Files
nanobot/nanobot/agent/tools/base.py
Kiplangatkorir df8d09f2b6 fix: guard validate_params against non-dict input
When the LLM returns malformed tool arguments (e.g. a list or string
instead of a dict), validate_params would crash with AttributeError
in _validate() when calling val.items(). Now returns a clear
validation error instead of crashing.
2026-03-04 10:53:30 +03:00

107 lines
3.7 KiB
Python

"""Base class for agent tools."""
from abc import ABC, abstractmethod
from typing import Any
class Tool(ABC):
"""
Abstract base class for agent tools.
Tools are capabilities that the agent can use to interact with
the environment, such as reading files, executing commands, etc.
"""
_TYPE_MAP = {
"string": str,
"integer": int,
"number": (int, float),
"boolean": bool,
"array": list,
"object": dict,
}
@property
@abstractmethod
def name(self) -> str:
"""Tool name used in function calls."""
pass
@property
@abstractmethod
def description(self) -> str:
"""Description of what the tool does."""
pass
@property
@abstractmethod
def parameters(self) -> dict[str, Any]:
"""JSON Schema for tool parameters."""
pass
@abstractmethod
async def execute(self, **kwargs: Any) -> str:
"""
Execute the tool with given parameters.
Args:
**kwargs: Tool-specific parameters.
Returns:
String result of the tool execution.
"""
pass
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}")
return self._validate(params, {**schema, "type": "object"}, "")
def _validate(self, val: Any, schema: dict[str, Any], path: str) -> list[str]:
t, label = schema.get("type"), path or "parameter"
if t in self._TYPE_MAP and not isinstance(val, self._TYPE_MAP[t]):
return [f"{label} should be {t}"]
errors = []
if "enum" in schema and val not in schema["enum"]:
errors.append(f"{label} must be one of {schema['enum']}")
if t in ("integer", "number"):
if "minimum" in schema and val < schema["minimum"]:
errors.append(f"{label} must be >= {schema['minimum']}")
if "maximum" in schema and val > schema["maximum"]:
errors.append(f"{label} must be <= {schema['maximum']}")
if t == "string":
if "minLength" in schema and len(val) < schema["minLength"]:
errors.append(f"{label} must be at least {schema['minLength']} chars")
if "maxLength" in schema and len(val) > schema["maxLength"]:
errors.append(f"{label} must be at most {schema['maxLength']} chars")
if t == "object":
props = schema.get("properties", {})
for k in schema.get("required", []):
if k not in val:
errors.append(f"missing required {path + '.' + k if path else k}")
for k, v in val.items():
if k in props:
errors.extend(self._validate(v, props[k], path + "." + k if path else k))
if t == "array" and "items" in schema:
for i, item in enumerate(val):
errors.extend(
self._validate(item, schema["items"], f"{path}[{i}]" if path else f"[{i}]")
)
return errors
def to_schema(self) -> dict[str, Any]:
"""Convert tool to OpenAI function schema format."""
return {
"type": "function",
"function": {
"name": self.name,
"description": self.description,
"parameters": self.parameters,
},
}