fix: prefer registered config over remote code in AutoConfig.from_pretrained by HanFa · Pull Request #45094 · huggingface/transformers

HanFa · 2026-03-29T04:21:29Z

When a config class has been explicitly registered via AutoConfig.register(), it should take precedence over auto_map remote code. Previously, trust_remote_code=True with auto_map.AutoConfig in config.json would always load remote code, ignoring the registration.

This caused issues for downstream libraries (e.g., vLLM) that vendor fixed config classes for models with broken remote code — internal calls from AutoTokenizer/AutoProcessor would bypass the registration and load the broken remote class.

What does this PR do?

Fixes: #45093

Code Agent Policy

The Transformers repo is currently being overwhelmed by a large number of PRs and issue comments written by
code agents. We are currently bottlenecked by our ability to review and respond to them. As a result,
we ask that new users do not submit pure code agent PRs at this time.
You may use code agents in drafting or to help you diagnose issues. We'd also ask autonomous "OpenClaw"-like agents
not to open any PRs or issues for the moment.

PRs that appear to be fully agent-written will probably be closed without review, and we may block users who do this
repeatedly or maliciously.

This is a rapidly-evolving situation that's causing significant shockwaves in the open-source community. As a result,
this policy is likely to be updated regularly in the near future. For more information, please read CONTRIBUTING.md.

I confirm that this is not a pure code agent PR.

Before submitting

This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
Did you read the contributor guideline,
Pull Request section?
Was this discussed/approved via a Github issue or the forum? Please add a link
to it if that's the case.
Did you make sure to update the documentation with your changes? Here are the
documentation guidelines, and
here are tips on formatting docstrings.
Did you write any new necessary tests?

Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
members/contributors who may be interested in your PR.

When a class has been explicitly registered via AutoConfig.register() (or other Auto*.register()), it should take precedence over auto_map remote code. Previously, trust_remote_code=True with auto_map entries in config.json would always load remote code, ignoring the registration. This applies the same fix across all Auto classes: AutoConfig, AutoModel, AutoTokenizer, AutoProcessor, AutoFeatureExtractor, AutoImageProcessor, AutoVideoProcessor. This caused issues for downstream libraries (e.g., vLLM) that vendor fixed classes for models with broken remote code — internal calls from AutoTokenizer/AutoProcessor would bypass the registration and load the broken remote class. Fixes: huggingface#45093 Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

hmellor · 2026-03-31T10:38:02Z

Closing as I believe it is expected behaviour that trust_remote_code=True will force load the remote code, even if local code exists.

hmellor · 2026-03-31T10:42:57Z

Having clarified, my understanding of the intended behaviour of trust_remote_code was incorrect.

If there is local code present, Transformers should use it in preference to any remote code.

hmellor

I like this change but will wait for an additional stamp from @ArthurZucker to confirm that this is desired behaviour

…g to transformers) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

hmellor · 2026-03-31T12:40:15Z

The expected behaviour is as follows:

If local code exists in Transformers and remote code exists in the checkpoint - do what trust_remote_code says
If local code exists that was registered outside of Transformers (i.e. by vLLM) - ignore trust_remote_code and always use the expicitly registered local code

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

github-actions · 2026-03-31T14:25:51Z

[For maintainers] Suggested jobs to run (before merge)

run-slow: auto

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

HuggingFaceDocBuilderDev · 2026-03-31T14:38:59Z

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

…trained (huggingface#45094) * Prefer registered classes over remote code in Auto*.from_pretrained When a class has been explicitly registered via AutoConfig.register() (or other Auto*.register()), it should take precedence over auto_map remote code. Previously, trust_remote_code=True with auto_map entries in config.json would always load remote code, ignoring the registration. This applies the same fix across all Auto classes: AutoConfig, AutoModel, AutoTokenizer, AutoProcessor, AutoFeatureExtractor, AutoImageProcessor, AutoVideoProcessor. This caused issues for downstream libraries (e.g., vLLM) that vendor fixed classes for models with broken remote code — internal calls from AutoTokenizer/AutoProcessor would bypass the registration and load the broken remote class. Fixes: huggingface#45093 Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com> * Only ignore remote code if local code is explicit (i.e. doesn't belong to transformers) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> * update tests Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> * `make style` Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> * fix tokenizer test Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> * Fix tests Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> * Fix explicit registration detection Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> * make style Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> --------- Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com> Co-authored-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

HanFa force-pushed the fix/autoconfig-register-precedence branch from 25ef1a9 to 400e4bb Compare March 29, 2026 04:33

HanFa marked this pull request as ready for review March 29, 2026 04:40

github-actions bot requested review from ArthurZucker and ydshieh March 29, 2026 04:40

HanFa force-pushed the fix/autoconfig-register-precedence branch 2 times, most recently from 6187543 to 06bcb31 Compare March 29, 2026 05:10

HanFa force-pushed the fix/autoconfig-register-precedence branch from 06bcb31 to 37100cc Compare March 29, 2026 05:26

HanFa mentioned this pull request Mar 29, 2026

[Transformers v5] HCXVisionForCausalLM vllm-project/vllm#38387

Open

Rocketknight1 mentioned this pull request Mar 30, 2026

AutoConfig.register() ignored when trust_remote_code=True and auto_map is present #45093

Closed

hmellor closed this Mar 31, 2026

hmellor reopened this Mar 31, 2026

hmellor approved these changes Mar 31, 2026

View reviewed changes

hmellor added 3 commits March 31, 2026 14:21

Only ignore remote code if local code is explicit (i.e. doesn't belon…

e22d018

…g to transformers) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

update tests

fb7ee5d

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

make style

ab6e711

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

hmellor enabled auto-merge March 31, 2026 12:40

hmellor added 4 commits March 31, 2026 14:07

Merge branch 'main' into fix/autoconfig-register-precedence

118eb93

fix tokenizer test

f341e9c

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

Fix tests

472e5fc

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

Fix explicit registration detection

be2538c

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

make style

90aba33

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

hmellor added this pull request to the merge queue Mar 31, 2026

Merged via the queue into huggingface:main with commit 81db7d3 Mar 31, 2026
29 checks passed

HanFa mentioned this pull request Mar 31, 2026

[Transformers v5] Vendor HCXVisionConfig for compatibility vllm-project/vllm#38447

Open

hmellor mentioned this pull request Apr 1, 2026

Fix explicit local code resolution for tokenizers and image processors #45169

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

fix: prefer registered config over remote code in AutoConfig.from_pretrained#45094

fix: prefer registered config over remote code in AutoConfig.from_pretrained#45094
hmellor merged 9 commits intohuggingface:mainfrom
HanFa:fix/autoconfig-register-precedence

HanFa commented Mar 29, 2026 •

edited

Loading

Uh oh!

hmellor commented Mar 31, 2026

Uh oh!

hmellor commented Mar 31, 2026

Uh oh!

hmellor left a comment

Uh oh!

hmellor commented Mar 31, 2026 •

edited

Loading

Uh oh!

github-actions bot commented Mar 31, 2026

Uh oh!

HuggingFaceDocBuilderDev commented Mar 31, 2026

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Conversation

HanFa commented Mar 29, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

What does this PR do?

Code Agent Policy

Before submitting

Who can review?

Uh oh!

hmellor commented Mar 31, 2026

Uh oh!

hmellor commented Mar 31, 2026

Uh oh!

hmellor left a comment

Choose a reason for hiding this comment

Uh oh!

hmellor commented Mar 31, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

github-actions bot commented Mar 31, 2026

Uh oh!

HuggingFaceDocBuilderDev commented Mar 31, 2026

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

HanFa commented Mar 29, 2026 •

edited

Loading

hmellor commented Mar 31, 2026 •

edited

Loading