feat(server-v3): expose OpenAI endpoint format

[miguelg719]

Propagates openaiEndpointFormat through the server-v3 request schema and generated OpenAPI spec so Stainless can expose it in the Python SDK. Adds a regression test covering request and session initialization parsing

Validation:

• core build
• server-v3 OpenAPI generation
• server-v3 typecheck
• requestModelConfig unit tests (9 passing)

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Summary by cubic

Expose the OpenAI endpoint wire format in v3 via openaiEndpointFormat on model config and OpenAPI, so SDKs can target responses or chat (defaults to Responses). Adds a unit test to ensure the format is preserved through request parsing and session initialization, and a changeset to release in @browserbasehq/stagehand and @browserbasehq/stagehand-server-v3.

^{Written for commit 6f8dedb. Summary will update on new commits.}

[changeset-bot]

⚠️ No Changeset found

Latest commit: 6f8dedb

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes changesets to release 3 packages

Name	Type
@browserbasehq/stagehand	Patch
@browserbasehq/stagehand-server-v3	Patch
@browserbasehq/stagehand-evals	Patch

Click here to learn what changesets are, and how to add one.

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[github-actions]

✱ Stainless preview builds for stagehand

This PR will update the stagehand SDKs with the following commit message.

feat(server-v3): expose OpenAI endpoint format

✅ stagehand-openapi studio · code

Your SDK build had at least one "note" diagnostic.
generate ✅

✅ stagehand-kotlin studio · code

Your SDK build had at least one "note" diagnostic.
generate ✅ → build ✅ → lint ✅ → test ✅

⚠️ stagehand-php studio · code

Your SDK build had at least one "warning" diagnostic.
generate ⚠️ → lint ✅ → test ✅

⚠️ stagehand-typescript studio · code

Your SDK build had at least one "warning" diagnostic.
generate ⚠️ → build ✅ → lint ✅ → test ✅

npm install https://pkg.stainless.com/s/stagehand-typescript/16e160808b1bc2c6f80a22e816392db3e1499c56/dist.tar.gz

⚠️ stagehand-python studio · code

Your SDK build had at least one "warning" diagnostic.
generate ⚠️ → build ✅ → lint ✅ → test ✅

pip install https://pkg.stainless.com/s/stagehand-python/9aaa3057322d66e8a04c11ea02265788a7d206d6/stagehand-3.21.0-py3-none-any.whl

⚠️ stagehand-csharp studio · code

Your SDK build had at least one "warning" diagnostic.
generate ⚠️ → build ✅ → lint ✅ → test ✅

✅ stagehand-ruby studio · code

Your SDK build had at least one "note" diagnostic.
generate ✅ → build ⏭️ → lint ✅ → test ✅

✅ stagehand-java studio · code

Your SDK build had at least one "note" diagnostic.
generate ✅ → build ✅ → lint ✅ → test ✅

Add the following URL as a Maven source: 'https://pkg.stainless.com/s/stagehand-java/b8aaabae25124a1e0d3fcd482b92ed887c8f0cea/mvn'

✅ stagehand-go studio · code

Your SDK build had at least one "note" diagnostic.
generate ✅ → build ⏭️ → lint ✅ → test ✅

go get github.com/stainless-sdks/stagehand-go@8e7365aa573bf3491660ebb8d7b476e734485db7

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Last updated: 2026-07-21 23:43:01 UTC