Merge remote-tracking branch 'origin/main' into pr-1488

nanobot/agent/tools/base.py

@@ -54,6 +54,8 @@ class Tool(ABC):
 
     def validate_params(self, params: dict[str, Any]) -> list[str]:
         """Validate tool parameters against JSON schema. Returns error list (empty if valid)."""
+        if not isinstance(params, dict):
+            return [f"parameters must be an object, got {type(params).__name__}"]
         schema = self.parameters or {}
         if schema.get("type", "object") != "object":
             raise ValueError(f"Schema must be object type, got {schema.get('type')!r}")

nanobot/agent/tools/cron.py

@@ -122,7 +122,10 @@ class CronTool(Tool):
         elif at:
             from datetime import datetime
 
-            dt = datetime.fromisoformat(at)
+            try:
+                dt = datetime.fromisoformat(at)
+            except ValueError:
+                return f"Error: invalid ISO datetime format '{at}'. Expected format: YYYY-MM-DDTHH:MM:SS"
             at_ms = int(dt.timestamp() * 1000)
             schedule = CronSchedule(kind="at", at_ms=at_ms)
             delete_after = True

nanobot/agent/tools/filesystem.py

@@ -26,6 +26,8 @@ def _resolve_path(
 class ReadFileTool(Tool):
     """Tool to read file contents."""
 
+    _MAX_CHARS = 128_000  # ~128 KB — prevents OOM from reading huge files into LLM context
+
     def __init__(self, workspace: Path | None = None, allowed_dir: Path | None = None):
         self._workspace = workspace
         self._allowed_dir = allowed_dir
@@ -54,7 +56,16 @@ class ReadFileTool(Tool):
             if not file_path.is_file():
                 return f"Error: Not a file: {path}"
 
+            size = file_path.stat().st_size
+            if size > self._MAX_CHARS * 4:  # rough upper bound (UTF-8 chars ≤ 4 bytes)
+                return (
+                    f"Error: File too large ({size:,} bytes). "
+                    f"Use exec tool with head/tail/grep to read portions."
+                )
+
             content = file_path.read_text(encoding="utf-8")
+            if len(content) > self._MAX_CHARS:
+                return content[: self._MAX_CHARS] + f"\n\n... (truncated — file is {len(content):,} chars, limit {self._MAX_CHARS:,})"
             return content
         except PermissionError as e:
             return f"Error: {e}"