CLAUDE_CODE_DISABLE_ADAPTIVE_THINKING` | Disable adaptive thinking (`1` to disable) |
| `CLAUDE_CODE_DISABLE_THINKING` | Force-disable extended thinking (`1` to disable) |
| `DISABLE_INTERLEAVED_THINKING` | Prevent interleaved-thinking beta header from being sent (`1` to disable) |
| `CLAUDE_CODE_DISABLE_1M_CONTEXT` | Disable 1M token context window (`1` to disable) |
| `CLAUDE_CODE_ACCOUNT_UUID` | Override account UUID for authentication |
| `CLAUDE_CODE_DISABLE_GIT_INSTRUCTIONS` | Disable git-related system prompt instructions |
| `CLAUDE_CODE_NEW_INIT` | Set to `true` to make `/init` run an interactive setup flow. Asks which files to generate (CLAUDE.md, skills, hooks) before exploring the codebase. Without this, `/init` generates a CLAUDE.md automatically |
| `CLAUDE_CODE_PLUGIN_SEED_DIR` | Path to one or more read-only plugin seed directories, separated by `:` on Unix or `;` on Windows. Bundle pre-populated plugins into a container image. Claude Code registers marketplaces from these directories at startup and uses pre-cached plugins without re-cloning |
| `ENABLE_CLAUDEAI_MCP_SERVERS` | Enable Claude.ai MCP servers |
| `CLAUDE_CODE_EFFORT_LEVEL` | Set effort level: `low`, `medium`, `high`, `max` (Opus 4.6 only), or `auto` (use model default). Takes precedence over `/effort` and the `effortLevel` setting |
| `CLAUDE_CODE_MAX_TURNS` | Maximum agentic turns before stopping *(not in official docs — unverified)* |
| `CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC` | Equivalent of setting `DISABLE_AUTOUPDATER`, `DISABLE_FEEDBACK_COMMAND`, `DISABLE_ERROR_REPORTING`, and `DISABLE_TELEMETRY` |
| `CLAUDE_CODE_SKIP_SETTINGS_SETUP` | Skip first-run settings setup flow *(not in official docs — unverified)* |
| `CLAUDE_CODE_PROMPT_CACHING_ENABLED` | Override prompt caching behavior *(not in official docs — unverified)* |
| `CLAUDE_CODE_DISABLE_TOOLS` | Comma-separated list of tools to disable *(not in official docs — unverified)* |
| `CLAUDE_CODE_DISABLE_MCP` | Disable all MCP servers (`1` to disable) *(not in official docs — unverified)* |
| `CLAUDE_CODE_MAX_OUTPUT_TOKENS` | Max output tokens per response. Default: 32,000 (64,000 for Opus 4.6 as of v2.1.77). Upper bound: 64,000 (128,000 for Opus 4.6 and Sonnet 4.6 as of v2.1.77) |
| `CLAUDE_CODE_DISABLE_FAST_MODE` | Disable fast mode entirely (`1` to disable) |
| `CLAUDE_CODE_DISABLE_NONSTREAMING_FALLBACK` | Set to `1` to disable the non-streaming fallback when a streaming request fails mid-stream. Streaming errors propagate to the retry layer instead. Useful when a proxy or gateway causes the fallback to produce duplicate tool execution (v2.1.83) |
| `CLAUDE_ENABLE_STREAM_WATCHDOG` | Abort stalled streams (`1` to enable) |
| `CLAUDE_CODE_ENABLE_FINE_GRAINED_TOOL_STREAMING` | Enable fine-grained tool streaming (`1` to enable) |
| `CLAUDE_CODE_DISABLE_AUTO_MEMORY` | Disable auto memory (`1` to disable) |
| `CLAUDE_CODE_DISABLE_FILE_CHECKPOINTING` | Disable file checkpointing for `/rewind` (`1` to disable) |
| `CLAUDE_CODE_DISABLE_ATTACHMENTS` | Disable attachment processing (`1` to disable) |
| `CLAUDE_CODE_DISABLE_CLAUDE_MDS` | Prevent loading CLAUDE.md files (`1` to disable) |
| `CLAUDE_CODE_RESUME_INTERRUPTED_TURN` | Auto-resume if previous session ended mid-turn (`1` to enable) |
| `CLAUDE_CODE_SKIP_PROMPT_HISTORY` | Set to `1` to skip writing prompt history and session transcripts to disk. Sessions started with this variable set do not appear in `--resume`, `--continue`, or up-arrow history. Useful for ephemeral scripted sessions |
| `CLAUDE_CODE_USER_EMAIL` | Provide user email synchronously for authentication |
| `CLAUDE_CODE_ORGANIZATION_UUID` | Provide organization UUID synchronously for authentication |
| `CLAUDE_CONFIG_DIR` | Custom config directory (overrides default `~/.claude`) |
| `CLAUDE_CODE_TMPDIR` | Override the temp directory used for internal temp files. Claude Code appends `/claude/` to this path. Default: `/tmp` on Unix/macOS, `os.tmpdir()` on Windows |
| `ANTHROPIC_CUSTOM_HEADERS` | Custom headers for API requests (`Name: Value` format, newline-separated for multiple headers) |
| `ANTHROPIC_FOUNDRY_API_KEY` | API key for Microsoft Foundry authentication |
| `ANTHROPIC_FOUNDRY_BASE_URL` | Base URL for Foundry resource |
| `ANTHROPIC_FOUNDRY_RESOURCE` | Foundry resource name |
| `AWS_BEARER_TOKEN_BEDROCK` | Bedrock API key for authentication |
| `ANTHROPIC_SMALL_FAST_MODEL` | **DEPRECATED** — Use `ANTHROPIC_DEFAULT_HAIKU_MODEL` instead |
| `ANTHROPIC_SMALL_FAST_MODEL_AWS_REGION` | AWS region for deprecated Haiku-class model override |
| `CLAUDE_CODE_SHELL_PREFIX` | Command prefix prepended to bash commands |
| `BASH_DEFAULT_TIMEOUT_MS` | Default bash command timeout in ms |
| `CLAUDE_CODE_SKIP_BEDROCK_AUTH` | Skip AWS auth for Bedrock (`1` to skip) |
| `CLAUDE_CODE_SKIP_FOUNDRY_AUTH` | Skip Azure auth for Foundry (`1` to skip) |
| `CLAUDE_CODE_SKIP_MANTLE_AUTH` | Skip AWS authentication for Bedrock Mantle (e.g., when using an LLM gateway) |
| `CLAUDE_CODE_SKIP_VERTEX_AUTH` | Skip Google auth for Vertex (`1` to skip) |
| `CLAUDE_CODE_PROXY_RESOLVES_HOSTS` | Allow proxy to perform DNS resolution |
| `CLAUDE_CODE_API_KEY_HELPER_TTL_MS` | Credential refresh interval in ms for `apiKeyHelper` |
| `CLAUDE_CODE_CLIENT_CERT` | Client certificate path for mTLS |
| `CLAUDE_CODE_CLIENT_KEY` | Client private key path for mTLS |
| `CLAUDE_CODE_CLIENT_KEY_PASSPHRASE` | Passphrase for encrypted mTLS key |
| `CLAUDE_CODE_CERT_STORE` | Comma-separated list of CA certificate sources for TLS connections: `bundled` (Mozilla CA set shipped with Claude Code) and/or `system` (OS trust store). Default: `bundled,system`. The native binary distribution is required for system store integration; on the Node.js runtime, only the bundled set is used regardless of this value (v2.1.101) |
| `CLAUDE_CODE_PLUGIN_GIT_TIMEOUT_MS` | Plugin marketplace git clone timeout in ms (default: 120000) |
| `CLAUDE_CODE_PLUGIN_CACHE_DIR` | Override the plugins root directory |
| `CLAUDE_CODE_DISABLE_OFFICIAL_MARKETPLACE_AUTOINSTALL` | Skip auto-adding the official marketplace (`1` to disable) |
| `CLAUDE_CODE_SYNC_PLUGIN_INSTALL` | Wait for plugin install to complete before first query (`1` to enable) |
| `CLAUDE_CODE_SYNC_PLUGIN_INSTALL_TIMEOUT_MS` | Timeout in ms for synchronous plugin install |
| `CLAUDE_CODE_PLUGIN_KEEP_MARKETPLACE_ON_FAILURE` | Set to `1` to keep the existing marketplace cache when a `git pull` fails instead of wiping and re-cloning. Useful in offline or airgapped environments where re-cloning would fail the same way |
| `CLAUDE_CODE_HIDE_ACCOUNT_INFO` | Hide email/org info from UI *(not in official docs — unverified)* |
| `CLAUDE_CODE_DISABLE_CRON` | Disable scheduled/cron tasks (`1` to disable) |
| `DISABLE_INSTALLATION_CHECKS` | Disable installation warnings |
| `DISABLE_FEEDBACK_COMMAND` | Disable the `/feedback` command. The older name `DISABLE_BUG_COMMAND` is also accepted |
| `DISABLE_DOCTOR_COMMAND` | Hide the `/doctor` command (`1` to disable) |
| `DISABLE_LOGIN_COMMAND` | Hide the `/login` command (`1` to disable) |
| `DISABLE_LOGOUT_COMMAND` | Hide the `/logout` command (`1` to disable) |
| `DISABLE_UPGRADE_COMMAND` | Hide the `/upgrade` command (`1` to disable) |
| `DISABLE_EXTRA_USAGE_COMMAND` | Hide the `/extra-usage` command (`1` to disable) |
| `DISABLE_INSTALL_GITHUB_APP_COMMAND` | Hide the `/install-github-app` command (`1` to disable) |
| `DISABLE_NON_ESSENTIAL_MODEL_CALLS` | Disable flavor text and non-essential model calls *(not in official docs — unverified)* |
| `CLAUDE_CODE_DEBUG_LOGS_DIR` | Override debug log file directory path |
| `CLAUDE_CODE_DEBUG_LOG_LEVEL` | Minimum debug log level |
| `CLAUDE_AUTO_BACKGROUND_TASKS` | Force auto-backgrounding of long tasks (`1` to enable) |
| `CLAUDE_CODE_DISABLE_LEGACY_MODEL_REMAP` | Prevent remapping Opus 4.0/4.1 to newer models (`1` to disable) |
| `FALLBACK_FOR_ALL_PRIMARY_MODELS` | Trigger fallback model for all primary models, not just default (`1` to enable) |
| `CCR_FORCE_BUNDLE` | Set to `1` to force `claude --remote` to bundle and upload your local repository even when GitHub access is available. Also configurable as a startup-only var — see [CLI Startup Flags](./claude-cli-startup-flags.md#environment-variables) |
| `CLAUDE_CODE_GIT_BASH_PATH` | Windows only: path to the Git Bash executable (`bash.exe`). Use when Git Bash is installed but not in your PATH |
| `DISABLE_COST_WARNINGS` | Disable cost warning messages |
| `CLAUDE_CODE_SUBAGENT_MODEL` | Override model for subagents (e.g., `haiku`, `sonnet`) |
| `CLAUDE_CODE_SUBPROCESS_ENV_SCRUB` | Set to `1` to strip Anthropic and cloud provider credentials from subprocess environments (Bash tool, hooks, MCP stdio servers). Use for defense-in-depth when subprocesses should not inherit API keys (v2.1.83) |
| `CLAUDE_CODE_SCRIPT_CAPS` | JSON object limiting how many times specific scripts may be invoked per session when `CLAUDE_CODE_SUBPROCESS_ENV_SCRUB` is set. Keys are substrings matched against the command text; values are integer call limits. For example, `{"deploy.sh": 2}` allows `deploy.sh` to be called at most twice. Matching is substring-based; runtime fan-out via `xargs` or `find -exec` is not detected — this is a defense-in-depth control |
| `CLAUDE_CODE_PERFORCE_MODE` | Set to `1` to enable Perforce-aware write protection. When set, Edit, Write, and NotebookEdit fail with a `p4 edit <file>` hint if the target file lacks the owner-write bit, which Perforce clears on synced files until `p4 edit` opens them. Prevents Claude Code from bypassing Perforce change tracking (v2.1.98) |
| `CLAUDE_CODE_MAX_RETRIES` | Override API request retry count (default: 10) |
| `CLAUDE_CODE_MAX_TOOL_USE_CONCURRENCY` | Max parallel read-only tools (default: 10) |
| `CLAUDE_AGENT_SDK_DISABLE_BUILTIN_AGENTS` | Disable built-in subagent types in SDK mode (`1` to disable) |
| `CLAUDE_AGENT_SDK_MCP_NO_PREFIX` | Skip `mcp__<server>__` prefix for MCP tools in SDK mode (`1` to enable) |
| `MCP_CONNECTION_NONBLOCKING` | Set to `true` in `-p` mode to skip the MCP connection wait entirely. Bounds `--mcp-config` server connections at 5s instead of blocking on the slowest server *(in v2.1.89 changelog, not yet on official env-vars page)* |
| `CLAUDE_CODE_SESSIONEND_HOOKS_TIMEOUT_MS` | SessionEnd hook timeout in ms (replaces hard 1.5s limit) |
| `CLAUDE_CODE_DISABLE_FEEDBACK_SURVEY` | Disable feedback survey prompts (`1` to disable) |
| `CLAUDE_CODE_DISABLE_TERMINAL_TITLE` | Disable terminal title updates (`1` to disable) |
| `CLAUDE_CODE_NO_FLICKER` | Set to `1` to enable flicker-free alt-screen rendering. Eliminates visual flicker during fullscreen redraws (v2.1.88) |
| `CLAUDE_CODE_SCROLL_SPEED` | Mouse wheel scroll multiplier for fullscreen rendering. Increase for faster scrolling, decrease for finer control |
| `CLAUDE_CODE_DISABLE_VIRTUAL_SCROLL` | Set to `1` to disable virtual scrolling in fullscreen rendering and render every message in the transcript. Use if scrolling in fullscreen mode shows blank regions where messages should appear |
| `CLAUDE_CODE_DISABLE_MOUSE` | Set to `1` to disable mouse tracking in fullscreen rendering. Useful when mouse events interfere with terminal multiplexers or accessibility tools |
| `CLAUDE_CODE_ACCESSIBILITY` | Set to `1` to keep native terminal cursor visible for screen readers and accessibility tools |
| `CLAUDE_CODE_SYNTAX_HIGHLIGHT` | Set to `0` to disable syntax highlighting in diff output |
| `CLAUDE_CODE_IDE_SKIP_AUTO_INSTALL` | Skip automatic IDE extension installation (`1` to skip) |
| `CLAUDE_CODE_AUTO_CONNECT_IDE` | Override auto IDE connection behavior |
| `CLAUDE_CODE_IDE_HOST_OVERRIDE` | Override IDE host address for connection |
| `CLAUDE_CODE_IDE_SKIP_VALID_CHECK` | Skip IDE lockfile validation (`1` to skip) |
| `CLAUDE_CODE_OTEL_HEADERS_HELPER_DEBOUNCE_MS` | Debounce interval in ms for OTel headers helper script |
| `CLAUDE_CODE_OTEL_FLUSH_TIMEOUT_MS` | Timeout in ms for OpenTelemetry flush |
| `CLAUDE_CODE_OTEL_SHUTDOWN_TIMEOUT_MS` | Timeout in ms for OpenTelemetry shutdown |
| `CLAUDE_ENABLE_BYTE_WATCHDOG` | Set to `1` to force-enable the byte-level streaming idle watchdog, or `0` to force-disable it. When unset, the watchdog is enabled by default for Anthropic API connections. The byte watchdog aborts a connection when no bytes arrive on the wire for the duration set by `CLAUDE_STREAM_IDLE_TIMEOUT_MS` (minimum 5 minutes), independent of the event-level watchdog |
| `CLAUDE_STREAM_IDLE_TIMEOUT_MS` | Timeout in ms for the streaming idle watchdog. Two watchdogs apply: **byte-level** (default and minimum `300000` / 5 minutes, aborts when no bytes arrive on the wire) and **event-level** (default `90000` / 90 seconds, no minimum, aborts when no SSE events arrive). The byte watchdog is enabled by default for Anthropic API connections; control it via `CLAUDE_ENABLE_BYTE_WATCHDOG`. Increase the event timeout if long-running tools or slow networks cause premature timeout errors |
| `OTEL_LOG_TOOL_DETAILS` | Set to `1` to include `tool_parameters` in OpenTelemetry events. Omitted by default for privacy *(in v2.1.85 changelog, not yet on official env-vars page)* |
| `CLAUDE_CODE_MCP_SERVER_NAME` | Name of the MCP server, passed as an environment variable to `headersHelper` scripts so they can generate server-specific authentication headers *(in v2.1.85 changelog, not yet on official env-vars page)* |
| `CLAUDE_CODE_MCP_SERVER_URL` | URL of the MCP server, passed as an environment variable to `headersHelper` scripts alongside `CLAUDE_CODE_MCP_SERVER_NAME` *(in v2.1.85 changelog, not yet on official env-vars page)* |
| `ANTHROPIC_DEFAULT_OPUS_MODEL` | Override Opus model alias (e.g., `claude-opus-4-6[1m]`) |
| `ANTHROPIC_DEFAULT_OPUS_MODEL_NAME` | Customize the Opus entry label in the `/model` picker when using a pinned model on Bedrock/Vertex/Foundry. Defaults to the model ID |
| `ANTHROPIC_DEFAULT_OPUS_MODEL_DESCRIPTION` | Customize the Opus entry description in the `/model` picker. Defaults to `Custom model (<model-id>)` |
| `ANTHROPIC_DEFAULT_OPUS_MODEL_SUPPORTED_CAPABILITIES` | Override capability detection for a pinned Opus model. Comma-separated values (e.g., `effort,thinking`). Required when the pinned model supports features the auto-detection cannot confirm |
| `ANTHROPIC_DEFAULT_SONNET_MODEL` | Override Sonnet model alias (e.g., `claude-sonnet-4-6`) |
| `ANTHROPIC_DEFAULT_SONNET_MODEL_NAME` | Customize the Sonnet entry label in the `/model` picker when using a pinned model on Bedrock/Vertex/Foundry. Defaults to the model ID |
| `ANTHROPIC_DEFAULT_SONNET_MODEL_DESCRIPTION` | Customize the Sonnet entry description in the `/model` picker. Defaults to `Custom model (<model-id>)` |
| `ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES` | Override capability detection for a pinned Sonnet model. Comma-separated values (e.g., `effort,thinking`). Required when the pinned model supports features the auto-detection cannot confirm |
| `MAX_THINKING_TOKENS` | Maximum extended thinking tokens per response |
| `CLAUDE_CODE_AUTO_COMPACT_WINDOW` | Set the context capacity in tokens used for auto-compaction calculations. Defaults to the model's context window (200K standard, 1M for extended context models). Use a lower value (e.g., `500000`) on a 1M model to treat it as 500K for compaction. Capped at actual context window. `CLAUDE_AUTOCOMPACT_PCT_OVERRIDE` is applied as a percentage of this value. Setting this decouples the compaction threshold from the status line's `used_percentage` |
| `DISABLE_AUTO_COMPACT` | Disable automatic context compaction (`1` to disable). Manual `/compact` still works |
| `DISABLE_COMPACT` | Disable all compaction — both automatic and manual (`1` to disable) |
| `CLAUDE_CODE_ENABLE_PROMPT_SUGGESTION` | Enable prompt suggestions |
| `CLAUDE_CODE_PLAN_MODE_REQUIRED` | Require plan mode for sessions |
| `CLAUDE_CODE_TEAM_NAME` | Team name for agent teams |
| `CLAUDE_CODE_TASK_LIST_ID` | Task list ID for task integration |
| `CLAUDE_ENV_FILE` | Custom environment file path |
| `FORCE_AUTOUPDATE_PLUGINS` | Force plugin auto-updates (`1` to enable) |
| `HTTP_PROXY` | HTTP proxy URL for network requests |
| `HTTPS_PROXY` | HTTPS proxy URL for network requests |
| `NO_PROXY` | Comma-separated list of hosts that bypass proxy |
| `MCP_TOOL_TIMEOUT` | MCP tool execution timeout in ms |
| `MCP_CLIENT_SECRET` | MCP OAuth client secret |
| `MCP_OAUTH_CALLBACK_PORT` | MCP OAuth callback port |
| `IS_DEMO` | Enable demo mode |
| `SLASH_COMMAND_TOOL_CHAR_BUDGET` | Character budget for slash command tool output |
| `VERTEX_REGION_CLAUDE_3_5_HAIKU` | Vertex AI region override for Claude 3.5 Haiku |
| `VERTEX_REGION_CLAUDE_3_7_SONNET` | Vertex AI region override for Claude 3.7 Sonnet |
| `VERTEX_REGION_CLAUDE_4_0_OPUS` | Vertex AI region override for Claude 4.0 Opus |
| `VERTEX_REGION_CLAUDE_4_0_SONNET` | Vertex AI region override for Claude 4.0 Sonnet |
| `VERTEX_REGION_CLAUDE_4_1_OPUS` | Vertex AI region override for Claude 4.1 Opus |

---

## Useful Commands

| Command | Description |
|---------|-------------|
| `/model` | Switch models and adjust Opus 4.6 effort level |
| `/effort` | Set effort level directly: `low`, `medium`, `high` (v2.1.76+) |
| `/config` | Interactive configuration UI |
| `/memory` | View/edit all memory files |
| `/agents` | Manage subagents |
| `/mcp` | Manage MCP servers |
| `/hooks` | View configured hooks |
| `/plugin` | Manage plugins |
| `/keybindings` | Configure custom keyboard shortcuts |
| `/skills` | View and manage skills |
| `/permissions` | View and manage permission rules |
| `--doctor` | Diagnose configuration issues |
| `--debug` | Debug mode with hook execution details |

---

## Quick Reference: Complete Example

```json
{
  "$schema": "https://json.schemastore.org/claude-code-settings.json",
  "model": "sonnet",
  "agent": "code-reviewer",
  "language": "english",
  "cleanupPeriodDays": 30,
  "autoUpdatesChannel": "stable",
  "alwaysThinkingEnabled": true,
  "showThinkingSummaries": true,
  "viewMode": "default",
  "includeGitInstructions": true,
  "defaultShell": "bash",
  "plansDirectory": "./plans",
  "effortLevel": "medium",

  "worktree": {
    "symlinkDirectories": ["node_modules"],
    "sparsePaths": ["packages/my-app", "shared/utils"]
  },

  "modelOverrides": {
    "claude-opus-4-6": "arn:aws:bedrock:us-east-1:123456789:inference-profile/anthropic.claude-opus-4-6-v1:0"
  },

  "autoMode": {
    "environment": [
      "Source control: github.example.com/acme-corp and all repos under it",
      "Trusted internal domains: *.internal.example.com"
    ]
  },

  "permissions": {
    "allow": [
      "Edit(*)",
      "Write(*)",
      "Bash(npm run *)",
      "Bash(git *)",
      "WebFetch(domain:*)",
      "mcp__*",
      "Agent(*)"
    ],
    "deny": [
      "Read(.env)",
      "Read(./secrets/**)"
    ],
    "additionalDirectories": ["../shared/"],
    "defaultMode": "acceptEdits"
  },

  "enableAllProjectMcpServers": true,

  "sandbox": {
    "enabled": true,
    "excludedCommands": ["git", "docker"],
    "filesystem": {
      "denyRead": ["./secrets/"],
      "denyWrite": ["./.env"]
    }
  },

  "attribution": {
    "commit": "Generated with Claude Code",
    "pr": ""
  },

  "statusLine": {
    "type": "command",
    "command": "git branch --show-current"
  },

  "spinnerTipsEnabled": true,
  "spinnerTipsOverride": {
    "tips": ["Custom tip 1", "Custom tip 2"],
    "excludeDefault": false
  },
  "prefersReducedMotion": false,

  "env": {
    "NODE_ENV": "development",
    "CLAUDE_CODE_EFFORT_LEVEL": "medium"
  }
}
```

---

## Sources

- [Claude Code Settings Documentation](https://code.claude.com/docs/en/settings)
- [Claude Code Settings JSON Schema](https://json.schemastore.org/claude-code-settings.json)
- [Claude Code Changelog](https://github.com/anthropics/claude-code/blob/main/CHANGELOG.md)
- [Claude Code GitHub Settings Examples](https://github.com/feiskyer/claude-code-settings)
- [Shipyard - Claude Code CLI Cheatsheet](https://shipyard.build/blog/claude-code-cheat-sheet/)
- [Claude Code Environment Variables Reference](https://code.claude.com/docs/en/env-vars)
- [Claude Code Permissions Reference](https://code.claude.com/docs/en/permissions)
