release: 0.53.0

[stainless-app]

Automated Release PR

0.53.0 (2026-05-12)

Full Changelog: v0.52.0...v0.53.0

Features

• Add 'switch' MFA option type for generic method-switcher links (82ae224)
• api: server-side search on GET /projects (cacb057)
• browser_pools: add start_url config (KERNEL-1217 PR 2) (e3f0b8d)
• internal/types: support eagerly validating pydantic iterators (b30bc1e)
• managed-auth: surface awaiting_external_action even when fallback actions exist (fd4ffe4)
• Scope name uniqueness to project for profiles, session_pools, extensions, credentials (c510a51)

Bug Fixes

• client: add missing f-string prefix in file type error message (fb5340d)

Chores

• internal: reformat pyproject.toml (27c799b)

---

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The semver version number is based on included commit messages. Alternatively, you can manually set the version number in the title of this pull request.

For a better experience, it is recommended to use either rebase-merge or squash-merge when merging this pull request.

🔗 Stainless website
📚 Read the docs
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---

Note

Medium Risk
Moderate risk: adds new request/response fields and query params in generated client APIs and introduces custom Pydantic v2 validation/serialization logic for iterables, which could affect model parsing/serialization behavior.

Overview
Bumps the SDK to 0.53.0 and updates release metadata/changelog and OpenAPI spec pointers.

Adds new API surface area: start_url support for creating/updating browser pools and creating browsers (plumbed through resource methods and associated param/response types), and a query filter for GET /projects list.

Expands managed-auth types to include a new MFA option kind switch and clarifies that various fallback action fields may be present during external action steps.

Fixes a TypeError message in _files.py (missing f-string) and introduces EagerIterable (Pydantic v2) to eagerly consume/validate Iterable inputs to avoid iterator consumption issues, with new tests covering the behavior.

^{Reviewed by Cursor Bugbot for commit df361ab. Bugbot is set up for automated code reviews on this repo. Configure here.}

[firetiger-agent]

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[stainless-app]

🧪 Testing

To try out this version of the SDK:

pip install 'https://pkg.stainless.com/s/kernel-python/fd4ffe40e037e95e93f46b7773d6a5e468c7b8fd/kernel-0.52.0-py3-none-any.whl'

Expires at: Thu, 11 Jun 2026 19:37:09 GMT
Updated at: Tue, 12 May 2026 19:37:09 GMT

[stainless-app]

Release version edited manually

The Pull Request version has been manually set to 0.52.1 and will be used for the release.

If you instead want to use the version number 0.53.0 generated from conventional commits, just remove the label autorelease: custom version from this Pull Request.