Use this example configuration as a starting point. It includes most keys Codex reads from config.toml, along with defaults and short notes.
For explanations and guidance, see:
Use the snippet below as a reference. Copy only the keys and sections you need into ~/.codex/config.toml (or into a project-scoped .codex/config.toml), then adjust values for your setup.
# Codex example configuration (config.toml)
#
# This file lists all keys Codex reads from config.toml, their default values,
# and concise explanations. Values here mirror the effective defaults compiled
# into the CLI. Adjust as needed.
#
# Notes
# - Root keys must appear before tables in TOML.
# - Optional keys that default to "unset" are shown commented out with notes.
# - MCP servers, profiles, and model providers are examples; remove or edit.
################################################################################
# Core Model Selection
################################################################################
# Primary model used by Codex. Default: "gpt-5.2-codex" on all platforms.
model = "gpt-5.2-codex"
# Optional model override for /review. Default: unset (uses current session model).
# review_model = "gpt-5.2-codex"
# Provider id selected from [model_providers]. Default: "openai".
model_provider = "openai"
# Default OSS provider for --oss sessions. When unset, Codex prompts. Default: unset.
# oss_provider = "ollama"
# Optional manual model metadata. When unset, Codex auto-detects from model.
# Uncomment to force values.
# model_context_window = 128000 # tokens; default: auto for model
# model_auto_compact_token_limit = 0 # tokens; unset uses model defaults
# tool_output_token_limit = 10000 # tokens stored per tool output; default: 10000 for gpt-5.2-codex
################################################################################
# Reasoning & Verbosity (Responses API capable models)
################################################################################
# Reasoning effort: minimal | low | medium | high | xhigh (default: medium; xhigh on gpt-5.2-codex and gpt-5.2)
model_reasoning_effort = "medium"
# Reasoning summary: auto | concise | detailed | none (default: auto)
model_reasoning_summary = "auto"
# Text verbosity for GPT-5 family (Responses API): low | medium | high (default: medium)
model_verbosity = "medium"
# Force-enable reasoning summaries for current model (default: false)
model_supports_reasoning_summaries = false
################################################################################
# Instruction Overrides
################################################################################
# Additional user instructions are injected before AGENTS.md. Default: unset.
# developer_instructions = ""
# (Ignored) Optional legacy base instructions override (prefer AGENTS.md). Default: unset.
# instructions = ""
# Inline override for the history compaction prompt. Default: unset.
# compact_prompt = ""
# Override built-in base instructions with a file path. Default: unset.
# model_instructions_file = "/absolute/or/relative/path/to/instructions.txt"
# Migration note: experimental_instructions_file was renamed to model_instructions_file (deprecated).
# Load the compact prompt override from a file. Default: unset.
# experimental_compact_prompt_file = "/absolute/or/relative/path/to/compact_prompt.txt"
################################################################################
# Notifications
################################################################################
# External notifier program (argv array). When unset: disabled.
# Example: notify = ["notify-send", "Codex"]
notify = [ ]
################################################################################
# Approval & Sandbox
################################################################################
# When to ask for command approval:
# - untrusted: only known-safe read-only commands auto-run; others prompt
# - on-failure: auto-run in sandbox; prompt only on failure for escalation
# - on-request: model decides when to ask (default)
# - never: never prompt (risky)
approval_policy = "on-request"
# Filesystem/network sandbox policy for tool calls:
# - read-only (default)
# - workspace-write
# - danger-full-access (no sandbox; extremely risky)
sandbox_mode = "read-only"
################################################################################
# Authentication & Login
################################################################################
# Where to persist CLI login credentials: file (default) | keyring | auto
cli_auth_credentials_store = "file"
# Base URL for ChatGPT auth flow (not OpenAI API). Default:
chatgpt_base_url = "https://chatgpt.com/backend-api/"
# Restrict ChatGPT login to a specific workspace id. Default: unset.
# forced_chatgpt_workspace_id = ""
# Force login mechanism when Codex would normally auto-select. Default: unset.
# Allowed values: chatgpt | api
# forced_login_method = "chatgpt"
# Preferred store for MCP OAuth credentials: auto (default) | file | keyring
mcp_oauth_credentials_store = "auto"
# Optional fixed port for MCP OAuth callback: 1-65535. Default: unset.
# mcp_oauth_callback_port = 4321
################################################################################
# Project Documentation Controls
################################################################################
# Max bytes from AGENTS.md to embed into first-turn instructions. Default: 32768
project_doc_max_bytes = 32768
# Ordered fallbacks when AGENTS.md is missing at a directory level. Default: []
project_doc_fallback_filenames = []
# Project root marker filenames used when searching parent directories. Default: [".git"]
# project_root_markers = [".git"]
################################################################################
# History & File Opener
################################################################################
# URI scheme for clickable citations: vscode (default) | vscode-insiders | windsurf | cursor | none
file_opener = "vscode"
################################################################################
# UI, Notifications, and Misc
################################################################################
# Suppress internal reasoning events from output. Default: false
hide_agent_reasoning = false
# Show raw reasoning content when available. Default: false
show_raw_agent_reasoning = false
# Disable burst-paste detection in the TUI. Default: false
disable_paste_burst = false
# Track Windows onboarding acknowledgement (Windows only). Default: false
windows_wsl_setup_acknowledged = false
# Check for updates on startup. Default: true
check_for_update_on_startup = true
################################################################################
# Web Search
################################################################################
# Web search mode: disabled | cached | live. Default: "cached"
# cached serves results from a web search cache (an OpenAI-maintained index).
# cached returns pre-indexed results; live fetches the most recent data.
# If you use --yolo or another full access sandbox setting, web search defaults to live.
web_search = "cached"
################################################################################
# Profiles (named presets)
################################################################################
# Active profile name. When unset, no profile is applied.
# profile = "default"
################################################################################
# Skills (per-skill overrides)
################################################################################
# Disable or re-enable a specific skill without deleting it.
[[skills.config]]
# path = "/path/to/skill"
# enabled = false
################################################################################
# Experimental toggles (legacy; prefer [features])
################################################################################
experimental_use_unified_exec_tool = false
# Include apply_patch via freeform editing path (affects default tool set). Default: false
experimental_use_freeform_apply_patch = false
################################################################################
# Sandbox settings (tables)
################################################################################
# Extra settings used only when sandbox_mode = "workspace-write".
[sandbox_workspace_write]
# Additional writable roots beyond the workspace (cwd). Default: []
writable_roots = []
# Allow outbound network access inside the sandbox. Default: false
network_access = false
# Exclude $TMPDIR from writable roots. Default: false
exclude_tmpdir_env_var = false
# Exclude /tmp from writable roots. Default: false
exclude_slash_tmp = false
################################################################################
# Shell Environment Policy for spawned processes (table)
################################################################################
[shell_environment_policy]
# inherit: all (default) | core | none
inherit = "all"
# Skip default excludes for names containing KEY/SECRET/TOKEN (case-insensitive). Default: true
ignore_default_excludes = true
# Case-insensitive glob patterns to remove (e.g., "AWS_*", "AZURE_*"). Default: []
exclude = []
# Explicit key/value overrides (always win). Default: {}
set = {}
# Whitelist; if non-empty, keep only matching vars. Default: []
include_only = []
# Experimental: run via user shell profile. Default: false
experimental_use_profile = false
################################################################################
# History (table)
################################################################################
[history]
# save-all (default) | none
persistence = "save-all"
# Maximum bytes for history file; oldest entries are trimmed when exceeded. Example: 5242880
# max_bytes = 0
################################################################################
# UI, Notifications, and Misc (tables)
################################################################################
[tui]
# Desktop notifications from the TUI: boolean or filtered list. Default: true
# Examples: false | ["agent-turn-complete", "approval-requested"]
notifications = false
# Enables welcome/status/spinner animations. Default: true
animations = true
# Show onboarding tooltips in the welcome screen. Default: true
show_tooltips = true
# Control alternate screen usage (auto skips it in Zellij to preserve scrollback).
# alternate_screen = "auto"
# Control whether users can submit feedback from `/feedback`. Default: true
[feedback]
enabled = true
# In-product notices (mostly set automatically by Codex).
[notice]
# hide_full_access_warning = true
# hide_world_writable_warning = true
# hide_rate_limit_model_nudge = true
# hide_gpt5_1_migration_prompt = true
# "hide_gpt-5.1-codex-max_migration_prompt" = true
# model_migrations = { "gpt-4.1" = "gpt-5.1" }
# Suppress the warning shown when under-development feature flags are enabled.
# suppress_unstable_features_warning = true
################################################################################
# Centralized Feature Flags (preferred)
################################################################################
[features]
# Leave this table empty to accept defaults. Set explicit booleans to opt in/out.
shell_tool = true
# Deprecated legacy toggles; prefer the top-level `web_search` setting.
# web_search_cached = false
# web_search_request = false
unified_exec = false
shell_snapshot = false
apply_patch_freeform = false
exec_policy = true
experimental_windows_sandbox = false
elevated_windows_sandbox = false
remote_compaction = true
remote_models = false
powershell_utf8 = true
child_agents_md = false
################################################################################
# Define MCP servers under this table. Leave empty to disable.
################################################################################
[mcp_servers]
# --- Example: STDIO transport ---
# [mcp_servers.docs]
# enabled = true # optional; default true
# command = "docs-server" # required
# args = ["--port", "4000"] # optional
# env = { "API_KEY" = "value" } # optional key/value pairs copied as-is
# env_vars = ["ANOTHER_SECRET"] # optional: forward these from the parent env
# cwd = "/path/to/server" # optional working directory override
# startup_timeout_sec = 10.0 # optional; default 10.0 seconds
# # startup_timeout_ms = 10000 # optional alias for startup timeout (milliseconds)
# tool_timeout_sec = 60.0 # optional; default 60.0 seconds
# enabled_tools = ["search", "summarize"] # optional allow-list
# disabled_tools = ["slow-tool"] # optional deny-list (applied after allow-list)
# --- Example: Streamable HTTP transport ---
# [mcp_servers.github]
# enabled = true # optional; default true
# url = "https://github-mcp.example.com/mcp" # required
# bearer_token_env_var = "GITHUB_TOKEN" # optional; Authorization: Bearer <token>
# http_headers = { "X-Example" = "value" } # optional static headers
# env_http_headers = { "X-Auth" = "AUTH_ENV" } # optional headers populated from env vars
# startup_timeout_sec = 10.0 # optional
# tool_timeout_sec = 60.0 # optional
# enabled_tools = ["list_issues"] # optional allow-list
################################################################################
# Model Providers
################################################################################
# Built-ins include:
# - openai (Responses API; requires login or OPENAI_API_KEY via auth flow)
# - oss (Chat Completions API; defaults to http://localhost:11434/v1)
[model_providers]
# --- Example: OpenAI data residency with explicit base URL or headers ---
# [model_providers.openaidr]
# name = "OpenAI Data Residency"
# base_url = "https://us.api.openai.com/v1" # example with 'us' domain prefix
# wire_api = "responses" # "responses" | "chat" (default varies)
# # requires_openai_auth = true # built-in OpenAI defaults to true
# # request_max_retries = 4 # default 4; max 100
# # stream_max_retries = 5 # default 5; max 100
# # stream_idle_timeout_ms = 300000 # default 300_000 (5m)
# # experimental_bearer_token = "sk-example" # optional dev-only direct bearer token
# # http_headers = { "X-Example" = "value" }
# # env_http_headers = { "OpenAI-Organization" = "OPENAI_ORGANIZATION", "OpenAI-Project" = "OPENAI_PROJECT" }
# --- Example: Azure (Chat/Responses depending on endpoint) ---
# [model_providers.azure]
# name = "Azure"
# base_url = "https://YOUR_PROJECT_NAME.openai.azure.com/openai"
# wire_api = "responses" # or "chat" per endpoint
# query_params = { api-version = "2025-04-01-preview" }
# env_key = "AZURE_OPENAI_API_KEY"
# # env_key_instructions = "Set AZURE_OPENAI_API_KEY in your environment"
# --- Example: Local OSS (e.g., Ollama-compatible) ---
# [model_providers.ollama]
# name = "Ollama"
# base_url = "http://localhost:11434/v1"
# wire_api = "chat"
################################################################################
# Profiles (named presets)
################################################################################
[profiles]
# [profiles.default]
# model = "gpt-5.2-codex"
# model_provider = "openai"
# approval_policy = "on-request"
# sandbox_mode = "read-only"
# oss_provider = "ollama"
# model_reasoning_effort = "medium"
# model_reasoning_summary = "auto"
# model_verbosity = "medium"
# chatgpt_base_url = "https://chatgpt.com/backend-api/"
# experimental_compact_prompt_file = "./compact_prompt.txt"
# include_apply_patch_tool = false
# experimental_use_unified_exec_tool = false
# experimental_use_freeform_apply_patch = false
# tools_web_search = false # deprecated legacy alias; prefer `web_search`
# features = { unified_exec = false }
################################################################################
# Projects (trust levels)
################################################################################
# Mark specific worktrees as trusted or untrusted.
[projects]
# [projects."/absolute/path/to/project"]
# trust_level = "trusted" # or "untrusted"
################################################################################
# OpenTelemetry (OTEL) - disabled by default
################################################################################
[otel]
# Include user prompt text in logs. Default: false
log_user_prompt = false
# Environment label applied to telemetry. Default: "dev"
environment = "dev"
# Exporter: none (default) | otlp-http | otlp-grpc
exporter = "none"
# Trace exporter: none (default) | otlp-http | otlp-grpc
trace_exporter = "none"
# Example OTLP/HTTP exporter configuration
# [otel.exporter."otlp-http"]
# endpoint = "https://otel.example.com/v1/logs"
# protocol = "binary" # "binary" | "json"
# [otel.exporter."otlp-http".headers]
# "x-otlp-api-key" = "${OTLP_TOKEN}"
# Example OTLP/gRPC exporter configuration
# [otel.exporter."otlp-grpc"]
# endpoint = "https://otel.example.com:4317",
# headers = { "x-otlp-meta" = "abc123" }
# Example OTLP exporter with mutual TLS
# [otel.exporter."otlp-http"]
# endpoint = "https://otel.example.com/v1/logs"
# protocol = "binary"
# [otel.exporter."otlp-http".headers]
# "x-otlp-api-key" = "${OTLP_TOKEN}"
# [otel.exporter."otlp-http".tls]
# ca-certificate = "certs/otel-ca.pem"
# client-certificate = "/etc/codex/certs/client.pem"
# client-private-key = "/etc/codex/certs/client-key.pem"