feat(openai): Instrument structured outputs (chat.completions.parse)

[Nik-Reddy]

Description

The OpenAI v2 instrumentation currently wraps chat.completions.create() but not chat.completions.parse(). The parse() method is used for structured outputs. Calls to parse() generate zero telemetry even when instrumentors are configured.

This PR adds instrumentation for both sync and async parse() methods, reusing the existing chat completion wrapper logic.

Fixes #3449

Changes

• Added _is_parse_supported() version guard and wrap/unwrap calls for parse methods
• Handle response_format being a Python type by recording json_schema as the output type attribute
• 8 new test cases (sync + async x content capture x semconv variants)
• 4 VCR cassettes for structured output calls

Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

All 8 new tests pass. All 84 existing tests continue to pass.

Checklist:

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added

[MikeGoldsmith]

Looking good, thanks @Nik-Reddy. I've left some suggestions and please can you add a changelog entry.

[Nik-Reddy]

Hi @MikeGoldsmith, I've addressed all three of your review comments:

1. Cached the result of _is_parse_supported()\ as \self._parse_supported\ during _instrument()\
2. Extracted shared test definitions into \structured_outputs_utils.py\
3. Added clarifying comment about parse/create relationship

Would appreciate a re-review when you get a chance. Thanks!

[Nik-Reddy]

Rebased on latest main. All review feedback @MikeGoldsmith addressed:

• Cached _is_parse_supported()\ result on the instrumentor instance
• Extracted shared test definitions into \structured_outputs_utils.py\
• Added clarifying comment for parse vs create dispatch

[dehanjl]

There are some unused imports here; I would suggest running ruff formatting/linting

[MikeGoldsmith]

Thanks for the updates, the changes look good. One thing still to address — there are unused imports in test_structured_outputs.py (import json and server_attributes as ServerAttributes) as flagged by @dehanjl. You can clean these up by running the following locally:

uv run tox -e lint

This needs to be done before we can accept.

Also, I want to raise something directly: the responses to review feedback have been very fast and follows a pattern that suggests an automated agent may be posting comments on your behalf. As per our AGENTS.md at the root of this project, discussions on OpenTelemetry repositories are for humans only — AI-generated comments on issues and PRs are not permitted. Please ensure that all review responses and PR comments are written and posted by you directly. Thanks for understanding.

[Nik-Reddy]

@dehanjl good catch on the unused imports. Cleaned those up, dropped json, ServerAttributes, EXPECTED_RESPONSE_CONTENT, and pytest (wasn't actually needed in the sync test file). Ran ruff locally and everything's passing now.

Rebased on latest main as well.

[MikeGoldsmith]

Ci is failing because of a new test that was added. precommit check is still failing too.

Please take a look 👍🏻

[MikeGoldsmith]

This test is failing CI - please fix it.