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A remote MCP server providing calculator tools without authentication, deployed on Cloudflare Workers
Two tools with basic schemas and minimal descriptions. Both tools have input schemas with proper types (number, string enum), but descriptions are extremely short (10-40 chars), falling well below the 50-200 char baseline for LLM-optimized descriptions. No output schema documentation. Error handling exists (divide-by-zero check) but lacks recovery guidance. Tool names are action-oriented (add, calculate) but lack verb prefixes. No parameter descriptions beyond type info.
Simple addition tool
Calculator tool with multiple operations
Tool descriptions critically short (10-40 chars). 'Simple addition tool' and 'Calculator tool with multiple operations' lack context for LLM selection. Should explain WHAT the tool does, WHEN to use it vs alternatives, and what it returns.
No parameter descriptions. Parameters 'a', 'b', 'operation' have types but no descriptions explaining their meaning, constraints, or expected format. LLMs cannot infer that 'operation' is an enum of arithmetic operations without explicit text.
No output schema documented. Tool responses return text content, but LLMs have no formal schema describing the response structure, field names, or types. This forces LLMs to parse unstructured output.
Error handling lacks recovery guidance. Divide-by-zero returns 'Error: Cannot divide by zero' but does not guide the LLM on next steps (retry with different input, use add instead, etc.).
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-23 | D | 55 | 2026-07-28+ | v2 |
Tool names lack action verbs. 'add' and 'calculate' are nouns/verbs but do not follow verb_noun convention (e.g., 'perform_addition', 'perform_calculation'). This reduces clarity when many tools are available.