diff --git a/.github/workflows/consumer-pin-verification.yml b/.github/workflows/consumer-pin-verification.yml
index 4e7cb24a..b84e5b65 100644
--- a/.github/workflows/consumer-pin-verification.yml
+++ b/.github/workflows/consumer-pin-verification.yml
@@ -14,10 +14,12 @@ on:
         description: Ref for ovk-consumer-fastapi-terraform
         required: true
         default: main
+        type: string
       express_ref:
         description: Ref for ovk-consumer-express-actions
         required: true
         default: main
+        type: string
 
 permissions:
   contents: read
@@ -57,7 +59,7 @@ jobs:
         with:
           python-version: "3.12"
 
-      - name: Assert immutable Action SHA pin (no uses: ./)
+      - name: "Assert immutable Action SHA pin (no uses: ./)"
         env:
           OVK_SHA: ${{ inputs.ovk_candidate_sha }}
         working-directory: consumer
diff --git a/tests/test_workflow_dispatch_contracts.py b/tests/test_workflow_dispatch_contracts.py
new file mode 100644
index 00000000..4f743f43
--- /dev/null
+++ b/tests/test_workflow_dispatch_contracts.py
@@ -0,0 +1,104 @@
+import re
+from collections.abc import Iterator
+from pathlib import Path
+
+import yaml
+
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+WORKFLOW_DIR = REPO_ROOT / ".github" / "workflows"
+ALLOWED_DISPATCH_TYPES = {"boolean", "choice", "environment", "number", "string"}
+FULL_COMMIT_PIN = re.compile(r"^[^@\s]+@[0-9a-fA-F]{40}$")
+
+
+def _load_workflow(path: Path) -> dict:
+    """Load workflow YAML without YAML 1.1 coercion of the `on` key."""
+
+    payload = yaml.load(path.read_text(encoding="utf-8"), Loader=yaml.BaseLoader)
+    assert isinstance(payload, dict), f"workflow must be a mapping: {path}"
+    return payload
+
+
+def _iter_workflow_uses(workflow: dict) -> Iterator[str]:
+    """Yield job- and step-level `uses` references from a parsed workflow."""
+
+    jobs = workflow.get("jobs", {})
+    if not isinstance(jobs, dict):
+        return
+    for job in jobs.values():
+        if not isinstance(job, dict):
+            continue
+        job_uses = job.get("uses")
+        if isinstance(job_uses, str):
+            yield job_uses
+        steps = job.get("steps", [])
+        if not isinstance(steps, list):
+            continue
+        for step in steps:
+            if not isinstance(step, dict):
+                continue
+            step_uses = step.get("uses")
+            if isinstance(step_uses, str):
+                yield step_uses
+
+
+def test_all_workflow_dispatch_inputs_have_explicit_supported_types() -> None:
+    """GitHub rejects workflow_dispatch schemas whose inputs omit `type`."""
+
+    checked = 0
+    for path in sorted(WORKFLOW_DIR.glob("*.y*ml")):
+        workflow = _load_workflow(path)
+        triggers = workflow.get("on")
+        if not isinstance(triggers, dict):
+            continue
+        dispatch = triggers.get("workflow_dispatch")
+        if dispatch is None:
+            continue
+        checked += 1
+        if dispatch == "":
+            continue
+        assert isinstance(dispatch, dict), f"workflow_dispatch must be a mapping or null: {path}"
+        inputs = dispatch.get("inputs", {})
+        if inputs == "":
+            continue
+        assert isinstance(inputs, dict), f"workflow_dispatch.inputs must be a mapping: {path}"
+        for input_name, spec in inputs.items():
+            assert isinstance(spec, dict), f"dispatch input {input_name!r} must be a mapping: {path}"
+            input_type = spec.get("type")
+            assert input_type in ALLOWED_DISPATCH_TYPES, (
+                f"dispatch input {input_name!r} in {path} must declare a supported type; got {input_type!r}"
+            )
+
+    assert checked > 0, "expected at least one workflow_dispatch workflow"
+
+
+def test_external_workflow_actions_use_full_commit_sha_pins() -> None:
+    """External actions/reusable workflows must be pinned to exact 40-hex commits."""
+
+    checked = 0
+    for path in sorted(WORKFLOW_DIR.glob("*.y*ml")):
+        workflow = _load_workflow(path)
+        for uses in _iter_workflow_uses(workflow):
+            if uses.startswith("./") or uses.startswith("docker://"):
+                continue
+            checked += 1
+            assert FULL_COMMIT_PIN.fullmatch(uses), (
+                f"external workflow reference must use an exact 40-hex commit SHA: {path}: {uses!r}"
+            )
+
+    assert checked > 0, "expected at least one external workflow reference"
+
+
+def test_consumer_pin_verification_exposes_typed_release_inputs() -> None:
+    """The release-authority consumer workflow must remain dispatchable by GitHub."""
+
+    path = WORKFLOW_DIR / "consumer-pin-verification.yml"
+    workflow = _load_workflow(path)
+    dispatch = workflow["on"]["workflow_dispatch"]
+    inputs = dispatch["inputs"]
+
+    assert set(inputs) == {"ovk_candidate_sha", "fastapi_ref", "express_ref"}
+    assert all(inputs[name]["type"] == "string" for name in inputs)
+    assert inputs["ovk_candidate_sha"]["required"] == "true"
+    assert inputs["fastapi_ref"]["default"] == "main"
+    assert inputs["express_ref"]["default"] == "main"