Drop dead OpenWireModel; add --frozen to codegen invocations; tighten generated-file pyright suppression

Author: maxisbey

.github/workflows/shared.yml

@@ -33,7 +33,7 @@ jobs:
       - name: Surface types match vendored schema
         run: |
           uv sync --group codegen --frozen
-          uv run --group codegen python scripts/gen_surface_types.py --check
+          uv run --frozen --group codegen python scripts/gen_surface_types.py --check
 
       # TODO(Max): Drop this in v2. Deliberate updates (e.g. the v2 status
       # banner) go through the 'override-readme-freeze' label.

pyproject.toml

@@ -178,7 +178,7 @@ max-complexity = 24 # Default is 10
 
 [tool.ruff.lint.per-file-ignores]
 "__init__.py" = ["F401"]
-# Generated by scripts/gen_surface_types.py: raw datamodel-codegen output.
+# Generated by scripts/gen_surface_types.py: raw datamodel-codegen output (TID251 lifts the repo-wide RootModel ban for these generated validators).
 "src/mcp/types/v*/__init__.py" = ["D212", "E501", "I001", "TID251", "UP007", "UP037"]
 "tests/server/mcpserver/test_func_metadata.py" = ["E501"]
 "tests/shared/test_progress_notifications.py" = ["PLW0603"]

scripts/gen_surface_types.py

@@ -4,7 +4,7 @@
 writes the result to ``src/mcp/types/v<version>/__init__.py`` with only the
 fixes the raw output needs: a small JSON pre-patch for the known
 ``number``-as-``integer`` schema.json defect, a header, and per-version
-epilogue aliases. Run with ``uv run --group codegen python scripts/gen_surface_types.py [--check]``.
+epilogue aliases. Run with ``uv run --frozen --group codegen python scripts/gen_surface_types.py [--check]``.
 """
 
 from __future__ import annotations
@@ -27,6 +27,7 @@
 
 # schema.ts -> schema.json renders TypeScript ``number`` as JSON Schema
 # ``integer`` at these sites; patch the JSON before codegen so floats validate.
+# TODO: drop once modelcontextprotocol/modelcontextprotocol fixes the schema.ts -> schema.json number rendering.
 SCHEMA_PATCHES: dict[str, list[tuple[str, Any, Any]]] = {
     "2025-11-25": [
         ("$defs/NumberSchema/properties/default/type", "integer", "number"),
@@ -93,7 +94,7 @@ def patch_schema(schema: dict[str, Any], patches: list[tuple[str, Any, Any]]) ->
 def run_codegen(schema_path: Path, output_path: Path) -> None:
     """Run datamodel-code-generator (from the ``codegen`` dependency group)."""
     exe = shutil.which("datamodel-codegen")
-    cmd = [exe] if exe else ["uv", "run", "--group", "codegen", "datamodel-codegen"]
+    cmd = [exe] if exe else ["uv", "run", "--frozen", "--group", "codegen", "datamodel-codegen"]
     # fmt: off
     result = subprocess.run(
         [

src/mcp/types/_wire_base.py

@@ -1,19 +1,9 @@
-"""Shared pydantic bases for the `mcp.types.v*` wire-shape packages.
-
-No alias generator is configured: every wire name is an explicit
-`Field(alias=...)` so each surface file shows exactly what goes on the wire.
-"""
+"""Shared pydantic base for the generated ``mcp.types.v*`` wire-shape packages."""
 
 from pydantic import BaseModel, ConfigDict
 
 
 class WireModel(BaseModel):
-    """Base for surface-package models: unknown fields are accepted and dropped."""
-
-    model_config = ConfigDict(populate_by_name=True, extra="ignore")
-
-
-class OpenWireModel(BaseModel):
-    """Base for `_meta` carrier models: unknown fields are retained for round-tripping."""
+    """Base for generated wire models: enables ``populate_by_name``; subclasses set ``extra="allow"`` themselves."""
 
-    model_config = ConfigDict(populate_by_name=True, extra="allow")
+    model_config = ConfigDict(populate_by_name=True)