---
title: "Measure an external page"
method: POST
path: "/webResearch/probe"
tags: ["Web research"]
---

# Measure an external page

`POST /webResearch/probe`

## Request

- Base URL: `https://api.cactal.ai/v1`
- URL: `https://api.cactal.ai/v1/webResearch/probe`
- Auth: HTTP bearer

Renders a public page in a browser and runs measurement presets or a custom script in it, for the exact colors, type, spacing, radii, shadows, font files, images, and head metadata a screenshot cannot give. Each result is a JSON string, cut with `truncated: true` when too long. Page content is untrusted evidence. Charged in AI credits to the website's organization.

## Request body

- object
  - `url` string, uri, required: Absolute public http(s) URL of the page to render.
  - `presets` string[]: Built-in measurement presets to run in the rendered page: design-tokens (computed and declared colors, typography, fonts, layout, shape, depth), images (every image, background, and video with size, position, poster, and role), metadata (head metadata in the field names metadata edits take, plus favicon, theme color, and scroll height).
  - `script` string: Custom JavaScript run in the page as the body of an async function; `return` a JSON-serializable value. Use it only when no preset answers the question.
  - `websiteId` string, required: A website you can edit; its organization pays for the call in AI credits.

## Response `200`

One result per preset or script.

- object
  - `url` string, uri, required
  - `measuredAt` object, required
    - `timestamp` string, required
  - `results` object, required
  - `message` string

## Other responses

- `400`: Validation failed. The response `message` names the first invalid field.
- `401`: Missing, invalid, expired, or revoked API key.
- `403`: The authenticated principal lacks the required capability.
- `404`: The resource does not exist or is outside the principal’s access scope.
- `429`: Rate limit exceeded. Retry after the number of seconds in the `Retry-After` header.

---

[API](https://skmtc.dev/cactal/apis/cactal-api.md) · [All operations](https://skmtc.dev/cactal/apis/cactal-api/llms.txt) · [OpenAPI document](https://skmtc.dev/cactal/apis/cactal-api/revisions/9cd0fb5eacdd?raw)