Studio: don't drop parallel tool calls after an internal no-op (#7157)

studio/backend/tests/test_tool_loop_controller.py

@@ -13,6 +13,7 @@ if _BACKEND_DIR not in sys.path:
 
 from core.inference.tool_loop_controller import (
     ToolLoopController,
+    append_deferred_nudges,
     canonical_tool_call_key,
     coerce_tool_arguments,
     status_for_tool,
@@ -21,6 +22,22 @@ from core.inference.tool_loop_controller import (
 )
 
 
+def test_append_deferred_nudges_merges_deduped_into_one_message():
+    conversation = [{"role": "assistant", "tool_calls": [1]}, {"role": "tool", "content": "r"}]
+    nudges = [
+        {"role": "user", "content": "duplicate"},
+        {"role": "user", "content": "duplicate"},  # dropped: same content
+        {"role": "user", "content": "disabled foo"},
+    ]
+    append_deferred_nudges(conversation, nudges)
+    # One user message, after the results, with distinct contents joined.
+    assert conversation[2:] == [{"role": "user", "content": "duplicate\n\ndisabled foo"}]
+    # Empty is a no-op.
+    before = list(conversation)
+    append_deferred_nudges(conversation, [])
+    assert conversation == before
+
+
 def _tool(name: str) -> dict:
     return {"type": "function", "function": {"name": name}}
 
@@ -111,6 +128,10 @@ def test_successful_duplicate_is_internal_noop_and_keeps_remaining_tools():
     assert not duplicate.should_execute
     assert not duplicate.emit_visible_events
     duplicate_nudge = completion.model_message()["content"]
+    assert duplicate_nudge.startswith(
+        "One earlier request to call tool 'web_search' in this batch was not executed"
+    )
+    assert "previous tool request" not in duplicate_nudge.lower()
     assert "already completed successfully" in duplicate_nudge
     assert "different enabled tool" in duplicate_nudge
     assert completion.model_message()["role"] == "user"
@@ -165,7 +186,12 @@ def test_empty_enabled_tool_list_blocks_all_tool_calls():
     assert decision.action == "disabled"
     assert not decision.emit_visible_events
     assert completion.model_message()["role"] == "user"
-    assert "not enabled" in completion.model_message()["content"]
+    disabled_nudge = completion.model_message()["content"]
+    assert disabled_nudge.startswith(
+        "One earlier request to call tool 'web_search' in this batch was not executed"
+    )
+    assert "previous tool request" not in disabled_nudge.lower()
+    assert "not enabled" in disabled_nudge
     assert controller.force_final_answer
     assert controller.active_tools() == []