Reasoning modes

Control how the assistant reasons through questions with three modes: Auto, Instant, and Think.

Available modes

Mode	Description	Interactions per question
Auto (default)	Searches documentation using keywords and meaning. If it finds no usable documentation, tries keyword search once with the same question. If no supporting evidence is available, asks for more detail or documentation.	1
Instant	Searches documentation once using keywords and meaning, then writes the answer.	1
Think	Reviews results and can make additional focused searches and read fuller documentation pages before answering. Searches and review rounds are limited.	Up to 10

Auto does not automatically switch to Think. Choose Think for questions that may need information from several documentation sections. Additional searches do not guarantee a correct answer.

The interaction counts above cover the base documentation workflow. Enabling web search can add interactions.

These interactions count toward your team's included allowance. With extra usage enabled, interactions beyond that allowance cost $0.05 each.

All three modes show the current operation while answering. Progress disappears when the answer finishes. See Chat progress to choose between the default spinner and loading dots.

Enable reasoning modes

important

Only Administrator or Maintainer roles can manage projects. See Manage roles.

1. In the Biel.ai dashboard, select your project.

2. Click Settings.

3. Open Assistant in the left sidebar and find the AI model and instructions section.

4. Check Enable think mode.

   

5. Click Save on the AI model and instructions card.

Once enabled, users can select their preferred mode from the selector above the chat input. This includes the assistant opened through Ask AI in the search widget. The selection persists across page reloads.

Widget attributes

Control reasoning mode behavior with these attributes on <biel-button>, <biel-bot>, <biel-search-button>, or <biel-search>:

Attribute	Default	Description
default-think-mode	auto	Starting mode for a new visitor: auto, fast (shown as Instant), or think. A visitor's saved choice takes precedence.
think-mode-enabled	false	Legacy option to start in Think mode. default-think-mode takes precedence when both are set.
hide-settings-button	false	Hide the mode selector above the input. On <biel-search-button>, this also hides it after a visitor selects Ask AI from search results. An embedded <biel-bot> currently shows the selector whenever reasoning modes are enabled for the project.

Start new visitors in Think mode:

<biel-button
  project="my-project"
  default-think-mode="think"
>Ask AI</biel-button>

Hide the mode selector

You can combine default-think-mode with hide-settings-button to hide the selector. A visitor's previously saved choice still takes precedence over the default.

<biel-button
  project="my-project"
  default-think-mode="think"
  hide-settings-button="true"
>Ask AI</biel-button>