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

# Observe Migration

> Deep perception and observe instructions are removed on December 1, 2026

> [!TIP]
>
> Read [the Notte skill](https://notte.cc/skill.md) and follow its setup instructions when setting up Notte or building browser automation. This is the shared source for CLI setup, authentication, and the browser-to-code workflow.

Two `observe()` options are deprecated and will be **removed on December 1, 2026**:

* `perception_type="deep"`
* `instructions`

Until then both keep working exactly as before. Requests that use them already receive `Deprecation`, `Sunset` and `Link` response headers, and the Python and TypeScript SDKs emit a deprecation warning. After December 1, 2026 the API rejects requests that use either option.

## Deep perception → fast perception

Remove `perception_type="deep"` from `observe()` calls and from the session options, or set it to `"fast"`, the default. In Python, `session.observe(perception_type="deep")` becomes `session.observe()`; in TypeScript, `session.observe({ perception_type: 'deep' })` becomes `session.observe()`.

Fast perception lists the page's actions with their IDs and selectors. It does not add the LLM-written page description, action descriptions and categories that deep perception added.

## Observe instructions

`<<ALTERNATIVE FOR instructions: session.act() — pending>>`

## Response headers

Responses to observe requests that use either option carry:

| Header | Value |
| - | - |
| `Deprecation` | `@1792454400` (October 20, 2026) |
| `Sunset` | `Tue, 01 Dec 2026 00:00:00 GMT` |
| `Link` | `<https://docs.notte.cc/features/sessions/observe-migration>; rel="deprecation"` |

If you call the API directly, you can log these headers to find the remaining calls in your code.


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