fix: synthesize OpenAI tool calls from json and python fallback

app/http/tool_bridge.py

@@ -161,6 +161,27 @@ def _json_object_from_text(text: str) -> dict[str, Any] | None:
     return parsed if isinstance(parsed, dict) else None
 
 
+def _json_tool_candidate_from_text(text: str) -> dict[str, Any] | None:
+    raw = text.strip()
+    if not raw:
+        return None
+    if raw.startswith("```") and raw.endswith("```"):
+        raw = raw[3:-3].strip()
+        if raw.lower().startswith("json"):
+            raw = raw[4:].strip()
+    try:
+        parsed = json.loads(raw)
+    except Exception:
+        return None
+    if isinstance(parsed, dict):
+        return parsed
+    if isinstance(parsed, list) and parsed:
+        first = parsed[0]
+        if isinstance(first, dict):
+            return first
+    return None
+
+
 def _tool_code_single_arg_name(
     tools: list[dict[str, Any]] | None, forced_tool_name: str
 ) -> str | None:
@@ -199,11 +220,15 @@ def _tool_code_object_from_text(
     single_arg_name: str | None = None,
 ) -> dict[str, Any] | None:
     raw = text.strip()
-    if not raw.startswith("```tool_code") or not raw.endswith("```"):
+    if not raw.startswith("```") or not raw.endswith("```"):
         return None
     lines = raw.splitlines()
     if len(lines) < 2:
         return None
+    fence = lines[0].strip().lower()
+    language = fence[3:].strip()
+    if language and language not in {"tool_code", "python", "py"}:
+        return None
     body = "\n".join(lines[1:-1]).strip()
     try:
         parsed = ast.parse(body, mode="eval")
@@ -239,7 +264,7 @@ def _forced_tool_event_from_text(
     *,
     single_arg_name: str | None = None,
 ) -> dict[str, Any] | None:
-    parsed = _json_object_from_text(text)
+    parsed = _json_tool_candidate_from_text(text)
     if parsed is None:
         parsed = _tool_code_object_from_text(
             text, forced_tool_name, single_arg_name=single_arg_name