diff --git a/architecture/build.md b/architecture/build.md
index 63d4e56849..cc94d17eaa 100644
--- a/architecture/build.md
+++ b/architecture/build.md
@@ -133,9 +133,11 @@ do not infer from kube context.
 ## Python Wheel Packaging
 
 The generated protobuf/gRPC stubs under `python/openshell/_proto/` are gitignored
-build outputs of `mise run python:proto`. maturin honors `.gitignore` when
-collecting `python-source` files, so native builds (Linux CI, local
-`pip install .`) would drop them and ship an unimportable wheel. `pyproject.toml`
+build outputs of `mise run python:proto`. The task uses `uv run --frozen` to
+synchronize the current worktree's `.venv` from `uv.lock` before generation.
+maturin honors `.gitignore` when collecting `python-source` files, so native
+builds (Linux CI, local `pip install .`) would drop them and ship an unimportable
+wheel. `pyproject.toml`
 pins them back in with `[tool.maturin].include` globs. The release workflows
 install each Linux wheel in a clean image and import `openshell.sandbox` as a
 smoke check.
diff --git a/tasks/python.toml b/tasks/python.toml
index 3aa9727ebf..e04bf27bb4 100644
--- a/tasks/python.toml
+++ b/tasks/python.toml
@@ -218,11 +218,10 @@ hide = true
 
 ["python:proto"]
 description = "Generate Python protobuf stubs from .proto files"
-env = { UV_NO_SYNC = "1" }
 run = """
 #!/usr/bin/env bash
 set -euo pipefail
-uv run python -m grpc_tools.protoc \
+uv run --frozen python -m grpc_tools.protoc \
   -Iproto \
   --python_out=python/openshell/_proto \
   --pyi_out=python/openshell/_proto \
@@ -233,7 +232,7 @@ uv run python -m grpc_tools.protoc \
   proto/options.proto \
   proto/sandbox.proto
 # Fix absolute imports in generated stubs to use package-relative imports
-uv run python - <<'PY'
+uv run --frozen python - <<'PY'
 from pathlib import Path
 import re