| """Tool abstraction, argument validation and dispatch.""" |
|
|
| from __future__ import annotations |
|
|
| import abc |
| import time |
| from dataclasses import dataclass, field |
| from pathlib import Path |
| from typing import Any |
|
|
| from ycode.errors import PathSecurityError, PermissionDenied, ToolError |
| from ycode.security.permissions import PermissionManager |
|
|
|
|
| @dataclass |
| class ToolResult: |
| """Outcome of a tool call. |
| |
| ``content`` goes back to the model; ``summary`` is the one-line status shown |
| to the user; ``display`` holds optional extra UI data (e.g. a diff). |
| """ |
|
|
| content: str |
| is_error: bool = False |
| summary: str = "" |
| display: dict[str, Any] = field(default_factory=dict) |
| duration: float = 0.0 |
|
|
| @classmethod |
| def error(cls, message: str, summary: str | None = None) -> "ToolResult": |
| return cls(content=f"Error: {message}", is_error=True, summary=summary or message) |
|
|
|
|
| @dataclass |
| class ToolContext: |
| workspace: Path |
| permissions: PermissionManager |
| ignore_dirs: tuple[str, ...] |
| command_timeout: int = 120 |
| max_output_chars: int = 30000 |
| |
| changed_files: set[str] = field(default_factory=set) |
| |
| commands_run: list[tuple[str, int | None]] = field(default_factory=list) |
|
|
|
|
| class Tool(abc.ABC): |
| name: str |
| description: str |
| parameters: dict[str, Any] |
|
|
| @abc.abstractmethod |
| def run(self, args: dict[str, Any], ctx: ToolContext) -> ToolResult: ... |
|
|
| def describe(self, args: dict[str, Any]) -> str: |
| """Short human-readable description of a call, e.g. 'Reading src/a.py'.""" |
| return self.name |
|
|
| def spec(self) -> dict[str, Any]: |
| return {"name": self.name, "description": self.description, "parameters": self.parameters} |
|
|
|
|
| |
|
|
| _JSON_TYPES: dict[str, tuple[type, ...]] = { |
| "string": (str,), |
| "integer": (int,), |
| "number": (int, float), |
| "boolean": (bool,), |
| "array": (list,), |
| "object": (dict,), |
| } |
|
|
|
|
| def validate_args(schema: dict[str, Any], args: Any) -> str | None: |
| """Minimal JSON-schema check for tool inputs. Returns an error or None.""" |
| if not isinstance(args, dict): |
| return f"arguments must be a JSON object, got {type(args).__name__}" |
| props: dict[str, Any] = schema.get("properties", {}) |
| for name in schema.get("required", []): |
| if name not in args: |
| return f"missing required argument '{name}'" |
| for name, value in args.items(): |
| prop = props.get(name) |
| if prop is None: |
| if schema.get("additionalProperties") is False: |
| return f"unexpected argument '{name}'" |
| continue |
| expected = prop.get("type") |
| if expected and value is not None: |
| types = _JSON_TYPES.get(expected, (object,)) |
| if isinstance(value, bool) and expected in ("integer", "number"): |
| return f"argument '{name}' must be {expected}" |
| if not isinstance(value, types): |
| return f"argument '{name}' must be {expected}, got {type(value).__name__}" |
| if "enum" in prop and value not in prop["enum"]: |
| return f"argument '{name}' must be one of {prop['enum']}" |
| return None |
|
|
|
|
| class ToolRegistry: |
| def __init__(self, tools: list[Tool] | None = None) -> None: |
| self._tools: dict[str, Tool] = {} |
| for tool in tools or []: |
| self.register(tool) |
|
|
| def register(self, tool: Tool) -> None: |
| if tool.name in self._tools: |
| raise ValueError(f"duplicate tool name {tool.name!r}") |
| self._tools[tool.name] = tool |
|
|
| def get(self, name: str) -> Tool | None: |
| return self._tools.get(name) |
|
|
| def names(self) -> list[str]: |
| return list(self._tools) |
|
|
| def specs(self) -> list[dict[str, Any]]: |
| return [tool.spec() for tool in self._tools.values()] |
|
|
| def describe(self, name: str, args: Any) -> str: |
| tool = self._tools.get(name) |
| if tool is None or not isinstance(args, dict): |
| return name |
| try: |
| return tool.describe(args) |
| except Exception: |
| return name |
|
|
| def dispatch(self, name: str, args: Any, ctx: ToolContext) -> ToolResult: |
| """Validate and execute a tool call. Never raises for tool-level errors.""" |
| start = time.monotonic() |
| tool = self._tools.get(name) |
| if tool is None: |
| result = ToolResult.error( |
| f"unknown tool '{name}'. Available tools: {', '.join(self._tools)}", |
| summary=f"Unknown tool {name}", |
| ) |
| else: |
| problem = validate_args(tool.parameters, args) |
| if problem: |
| result = ToolResult.error(f"invalid arguments for {name}: {problem}", summary="Invalid tool call") |
| else: |
| try: |
| result = tool.run(args, ctx) |
| except PermissionDenied as exc: |
| result = ToolResult( |
| content=f"Permission denied: {exc}. Do not retry the same action; " |
| "choose a different approach or ask the user.", |
| is_error=True, |
| summary=str(exc), |
| ) |
| except PathSecurityError as exc: |
| result = ToolResult.error(str(exc), summary="Blocked path") |
| except ToolError as exc: |
| result = ToolResult.error(str(exc)) |
| except KeyboardInterrupt: |
| raise |
| except Exception as exc: |
| result = ToolResult.error(f"{type(exc).__name__}: {exc}", summary=f"{name} failed") |
| result.duration = time.monotonic() - start |
| return result |
|
|
|
|
| def truncate_middle(text: str, limit: int) -> str: |
| """Keep the head and tail of long output; errors are usually at the end.""" |
| if len(text) <= limit: |
| return text |
| head = limit // 3 |
| tail = limit - head |
| omitted = len(text) - head - tail |
| return f"{text[:head]}\n\n... [{omitted} characters omitted] ...\n\n{text[-tail:]}" |
|
|
