The server demonstrates good overall definition quality with clear naming conventions, comprehensive parameter schemas, and detailed descriptions. All five tools follow the verb_noun pattern (hex_list, hex_get, hex_run, hex_cancel) and include Pydantic models with full type annotations. Descriptions range from 100-200 chars, meeting best practices. However, output schemas are not explicitly documented, and error handling lacks actionable recovery guidance. The code shows strong foundational work but misses some production refinements.

• Add explicit return type documentation to each tool. E.g., '@mcp_server.tool()' decorator should include a docstring defining the response schema with field names, types, and meanings. Example: 'Returns: {projects: [{id, name, status, created_at, owner_email, ...}], total_count, has_more}'.
• Enhance error handling to categorize failures. Replace bare HexAPIError catches with structured error responses that specify: (1) error category (retryable, user-fixable, fatal), (2) the invalid value if applicable, (3) recovery guidance. E.g., 'Invalid project_id "abc": not found. Available projects: [...]'.
• Add min/max validation to numeric parameters. In ListProjectsParams, change limit Field to: Field(default=25, ge=1, le=100, description='Number of results per page (1-100)').
• Document input_params schema for hex_run_project. Add a docstring or example showing valid parameter structure, or accept a TypedDict/Pydantic subclass instead of generic dict.
• Include pagination metadata in list responses. Modify hex_list_projects to return {projects: [...], total_count: int, has_more: bool, next_cursor?: str} so agents can paginate without guessing.
• Implement optional dry-run validation for destructive tools. For hex_cancel_run, if dry_run=true, return a preview of what would be canceled without actually canceling. Document this in the description.
• Add access control logging. Log who (which agent) called which tool with which parameters and when. This enables audit trails and debugging without exposing secrets in logs.