diff --git a/AGENTS.md b/AGENTS.md
new file mode 100644
index 0000000..e2bd3f1
--- /dev/null
+++ b/AGENTS.md
@@ -0,0 +1,2 @@
+# Testing Instructions
+You must complete pre-commit checks before finishing the task.
diff --git a/pre_commit.sh b/pre_commit.sh
new file mode 100755
index 0000000..35ba984
--- /dev/null
+++ b/pre_commit.sh
@@ -0,0 +1,8 @@
+#!/bin/bash
+set -e
+echo "Running pre-commit checks..."
+cd zenith
+ruff check tests/test_dispatcher.py
+ruff format tests/test_dispatcher.py
+MYPYPATH=src mypy tests/test_dispatcher.py
+python -m pytest -v tests/test_dispatcher.py
diff --git a/zenith/tests/test_dispatcher.py b/zenith/tests/test_dispatcher.py
new file mode 100644
index 0000000..f28af40
--- /dev/null
+++ b/zenith/tests/test_dispatcher.py
@@ -0,0 +1,123 @@
+from zenith_harness.dispatcher import (
+    MockDispatcher,
+    MockTerminalReviewer,
+    DispatchRequest,
+)
+from zenith_harness.models import (
+    Task,
+    WorkHandoff,
+    ValidateHandoff,
+    TerminalReviewHandoff,
+)
+
+
+def test_mock_dispatcher_dispatch():
+    def responder(request: DispatchRequest):
+        return WorkHandoff(
+            node_id=request.task.id,
+            done=True,
+            report="ok",
+            request_attention=False,
+        )
+
+    dispatcher = MockDispatcher(responder)
+
+    task = Task(id="t1", type="work", body="test body", targets=["assert1"])
+    request = DispatchRequest(project_id="p1", mission_id="m1", task=task, spawn_ts="123")
+
+    result = dispatcher.dispatch(request)
+
+    assert len(dispatcher.calls) == 1
+    assert dispatcher.calls[0] == request
+
+    assert isinstance(result, WorkHandoff)
+    assert result.node_id == "t1"
+    assert result.done is True
+    assert result.report == "ok"
+
+
+def test_mock_dispatcher_dispatch_batch():
+    def responder(request: DispatchRequest):
+        return WorkHandoff(
+            node_id=request.task.id,
+            done=True,
+            report=f"ok {request.task.id}",
+            request_attention=False,
+        )
+
+    dispatcher = MockDispatcher(responder)
+
+    tasks = [
+        Task(id="t1", type="work", body="test body", targets=["assert1"]),
+        Task(id="t2", type="work", body="test body", targets=["assert1"]),
+    ]
+    requests = [
+        DispatchRequest(project_id="p1", mission_id="m1", task=tasks[0], spawn_ts="123"),
+        DispatchRequest(project_id="p1", mission_id="m1", task=tasks[1], spawn_ts="123"),
+    ]
+
+    results = dispatcher.dispatch_batch(requests)
+
+    assert len(dispatcher.calls) == 2
+    # Order might vary
+    call_ids = {c.task.id for c in dispatcher.calls}
+    assert call_ids == {"t1", "t2"}
+
+    assert len(results) == 2
+    result_reports = {r.report for r in results}
+    assert result_reports == {"ok t1", "ok t2"}
+
+
+def test_mock_dispatcher_dispatch_batch_exception_validate():
+    def responder(request: DispatchRequest):
+        raise ValueError("simulated error")
+
+    dispatcher = MockDispatcher(responder)
+
+    task = Task(id="t1", type="validate", body="test body", targets=["assert1"])
+    request = DispatchRequest(project_id="p1", mission_id="m1", task=task, spawn_ts="123")
+
+    results = dispatcher.dispatch_batch([request])
+
+    assert len(results) == 1
+    result = results[0]
+
+    assert isinstance(result, ValidateHandoff)
+    assert result.node_id == "t1"
+    assert result.done is False
+    assert result.passed is False
+    assert "Dispatcher crashed" in result.report
+    assert "simulated error" in result.report
+
+
+def test_mock_dispatcher_dispatch_batch_exception_work():
+    def responder(request: DispatchRequest):
+        raise ValueError("simulated error")
+
+    dispatcher = MockDispatcher(responder)
+
+    task = Task(id="t1", type="work", body="test body", targets=["assert1"])
+    request = DispatchRequest(project_id="p1", mission_id="m1", task=task, spawn_ts="123")
+
+    results = dispatcher.dispatch_batch([request])
+
+    assert len(results) == 1
+    result = results[0]
+
+    assert isinstance(result, WorkHandoff)
+    assert result.node_id == "t1"
+    assert result.done is False
+    assert result.request_attention is False
+    assert "Dispatcher crashed" in result.report
+    assert "simulated error" in result.report
+
+
+def test_mock_terminal_reviewer():
+    review_handoff = TerminalReviewHandoff(done=True, report="looks good")
+    reviewer = MockTerminalReviewer(review_handoff)
+
+    result = reviewer.review(project_id="p1", mission_id="m1", spawn_ts="123")
+
+    assert result == review_handoff
+    assert len(reviewer.calls) == 1
+    assert reviewer.calls[0] == ("p1", "m1", "123")