[Bugfix] Fix Qwen3-VL-Reranker load.

[noooop]

Purpose

Fix Qwen3-VL-Reranker load.

Test Plan

tests/entrypoints/pooling/score/test_online_score_vision.py

Test Result

pass

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Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.
• (Optional) Release notes update. If your change is user facing, please update the release notes draft in the Google Doc.

[mergify]

Documentation preview: https://vllm--33298.org.readthedocs.build/en/33298/

[gemini-code-assist]

Code Review

This pull request fixes an issue with loading the Qwen3-VL-Reranker model by adjusting the weight loading logic for sequence classification models, specifically for Vision Language Models (VLMs). The core change introduces a more specific check (using_vlm_head) to correctly identify where the score layer is located in VLMs.

Additionally, the PR refactors the encode_base64_content_from_url utility function into a new vllm.utils.mm_utils module and updates example scripts and tests to use it. This centralization is a good improvement.

My review focuses on a potential issue in the newly introduced utility function. I've suggested a change to make it more robust by dynamically handling image content types and using appropriate headers for GET requests. The rest of the changes, including the main bugfix and the addition of tests, look solid.

[mergify]

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[mergify]

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[mergify]

Hi @noooop, the pre-commit checks have failed. Please run:

uv pip install pre-commit
pre-commit install
pre-commit run --all-files

Then, commit the changes and push to your branch.

For future commits, pre-commit will run automatically on changed files before each commit.

Tip

Is mypy or markdownlint failing?

mypy and markdownlint are run differently in CI. If the failure is related to either of these checks, please use the following commands to run them locally:

# For mypy (substitute "3.10" with the failing version if needed)
pre-commit run --hook-stage manual mypy-3.10
# For markdownlint
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