This is the official MCP Python SDK repository, not a deployed MCP server. The three tools examined ('fetch', 'add', 'name_shrimp') are example implementations in separate example directories (simple-tool, fastmcp/desktop.py, fastmcp/complex_inputs.py). Critical issues: (1) Tool definitions are scattered across example files with no central registration visible in the source provided. (2) The 'add' tool has a malformed schema, 'a' and 'b' properties lack a 'required' array at the schema root, making their necessity ambiguous to consumers. (3) The 'name_shrimp' tool's input schema references a 'ShrimpTank model' object without providing its schema definition, violating the pattern:tool-schema requirement. (4) Descriptions are minimal and do not articulate WHEN or WHY to use each tool. (5) No error handling guidance, no output schemas documented, no parameter constraints (enums, ranges) defined. (6) Tool definitions appear inferred from file locations rather than explicit registration statements visible in the provided code.

• Explicitly register all tools in a central @server.tool() decorator block with full JSON Schema input definitions and documented output schemas. Move examples into a separate 'examples' subdirectory and provide one canonical tool interface.
• Fix the 'add' tool schema: wrap in {'type': 'object', 'required': ['a', 'b'], 'properties': {'a': {'type': 'integer', 'description': '...'}, 'b': ...}}.
• For 'name_shrimp', define the ShrimpTank schema inline or reference it properly. Add 'items' schema to the 'extra_names' array (e.g., {'type': 'array', 'items': {'type': 'string'}, 'description': '...'}).
• Expand descriptions to 50-200 characters with actionable context: 'add' → 'Add two integers and return their sum. Use for arithmetic operations in workflows.' 'fetch' → 'Fetch a webpage and return its text content. Follows redirects, respects 30s timeout. Fails on SSL errors or unreachable URLs, try a simpler URL or check connectivity.'
• Add output schemas for each tool: 'add' returns {'type': 'object', 'properties': {'result': {'type': 'integer'}}}, 'fetch' returns {'type': 'object', 'properties': {'content': {'type': 'string'}, 'status_code': {'type': 'integer'}, 'url': {'type': 'string'}}}, etc.
• Document parameter constraints: 'url' should specify format: 'uri', 'a' and 'b' should specify type and range if needed, 'extra_names' should specify max items and item type.
• Add error recovery hints in tool descriptions or in a separate error_handling field: 'If URL is invalid, try removing query parameters. If timeout, the server may be slow, retry after 5 seconds.'

Inferred effective spec: <=2025-11-25.

• Relies on Logging (deprecated) - log to stderr or use OpenTelemetry