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

Annotations already declare readOnly, openWorld, idempotent, and non-destructive behavior. The description adds valuable context beyond those: it is 'not authoritative or diagnostic,' it 'uses Loa heuristics plus AI,' and it requires signing in to Loa. These traits materially affect how an agent should present results and handle auth, with no contradiction of the annotations.

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?

Three sentences with zero waste: the core purpose is front-loaded, followed by the key caveat, then usage and alternative routing. Every sentence earns its place and no annotation facts are redundantly repeated.

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 single-parameter advisory tool with a full output schema and clear annotations, the description covers purpose, limitations, auth requirements, the follow-up confirmation step, and the no-sign-in fallback. Nothing an agent needs to invoke it correctly is missing.

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%, so the schema fully documents the single query parameter with examples. The description reinforces the idea of a 'plain-English medical need,' but does not add syntax, format, or edge-case semantics beyond what the schema already provides. Baseline 3 is appropriate.

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 states a specific verb and resource: 'suggests likely CPT codes from a plain-English medical need.' It also differentiates itself from the sibling search_cpt_codes by explicitly limiting use to when 'the user cannot name the procedure,' so an agent can distinguish them without opening schemas.

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?

The description gives explicit when-to-use ('Use only when the user cannot name the procedure'), a required follow-up action ('confirm candidates with search_cpt_codes before pricing them'), and a clear alternative for the unauthenticated case ('without sign-in, use search_cpt_codes with consumer phrases instead'). This is complete routing guidance.

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