A CLI-internal update_settings tool lets host UIs write settings the way /config does, for now only outputStyle in project local settings.
A new CLI-internal update_settings tool lets host UIs merge settings into a settings file through the CLI's own writer, covering the canonical store, gitignore upkeep, and hardened writes, and live-applies them, mirroring what /config does. For now only the project's local settings file is supported and only the outputStyle key is allowlisted; it requires string values, refuses remote transports, and refuses sessions whose --setting-sources exclude the target file.
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
* A session where your organization's managed settings [lock skills to plugin sources](/docs/en/settings-reference#strictpluginonlycustomization-skills), or one you start with a [`--setting-sources`](/docs/en/cli-reference#cli-flags) list …skills see the edit
In the Python SDK, set `outputStyle` through the `settings` option, which takes a JSON string such as `'{"outputStyle": "Explanatory"}'` or a path to a settings file that sets it.agent-sdk/modifying-system-prompts see the edit
When you switch [output styles](/docs/en/output-styles) mid-session with `/config` or the `outputStyle` setting, Claude uses the new style starting with your next message. Claude Code delivers the new style's instructions as a message in t…prompt-caching see the edit
Anthropic's documentation has since written up outputStyle, on How Claude Code uses prompt caching.