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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds useful behavioral context: the ranking is based on an objective score, an eligibility note is optional, and the tool does not produce medical advice. This goes beyond the structured hints and gives the agent a clearer mental model of the tool's behavior.

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 with no filler. The core purpose, scoring basis, optional note, and important caveat are all packed efficiently, with the ranking behavior front-loaded.

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?

With 7 parameters, no output schema, and sparse schema descriptions, the description needs to explain the ranking inputs and return shape. It provides the overall intent and caveats but does not explain the meaning of key parameters (bmi, monthly_budget_gbp, weight_related_condition, format) or what the returned ranked result looks like. An agent would struggle to invoke this tool correctly for nuanced cases.

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 description coverage is only 43%, and the description must compensate but largely does not. It mentions price, rating, and CQC registration as score inputs, which loosely maps to monthly_budget_gbp, cqc_registered, and medication, but it says nothing about bmi, format, weight_related_condition, or limit. The description does not help an agent understand how these parameters influence ranking or eligibility.

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 names a specific verb ('Rank'), a resource ('UK providers'), and a clear selection criterion ('objective score' based on price, rating, CQC registration). It also differentiates itself from siblings by framing this as comparison rather than retrieval or search, so an agent can distinguish it from get_provider, list_medicines, and search_providers.

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 a clear use context: ranking multiple providers for a medicine, with an explicit disclaimer that it is not medical advice or a recommendation and that a prescriber decides suitability. It does not explicitly name alternatives or state when to prefer search_providers/get_provider, but the ranking-purpose is clear enough to orient an agent.

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