fix: drop generic repeated tool-call guard

The global guard changed baseline agent and subagent behavior without
proving a real no-progress loop. Keep this PR focused on the cron
contract hardening and validation fixes.

Made-with: Cursor

tests/agent/test_runner.py

@@ -854,48 +854,6 @@ async def test_runner_blocks_repeated_external_fetches():
     assert "repeated external lookup blocked" in blocked_tool_message["content"]
 
 
-@pytest.mark.asyncio
-async def test_runner_blocks_repeated_identical_tool_calls():
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
-
-    provider = MagicMock()
-    captured_final_call: list[dict] = []
-    call_count = {"n": 0}
-
-    async def chat_with_retry(*, messages, **kwargs):
-        call_count["n"] += 1
-        if call_count["n"] <= 3:
-            return LLMResponse(
-                content="working",
-                tool_calls=[ToolCallRequest(id=f"call_{call_count['n']}", name="read_file", arguments={"path": "memory/history.jsonl", "limit": 50, "offset": 1})],
-                usage={},
-            )
-        captured_final_call[:] = messages
-        return LLMResponse(content="done", tool_calls=[], usage={})
-
-    provider.chat_with_retry = chat_with_retry
-    tools = MagicMock()
-    tools.get_definitions.return_value = []
-    tools.execute = AsyncMock(return_value="file content")
-
-    runner = AgentRunner(provider)
-    result = await runner.run(AgentRunSpec(
-        initial_messages=[{"role": "user", "content": "what happened recently?"}],
-        tools=tools,
-        model="test-model",
-        max_iterations=4,
-        max_tool_result_chars=_MAX_TOOL_RESULT_CHARS,
-    ))
-
-    assert result.final_content == "done"
-    assert tools.execute.await_count == 2
-    blocked_tool_message = [
-        msg for msg in captured_final_call
-        if msg.get("role") == "tool" and msg.get("tool_call_id") == "call_3"
-    ][0]
-    assert "repeated identical call to 'read_file' blocked" in blocked_tool_message["content"]
-
-
 @pytest.mark.asyncio
 async def test_loop_max_iterations_message_stays_stable(tmp_path):
     loop = _make_loop(tmp_path)

tests/utils/test_runtime.py

@@ -1,20 +0,0 @@
-from nanobot.utils.runtime import repeated_tool_call_error, tool_call_signature
-
-
-def test_tool_call_signature_sorts_arguments_stably() -> None:
-    first = tool_call_signature("read_file", {"offset": 1, "path": "memory/history.jsonl"})
-    second = tool_call_signature("read_file", {"path": "memory/history.jsonl", "offset": 1})
-
-    assert first == second
-
-
-def test_repeated_tool_call_error_blocks_after_two_attempts() -> None:
-    seen: dict[str, int] = {}
-
-    assert repeated_tool_call_error("read_file", {"path": "a.txt"}, seen) is None
-    assert repeated_tool_call_error("read_file", {"path": "a.txt"}, seen) is None
-
-    error = repeated_tool_call_error("read_file", {"path": "a.txt"}, seen)
-
-    assert error is not None
-    assert "repeated identical call to 'read_file' blocked after 2 attempts" in error