> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tinfoil.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# Chat settings

> Configure web search, Generative UI, reasoning, personalization, prompts, language, and other Tinfoil Chat behavior on web and iOS.

Tinfoil Chat separates global preferences from controls that apply to one conversation. Global preferences are available from Settings; model, prompt, and Web Search controls can also appear in the message composer.

<Tabs>
  <Tab title="Web app">
    Open the sidebar and select the **Settings** cog. Chat behavior is primarily under **Chat Settings**, **Personalization**, and **Prompts**.
  </Tab>

  <Tab title="iOS app">
    Open the sidebar and select **Settings**. Web Search and Generative UI are under **Preferences**. Language, prompts, and personalization are under **Chat Settings**.
  </Tab>
</Tabs>

## Web Search

Web Search lets the model retrieve current information while answering. It is on by default.

There are two controls:

* The global **Web Search** setting makes the feature available and sets the initial value for new chats.
* The per-chat **Web Search** control decides whether the current conversation can search.

Turning the global setting off forces Web Search off and hides its per-chat control. It does not erase the preference stored on an existing chat, so that preference is available again if you re-enable the global setting.

<Tabs>
  <Tab title="Web app">
    * Global setting: **Settings → Chat Settings → Advanced Settings → Web Search**
    * Current chat: open **Input options** in the composer and use **Web search**

    **Automatic PII Blocking in Web Search** is also under **Advanced Settings**.
  </Tab>

  <Tab title="iOS app">
    * Global setting: **Settings → Preferences → Web Search**
    * Current chat: tap **+ → Add to Chat → Chat Features → Web Search**

    **Automatic PII Blocking in Web Search** is under **Preferences**.
  </Tab>
</Tabs>

When Automatic PII Blocking is enabled, web-search requests include an automatic PII check. It is on by default on both platforms.

For cloud chats, the stored per-chat preference is encrypted with the chat. Local-only web chats keep it in the browser-local chat record, which Tinfoil Chat does not additionally encrypt; see [local-only chats](/chat/data-controls#local-only-chats). The global availability setting can force the effective value off without changing that stored preference. The global setting is part of your encrypted profile when cloud sync is active.

## Generative UI

**Generative UI** (GenUI) allows the assistant to return interactive widgets, such as charts and timelines, instead of text alone. It is on by default and applies globally rather than per chat.

<Tabs>
  <Tab title="Web app">
    Go to **Settings → Chat Settings → Advanced Settings → Generative UI**.
  </Tab>

  <Tab title="iOS app">
    Go to **Settings → Preferences → Generative UI**.
  </Tab>
</Tabs>

When enabled, new requests can use interactive widgets. When disabled, the app does not send those tool capabilities. Disabling Generative UI does not remove widgets already saved in conversations.

<Note>
  Some models do not support tool use. When you use **Auto**, Tinfoil Chat
  prefers a compatible model when Generative UI is enabled and one is
  available.
</Note>

## Reasoning and thinking

Reasoning controls are model-dependent rather than a Settings row.

<Tabs>
  <Tab title="Web app">
    Open the model selector. Supported models show **Effort** with **Low**, **Medium**, and **High** and, when supported, a **Thinking** switch.
  </Tab>

  <Tab title="iOS app">
    Use the control beside the model selector. Effort models show **Low**, **Medium**, and **High**, plus **Off** when supported. Toggle-only models show **On** and **Off**.
  </Tab>
</Tabs>

**Medium** effort and enabled thinking are the defaults. Models that do not advertise a reasoning capability do not show these controls.

Higher effort can produce a more thorough response but usually takes longer. The reasoning preference is global and encrypted in your synced profile, but Tinfoil Chat applies it only when the selected model supports it.

<Note>
  On iOS, **Auto** tiers do not expose reasoning controls because they do not
  represent one model with a fixed reasoning configuration.
</Note>

## Personalization

Personalization adds information about you to the model context. It is encrypted with your profile when cloud sync is enabled.

<Tabs>
  <Tab title="Web app">
    Go to **Settings → Personalization**. You can set **Name**, **Occupation**, **Conversational Traits**, and **Additional Context**, then select **Save**.

    Use **Personalize responses** to turn profile insertion on or off. Turning it off keeps the saved fields but stops adding them to new requests.
  </Tab>

  <Tab title="iOS app">
    Go to **Settings → Chat Settings → Personalization**. You can set a nickname, profession, conversational traits, and additional context, then select **Save**.

    Use **Personalize responses** to turn profile insertion on or off. Turning it off keeps the saved fields but stops adding them to new requests. Select **Clear details**, then **Save**, to remove the saved personalization fields.
  </Tab>
</Tabs>

Personalization is on by default when no preference has been saved. An explicit off setting is encrypted and synced with your profile.

## System prompts and prompt presets

A system prompt changes how the assistant behaves. You can set a global default or select a preset for one chat.

The precedence is:

1. The prompt preset selected for the current chat
2. Your custom default system prompt
3. Tinfoil Chat's built-in default

<Tabs>
  <Tab title="Web app">
    * **Settings → Prompts → Default System Prompt** sets the custom default.
    * **Built-in Prompts** and **Your Prompts** manage the prompt library.
    * In the composer, open **Input options → Change system prompt** to select a preset for the current chat.

    Custom default prompts and prompt presets support `{USER_PREFERENCES}`, `{LANGUAGE}`, and `{TIMEZONE}` placeholders.
  </Tab>

  <Tab title="iOS app">
    * **Settings → Chat Settings → Custom System Prompt** sets the custom default.
    * **Settings → Chat Settings → Prompts** opens the prompt library.
    * Select **Use for this chat** or **Stop using** from a prompt to change the current chat.

    Custom prompts and presets support `{USER_PREFERENCES}`, `{LANGUAGE}`, and `{TIMEZONE}` placeholders.
  </Tab>
</Tabs>

Custom prompts, prompt presets, and favorites are encrypted in your synced profile. The selected preset syncs with the chat.

## Language, appearance, and chat font

<Tabs>
  <Tab title="Web app">
    * **Settings → General → Appearance → Theme**: **Light**, **Dark**, or **System**
    * **Settings → Chat Settings → Conversation Settings → Chat font**: **System**, **Serif**, **Mono**, or **Dyslexic friendly**
    * **Response Language** in **Conversation Settings** controls the language requested from the model.
  </Tab>

  <Tab title="iOS app">
    * **Settings → Chat Settings → Response Language** controls the language requested from the model.
    * Appearance follows the device color scheme. Theme and chat-font settings are available only on web.
  </Tab>
</Tabs>

Both platforms provide **System**, which resolves the current browser or device language when a request is sent. The literal word `System` is never sent to the model.

## Model selection

Model selection is not a Settings row. Use the model button in the message composer to select a model or an **Auto** tier.

Tinfoil Chat remembers a device-local fallback model for new chats. Saved web chats retain their selected model. On iOS, downloaded chats use the model selected on that device. When available, the initial default is **Auto · Fast**.

## What syncs across devices

With cloud sync enabled, Tinfoil Chat encrypts and syncs these profile settings:

* Web Search availability and automatic PII checking
* Generative UI
* Reasoning and thinking preferences
* Language
* Personalization
* Custom prompts, prompt presets, and favorites
* Web theme and chat font

The active prompt preset and Web Search preference are stored with the chat. Web also stores the selected model with the chat; iOS cloud sync does not.

The fallback model for new chats and the **Enable local chats** preference remain device-local. Settings available only on web remain unchanged when you use iOS.

See [cloud sync and encryption](/chat/cloud-sync) for how settings are protected, and [data controls and deletion](/chat/data-controls) for local and temporary chat options.