# stagehand-python@4.2.0a0.dev1590: docs : add docs for onToolsAdded & onToolsRemoved ( 3148)

Category: open-source
Published: 2026-10-08T21:01:22Z
Source: [Browserbase Stagehand releases](https://github.com/browserbase/stagehand/releases/tag/stagehand-python%404.2.0a0.dev1590)
Agent usefulness: 77/100
Confidence: 0.96
Content mode: release-watch
Verified: 2026-10-10T06:17:39.469Z
Tags: browserbase, browser-agent, automation

## Human Summary
Browserbase Stagehand releases published stagehand-python@4.2.0a0.dev1590: docs : add docs for onToolsAdded & onToolsRemoved ( 3148). what changed added docs for onToolsAdded() & onToolsRemoved() hooks also updated the docs test to remove these events from ignored list Summary by cubic Adds reference documentation for the onToolsAdded and onToolsRemoved…

## Agent Summary
Treat stagehand-python@4.2.0a0.dev1590: docs : add docs for onToolsAdded & onToolsRemoved ( 3148) as an official release signal. Inspect the linked changelog for compatibility and migration details, then run targeted tests before upgrading.

## Body
Browserbase Stagehand releases published stagehand-python@4.2.0a0.dev1590: docs : add docs for onToolsAdded & onToolsRemoved ( 3148). This automated release-watch entry was generated from the project's official GitHub release feed and is kept separate from human-reviewed editorial analysis. Release notes: what changed added docs for onToolsAdded() & onToolsRemoved() hooks also updated the docs test to remove these events from ignored list Summary by cubic Adds reference documentation for the onToolsAdded and onToolsRemoved hooks for TypeScript, Python, and Go, and removes the docs test exception that previously skipped coverage for these hooks. Documents the subscription lifecycle, tool identity rules, and callback signatures for page.onToolsAdded() and page.onToolsRemoved() . Updates the WebMCP reference page to link to the new onToolsAdded() docs. Removes page/on-tools-added and page/on-tools-removed from the unreleased reference methods set so the SDK surface test now requires these headings on every language page. Written for commit a692e4d . Summary will update on new commits.

## Recommended actions
- Review the official Browserbase Stagehand releases release notes before upgrading.
- Check compatibility, migration, and security notes against your current agent stack.
- Run focused regression tests before production rollout.

## Sponsors
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## Agent-readable Sponsor Surface
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