ai-station/.venv/lib/python3.12/site-packages/mcp/shared/tool_name_validation.py

130 lines
4.4 KiB
Python

"""Tool name validation utilities according to SEP-986.
Tool names SHOULD be between 1 and 128 characters in length (inclusive).
Tool names are case-sensitive.
Allowed characters: uppercase and lowercase ASCII letters (A-Z, a-z),
digits (0-9), underscore (_), dash (-), and dot (.).
Tool names SHOULD NOT contain spaces, commas, or other special characters.
See: https://modelcontextprotocol.io/specification/2025-11-25/server/tools#tool-names
"""
from __future__ import annotations
import logging
import re
from dataclasses import dataclass, field
logger = logging.getLogger(__name__)
# Regular expression for valid tool names according to SEP-986 specification
TOOL_NAME_REGEX = re.compile(r"^[A-Za-z0-9._-]{1,128}$")
# SEP reference URL for warning messages
SEP_986_URL = "https://modelcontextprotocol.io/specification/2025-11-25/server/tools#tool-names"
@dataclass
class ToolNameValidationResult:
"""Result of tool name validation.
Attributes:
is_valid: Whether the tool name conforms to SEP-986 requirements.
warnings: List of warning messages for non-conforming aspects.
"""
is_valid: bool
warnings: list[str] = field(default_factory=lambda: [])
def validate_tool_name(name: str) -> ToolNameValidationResult:
"""Validate a tool name according to the SEP-986 specification.
Args:
name: The tool name to validate.
Returns:
ToolNameValidationResult containing validation status and any warnings.
"""
warnings: list[str] = []
# Check for empty name
if not name:
return ToolNameValidationResult(
is_valid=False,
warnings=["Tool name cannot be empty"],
)
# Check length
if len(name) > 128:
return ToolNameValidationResult(
is_valid=False,
warnings=[f"Tool name exceeds maximum length of 128 characters (current: {len(name)})"],
)
# Check for problematic patterns (warnings, not validation failures)
if " " in name:
warnings.append("Tool name contains spaces, which may cause parsing issues")
if "," in name:
warnings.append("Tool name contains commas, which may cause parsing issues")
# Check for potentially confusing leading/trailing characters
if name.startswith("-") or name.endswith("-"):
warnings.append("Tool name starts or ends with a dash, which may cause parsing issues in some contexts")
if name.startswith(".") or name.endswith("."):
warnings.append("Tool name starts or ends with a dot, which may cause parsing issues in some contexts")
# Check for invalid characters
if not TOOL_NAME_REGEX.match(name):
# Find all invalid characters (unique, preserving order)
invalid_chars: list[str] = []
seen: set[str] = set()
for char in name:
if not re.match(r"[A-Za-z0-9._-]", char) and char not in seen:
invalid_chars.append(char)
seen.add(char)
warnings.append(f"Tool name contains invalid characters: {', '.join(repr(c) for c in invalid_chars)}")
warnings.append("Allowed characters are: A-Z, a-z, 0-9, underscore (_), dash (-), and dot (.)")
return ToolNameValidationResult(is_valid=False, warnings=warnings)
return ToolNameValidationResult(is_valid=True, warnings=warnings)
def issue_tool_name_warning(name: str, warnings: list[str]) -> None:
"""Log warnings for non-conforming tool names.
Args:
name: The tool name that triggered the warnings.
warnings: List of warning messages to log.
"""
if not warnings:
return
logger.warning(f'Tool name validation warning for "{name}":')
for warning in warnings:
logger.warning(f" - {warning}")
logger.warning("Tool registration will proceed, but this may cause compatibility issues.")
logger.warning("Consider updating the tool name to conform to the MCP tool naming standard.")
logger.warning(f"See SEP-986 ({SEP_986_URL}) for more details.")
def validate_and_warn_tool_name(name: str) -> bool:
"""Validate a tool name and issue warnings for non-conforming names.
This is the primary entry point for tool name validation. It validates
the name and logs any warnings via the logging module.
Args:
name: The tool name to validate.
Returns:
True if the name is valid, False otherwise.
"""
result = validate_tool_name(name)
issue_tool_name_warning(name, result.warnings)
return result.is_valid