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Issue Content

See #34026 as an example implementation

The vast majority of model settings can be set on a model directly, ex

ChatOpenAI("gpt-4.1-mini", temperature=1)

However, there are a few settings like strict (for tool calling) that you must currently set via middleware's model_settings.

We could consider adding a model_settings arg to create_agent, but this creates another redundant way to do the same thing.

Right now everything you might desire is possible via middleware, but it's more verbose certainly.

Package (Required)

• langchain
• langchain-openai
• langchain-anthropic
• langchain-classic
• langchain-core
• langchain-cli
• langchain-model-profiles
• langchain-tests
• langchain-text-splitters
• langchain-chroma
• langchain-deepseek
• langchain-exa
• langchain-fireworks
• langchain-groq
• langchain-huggingface
• langchain-mistralai
• langchain-nomic
• langchain-ollama
• langchain-perplexity
• langchain-prompty
• langchain-qdrant
• langchain-xai
• Other / not sure / general