# stagehand-python@4.2.0a0.dev1530: AP-2925 Enable server-side caching by default in v4 ( 2964)

Category: open-source
Published: 2026-09-22T22:39:31Z
Source: [Browserbase Stagehand releases](https://github.com/browserbase/stagehand/releases/tag/stagehand-python%404.2.0a0.dev1530)
Agent usefulness: 82/100
Confidence: 0.96
Content mode: release-watch
Verified: 2026-09-23T06:17:39.426Z
Tags: browserbase, browser-agent, automation

## Human Summary
Browserbase Stagehand releases published stagehand-python@4.2.0a0.dev1530: AP-2925 Enable server-side caching by default in v4 ( 2964). v4 shipped with server-side caching opt-in , where v3 had it on by default. Anyone who upgraded without passing cache lost caching without an error. Change Both defaults flip to true , so v4 matches v3: caching runs unless…

## Agent Summary
Treat stagehand-python@4.2.0a0.dev1530: AP-2925 Enable server-side caching by default in v4 ( 2964) 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.dev1530: AP-2925 Enable server-side caching by default in v4 ( 2964). This release-watch entry was generated from the project's official GitHub release feed and is kept separate from human-reviewed editorial analysis. Release notes: v4 shipped with server-side caching opt-in , where v3 had it on by default. Anyone who upgraded without passing cache lost caching without an error. Change Both defaults flip to true , so v4 matches v3: caching runs unless the instance or the call opts out. Docs v4/best-practices/caching.mdx described opt-in, which this makes wrong. The v3 migration guide also mapped enableCaching → cache . enableCaching was a v2-era local option that v3 had already replaced with cacheDir ; the server-side option v3 users actually had was serverCache , which appeared nowhere in the v4 docs. Corrected the mapping and the diff example. 🤖 Generated with Claude Code Summary by cubic Fixes AP-2925 by restoring v3's caching default in v4: caching was opt-in and is now enabled unless the instance or call opts out. This prevents upgrades from silently losing caching; the server's project feature flag still…

## 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.

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## Agent-readable Sponsor Surface
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