Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare read-only and idempotent traits. The description adds the term 'canonical' and implies authoritative search behavior. No contradiction, but lacks details on edge cases (e.g., no results). Still sufficient given annotation coverage.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, no wasted words. Front-loaded with the core purpose. Every sentence adds value: first defines identity, second provides usage context.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a search tool with 4 fully described parameters, an output schema present, and no nested objects, the description is complete. It covers purpose, usage, and search modes without missing critical information.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% with well-described parameters. The description adds value by explaining the search modes ('exact codes, clinical terms, or consumer phrases') and emphasizing it's the canonical tool, which is not in the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('search'), resource ('CPT/HCPCS index'), and scope ('canonical code-lookup tool'). It explicitly distinguishes from sibling pricing tools by positioning it as the first lookup.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicit guidance: 'Use this first when the user does not already know the CPT code, before calling pricing tools.' This clearly defines when to use and hints at alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.