PyGithub MCP Server

Instructions

Implementation Reference

• src/pygithub_mcp_server/tools/issues/tools.py:239-274 (handler)

  MCP tool handler: validates parameters with ListIssueCommentsParams, delegates to operations layer, formats result as MCP content or error.
  @tool() def list_issue_comments(params: ListIssueCommentsParams) -> dict: """List comments on an issue. Args: params: Parameters for listing comments including: - owner: Repository owner (user or organization) - repo: Repository name - issue_number: Issue number - since: Filter by date (optional) - page: Page number (optional) - per_page: Results per page (optional) Returns: List of comments from GitHub API """ try: logger.debug(f"list_issue_comments called with params: {params}") # Pass the Pydantic model directly to the operation result = issues.list_issue_comments(params) logger.debug(f"Got result: {result}") return {"content": [{"type": "text", "text": json.dumps(result, indent=2)}]} except GitHubError as e: logger.error(f"GitHub error: {e}") return { "content": [{"type": "error", "text": format_github_error(e)}], "is_error": True } except Exception as e: logger.error(f"Unexpected error: {e}") logger.error(traceback.format_exc()) error_msg = str(e) if str(e) else "An unexpected error occurred" return { "content": [{"type": "error", "text": f"Internal server error: {error_msg}"}], "is_error": True }
• src/pygithub_mcp_server/schemas/issues.py:228-299 (schema)

  Pydantic schema model ListIssueCommentsParams for input validation, inherits from RepositoryRef, includes validators for pagination and datetime.
  class ListIssueCommentsParams(RepositoryRef): """Parameters for listing comments on an issue.""" model_config = ConfigDict(strict=True) issue_number: int = Field(..., description="Issue number to list comments for") since: Optional[datetime] = Field( None, description="Filter by date (ISO 8601 format with timezone: YYYY-MM-DDThh:mm:ssZ)" ) page: Optional[int] = Field( None, description="Page number for pagination (1-based)" ) per_page: Optional[int] = Field( None, description="Results per page (max 100)" ) @field_validator('page') @classmethod def validate_page(cls, v): """Validate that page is a positive integer.""" if v is not None and v < 1: raise ValueError("Page number must be a positive integer") return v @field_validator('per_page') @classmethod def validate_per_page(cls, v): """Validate that per_page is a positive integer <= 100.""" if v is not None: if v < 1: raise ValueError("Results per page must be a positive integer") if v > 100: raise ValueError("Results per page cannot exceed 100") return v @field_validator('since', mode='before') @classmethod def validate_since(cls, v): """Convert string dates to datetime objects. Accepts: - ISO 8601 format strings with timezone (e.g., "2020-01-01T00:00:00Z") - ISO 8601 format strings with timezone without colon (e.g., "2020-01-01T12:30:45-0500") - ISO 8601 format strings with short timezone (e.g., "2020-01-01T12:30:45+05") - ISO 8601 format strings with single digit timezone (e.g., "2020-01-01T12:30:45-5") - datetime objects Returns: - datetime object Raises: - ValueError: If the string cannot be converted to a valid datetime object """ if isinstance(v, str): # Basic validation - must have 'T' and some form of timezone indicator if not ('T' in v and ('+' in v or 'Z' in v or '-' in v.split('T')[1])): raise ValueError( f"Invalid ISO format datetime: {v}. " f"Must include date, time with 'T' separator, and timezone." ) try: # Try to convert using our flexible converter return convert_iso_string_to_datetime(v) except ValueError as e: # Only raise if conversion actually fails raise ValueError(f"Invalid ISO format datetime: {v}. {str(e)}") return v
• src/pygithub_mcp_server/tools/issues/tools.py:439-463 (registration)

  Tool registration function that includes list_issue_comments in the list of issue tools passed to register_tools for MCP server.
  def register(mcp: FastMCP) -> None: """Register all issue tools with the MCP server. Args: mcp: The MCP server instance """ from pygithub_mcp_server.tools import register_tools # List of all issue tools to register issue_tools = [ create_issue, list_issues, get_issue, update_issue, add_issue_comment, list_issue_comments, update_issue_comment, delete_issue_comment, add_issue_labels, remove_issue_label, ] register_tools(mcp, issue_tools) logger.debug(f"Registered {len(issue_tools)} issue tools")
• src/pygithub_mcp_server/operations/issues.py:271-308 (helper)

  Core helper function implementing GitHub API interaction via PyGithub: fetches issue comments with pagination and since filter, converts to dicts.
  def list_issue_comments(params: ListIssueCommentsParams) -> List[Dict[str, Any]]: """List comments on an issue. Args: params: Validated parameters for listing comments Returns: List of comments from GitHub API Raises: GitHubError: If the API request fails """ try: client = GitHubClient.get_instance() repository = client.get_repo(f"{params.owner}/{params.repo}") issue = repository.get_issue(params.issue_number) # Build kwargs for get_comments kwargs = {} if params.since is not None: logger.debug(f"Using UTC since parameter: {params.since.isoformat()}") kwargs["since"] = params.since # Get paginated comments with only provided parameters paginated_comments = issue.get_comments(**kwargs) # Use our pagination utility for consistent pagination handling comments = get_paginated_items(paginated_comments, params.page, params.per_page) logger.debug(f"Retrieved {len(comments)} comments") # Convert each comment to our schema converted_comments = [convert_issue_comment(comment) for comment in comments] return converted_comments except GithubException as e: raise GitHubClient.get_instance()._handle_github_exception(e)