feat(core): deprecate problematic dict() method

[cbornet]

dict() is a problematic method name as it clashes with the builtin dict used as a type annotation.
This PR replaces it with an asdict method (inspired by dataclasses).
It also fixes a few places where dict must be replaced by builtins.dict until the dict() method is removed.

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Project	Deployment	Preview	Comments	Updated (UTC)
langchain	Ready	Preview	Comment	Sep 9, 2025 9:51am

[codspeed-hq]

Merging this PR will improve performance by 31.76%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚡ 4 improved benchmarks
✅ 9 untouched benchmarks
⏩ 21 skipped benchmarks¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	WallTime	test_import_time[tool]	530.2 ms	479.5 ms	+10.58%
⚡	WallTime	test_async_callbacks_in_sync	23.8 ms	18 ms	+31.76%
⚡	WallTime	test_import_time[Document]	189.2 ms	172 ms	+10.01%
⚡	WallTime	test_import_time[ChatPromptTemplate]	639.3 ms	570.4 ms	+12.08%

---

_{Comparing cbornet:typing-dict (330e108) with master (2ef2388)}

Footnotes

1. 21 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #31685 will not alter performance

_{Comparing cbornet:typing-dict (92e60c5) with wip-v1.0 (188c015)}

Summary

✅ 14 untouched benchmarks

[eyurtsev]

We could merge as part of the 0.4 release. Unclear yet whether this change should be made -- better not to clash with a built in for new code, but for existing code this would be weighed from a cost benefit analysis to end users

[cbornet]

@eyurtsev candidate for 1.0 ?

[Copilot]

Pull Request Overview

This PR deprecates the problematic dict() method that clashes with Python's builtin dict type annotation and replaces it with an asdict() method inspired by dataclasses. The change addresses type annotation conflicts by introducing proper deprecation warnings and updating internal usage.

Key changes:

• Introduces asdict() method as replacement for dict() across base classes
• Adds deprecation decorators to existing dict() methods with migration guidance
• Updates type annotations from dict to typing.Dict where the builtin conflicts with the method name

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 5 comments.

File	Description
libs/core/langchain_core/prompts/base.py	Adds asdict() method, deprecates dict(), updates type annotations and internal usage
libs/core/langchain_core/output_parsers/base.py	Adds asdict() method and deprecates dict() with proper decorator
libs/core/langchain_core/language_models/llms.py	Updates type annotations, adds asdict() method, and replaces internal dict() calls
libs/core/langchain_core/language_models/chat_models.py	Updates type annotations, adds asdict() method, and replaces internal usage

[mdrxy]

@cbornet please review

[cbornet]

@cbornet please review

done.

[cbornet]

Something wrong happened with the change of git branch 😢

[cbornet]

Rebased on master now that v1 was released.

[sydney-runkle]

Hey @cbornet, if you update against master, can help get this across the line

Thanks!

[cbornet]

Hey @cbornet, if you update against master, can help get this across the line

Rebased against latest master.

[cbornet]

@sydney-runkle I rebased again and updated the deprecation version. Can you take a look ?