feat: handle gemini tool call tags

.hive/browser-logs/browser-2026-04-04.jsonl

@@ -6,3 +6,4 @@
 {"type": "connection", "event": "disconnect", "ts": "2026-04-04T01:15:12.826042+00:00", "profile": "default"}
 {"type": "connection", "event": "connect", "ts": "2026-04-04T01:15:30.842533+00:00", "profile": "default"}
 {"type": "connection", "event": "hello", "details": {"version": "1.0"}, "ts": "2026-04-04T01:15:30.845025+00:00", "profile": "default"}
+{"type": "tool_call", "tool": "browser_stop", "params": {"profile": "gcu-browser-worker:3"}, "result": {"ok": true, "status": "not_running", "profile": "gcu-browser-worker:3"}, "ok": true, "duration_ms": 0.01, "ts": "2026-04-04T01:29:04.294954+00:00", "profile": "default"}

core/framework/llm/litellm.py

@@ -458,6 +458,57 @@ def _is_stream_transient_error(exc: BaseException) -> bool:
     return isinstance(exc, transient_types)
 
 
+def _extract_text_tool_calls(
+    text: str,
+) -> tuple[list["ToolCallEvent"], str]:
+    """Extract hallucinated tool calls from ``<tool_code>`` blocks in LLM text.
+
+    Some models (notably Gemini) emit tool invocations as text instead of using
+    the structured function-calling API.  This function parses those blocks and
+    returns ``(tool_call_events, cleaned_text)`` where *cleaned_text* has the
+    ``<tool_code>`` blocks removed.
+
+    Expected format::
+
+        <tool_code>
+        {
+          "tool_name": { ...args }
+        }
+        </tool_code>
+    """
+    from framework.llm.stream_events import ToolCallEvent
+
+    pattern = re.compile(r"<tool_code>\s*(.*?)\s*</tool_code>", re.DOTALL)
+    events: list[ToolCallEvent] = []
+    cleaned = text
+
+    for match in pattern.finditer(text):
+        raw = match.group(1).strip()
+        try:
+            payload = json.loads(raw)
+        except json.JSONDecodeError:
+            logger.warning("[_extract_text_tool_calls] failed to parse JSON: %s", raw[:200])
+            continue
+
+        if not isinstance(payload, dict):
+            continue
+
+        for tool_name, tool_args in payload.items():
+            call_id = f"synth_{hashlib.md5(f'{tool_name}:{json.dumps(tool_args, sort_keys=True)}'.encode()).hexdigest()[:12]}"
+            events.append(
+                ToolCallEvent(
+                    tool_use_id=call_id,
+                    tool_name=tool_name,
+                    tool_input=tool_args if isinstance(tool_args, dict) else {},
+                )
+            )
+
+    if events:
+        cleaned = pattern.sub("", text).strip()
+
+    return events, cleaned
+
+
 class LiteLLMProvider(LLMProvider):
     """
     LiteLLM-based LLM provider for multi-provider support.
@@ -1918,6 +1969,35 @@ class LiteLLMProvider(LLMProvider):
                         f"(last_role={last_role}). Returning empty result."
                     )
 
+                # Gemini sometimes outputs tool calls as text in
+                # <tool_code>{"name": {...args}}</tool_code> blocks
+                # instead of using the function-calling API.  Extract
+                # these as real ToolCallEvents and strip them from the
+                # text so the rest of the system treats them normally.
+                if accumulated_text and "<tool_code>" in accumulated_text:
+                    extracted, cleaned = _extract_text_tool_calls(accumulated_text)
+                    if extracted:
+                        logger.info(
+                            "[stream] extracted %d hallucinated tool call(s) from text",
+                            len(extracted),
+                        )
+                        accumulated_text = cleaned
+                        # Emit a corrected TextDeltaEvent so the caller's
+                        # accumulated_text is overwritten with the cleaned text.
+                        yield TextDeltaEvent(content="", snapshot=cleaned)
+                        # Insert synthetic ToolCallEvents before FinishEvent.
+                        finish_idx = next(
+                            (i for i, ev in enumerate(tail_events) if isinstance(ev, FinishEvent)),
+                            len(tail_events),
+                        )
+                        for tc_ev in reversed(extracted):
+                            tail_events.insert(finish_idx, tc_ev)
+                        # Update TextEndEvent if present.
+                        for _i, _ev in enumerate(tail_events):
+                            if isinstance(_ev, TextEndEvent):
+                                tail_events[_i] = TextEndEvent(full_text=cleaned)
+                                break
+
                 # Success (or empty after exhausted retries) — flush events.
                 for event in tail_events:
                     yield event