feat(licensing): add default-deny engine and model licensing audit

.github/workflows/ci.yml

@@ -19,7 +19,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.13"
-      - run: make check-protocol check-conformance
+      - run: make check-protocol check-conformance check-licensing
 
   dart-and-flutter:
     runs-on: ubuntu-latest

CONTRIBUTING.md

@@ -73,6 +73,13 @@ Keep product commands and billing policy outside the runtime. Provider-specific
 dependencies belong behind adapters, with their licenses and model terms called
 out in the pull request.
 
+A change that adds or bumps an engine, native library, model, voice, tokenizer,
+phonemizer, or test fixture follows the update procedure in
+[licensing/README.md](licensing/README.md). Include the `licensing/manifest.json`
+change and any legal review reference. Never rely on an SDK repository's license
+alone for the artifacts it downloads. A pull request that adds a downloader or a
+packaging path also adds its licensing cross-check in the same pull request.
+
 ## Connector pull requests
 
 A connector contribution should document:

Makefile

@@ -1,8 +1,8 @@
 PROTO_FILES := $(shell find spec/proto -name '*.proto' -type f | sort)
 
-.PHONY: check check-protocol check-conformance check-dart check-flutter check-flutter-plugin check-typescript check-python check-rust
+.PHONY: check check-protocol check-conformance check-licensing check-dart check-flutter check-flutter-plugin check-typescript check-python check-rust
 
-check: check-protocol check-conformance check-dart check-flutter check-flutter-plugin check-typescript check-python check-rust
+check: check-protocol check-conformance check-licensing check-dart check-flutter check-flutter-plugin check-typescript check-python check-rust
 
 check-protocol:
 	@descriptor="$$(mktemp)"; \
@@ -12,6 +12,10 @@ check-protocol:
 check-conformance:
 	python3 tool/check_conformance.py
 
+check-licensing:
+	python3 tool/check_licensing.py
+	python3 -m unittest discover -s tool -p 'test_check_licensing.py' -v
+
 check-dart:
 	cd sdks/dart/murmur_protocol && dart pub get && dart format --output=none --set-exit-if-changed . && dart analyze && dart test
 

THIRD_PARTY_NOTICES.md

@@ -89,3 +89,11 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
 ```
+
+## Engine dependencies and model artifacts
+
+Murmur does not currently distribute any native engine dependency, model
+weight, voice, tokenizer, or phonemizer. The inventory, terms, and review state
+live in [licensing/manifest.json](licensing/manifest.json) and
+[licensing/README.md](licensing/README.md). An artifact's full notice is added
+here before it may be packaged; `make check-licensing` enforces this.

docs/voice-runtime.md

@@ -181,8 +181,12 @@ atomic pack manager instead of making each screen infer readiness.
   preparation
 - unsupported components are explicit rather than reported as ready
 
-Individual engine adapters remain responsible for their upstream licenses,
-model terms, supported platforms, and redistribution rules.
+Packs resolve only entries approved in [licensing/](../licensing/README.md),
+verify each file's hash and size before activation, and present terms as each
+entry's `terms.download.presentation` requires before the first network
+request. An engine adapter's license never stands in for the terms of the
+models, voices, tokenizers, or phonemizers it loads, and each adapter still
+documents its supported platforms.
 
 ## Speech feedback and interruption
 
@@ -226,8 +230,8 @@ regressing.
 - subscription, trial, entitlement, and usage-metering policy
 - private services, endpoints, analytics, and account identifiers
 - host UI components, IPC names, and application state
-- native engines or model assets whose licenses and redistribution terms have
-  not been reviewed for Murmur
+- native engines or model assets that are not approved in
+  [licensing/manifest.json](../licensing/manifest.json)
 - constants tuned to one product without a public configuration and test basis
 
 Murmur can define adapters for these capabilities without making any one