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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds context about the official data source and clarifies the scope (basic insurance only), which is useful but does not disclose additional behavioral traits like pagination or rate limits. It does not contradict 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?

The description is a single, focused sentence that front-loads the core purpose ('Cheapest mandatory basic health insurance premiums') and includes necessary clarifications (multilingual terms, data source) without redundancy. Every clause adds value, and it avoids unnecessary verbosity.

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 6 optional parameters, full schema descriptions, and an output schema, the tool is well-documented. The description covers the primary inputs and purpose, and the source reference adds credibility. It does not describe return structure, but that is handled by the output schema. Minor gaps like pagination or error handling are not critical for a read-only tool with this annotation coverage.

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?

The input schema provides 100% coverage with detailed descriptions for every parameter, so the schema carries most of the semantic weight. The description adds a general statement about the tool's purpose ('for a municipality, age and deductible') and reinforces that all plans are basic insurance, but does not add new parameter-level meaning beyond what the schema already specifies. 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 clearly states the tool returns the cheapest mandatory basic health insurance premiums for a municipality, age, and deductible. It names the resource (premiums), the verb (get/cheapest), and the data source (official FOPH). It distinguishes itself from siblings by focusing on health insurance premiums, and the multilingual clarification ensures the agent knows it's specifically basic insurance.

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 provides clear context for when to use the tool (when a user asks for cheapest basic insurance premiums by place, age, deductible). It does not explicitly name alternative tools or conditions for when not to use it, but the context is unambiguous and distinguishes it from general rate or coverage tools like swiss_rates or swiss_coverage.

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