[campoy]

#126 made Activity nodes and tasks rebuild class-based contexts by default. That breaks apps upgrading from 0.1.0 in three ways. I checked each by running 0.1.0 and #126 against a local server:

• Code that reads a dataclass or Pydantic context as a dictionary (runtime.context["user_id"]) now fails with TypeError.
• A context whose class isn't declared as a context_schema now fails the Workflow task. Workflows started on 0.1.0 fail the same way when they replay.
• context_schema=dict[str, Any] now fails when the plugin is created.

This adds restore_context_types to LangGraphPlugin. The default stays True. With False:

• Activity nodes and tasks receive the context as decoded by the payload converter, as in 0.1.0.
• Contexts of undeclared classes are allowed.
• Workflows still attach schema IDs for declared classes. Workers with either setting can run side by side, so turning restoration on later is a rolling deploy.

Schemas that aren't classes are now accepted with either setting.

How compatibility holds

• Preserve typed context in LangGraph Activity nodes and tasks #126 didn't change Workflow commands, so 0.1.0 histories replay without patching. New tests replay saved 0.1.0 histories with both settings. With restoration on, an undeclared class still fails replay, and the README says to declare classes before turning it on.
• 0.1.0 workers ignore the new schema ID in the Activity input, and new workers accept input without it.
• A Functional API task scheduled by a 0.1.0 worker has no schema ID, so a worker with restoration on gives it a dictionary. The README's upgrade steps avoid this by upgrading with restoration off first.

Not included: aliases for renamed context classes.

Testing

The 0.1.0 histories were recorded by running this branch's TwoNodesWorkflow with the 0.1.0 plugin source. The worker identity is replaced with recorder.

Locally, from source against a dev server with cached SDK 1.34.0 and LangGraph 1.2.9: all graph context cases, both replay tests, the Functional API context test and the validation tests pass. ruff 0.15.22, mypy 1.18.2, basedpyright 1.34.0, pydocstyle and the conventions check pass. make lint, make test and make build can't run locally because the installed uv is 0.11.21 and the repo needs >=0.12.5, so CI runs the supported matrix.

[campoy]

Move python/langgraph/CONTEXT-RESTORATION-PLAN.md to python/langgraph/docs/CONTEXT-RESTORATION-PLAN.md