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

Adds substantial behavior beyond the annotations: the server reloads public Costa Rica catalog facts, unavailable IDs are reported rather than replaced, prices/photos/URLs cannot be supplied by the model, and catalog text is not translated. These are non-obvious mutation-of-nothing, data-provenance and failure-handling traits that annotations alone (readOnly/destructive/openWorld) do not convey.

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?

Front-loaded with purpose, then constraints in a tight sequence with no filler. Some clauses ('reloads public Costa Rica catalog facts', 'catalog text is not translated') repeat the same no-translation idea, so it is slightly denser than needed but still efficient.

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?

An output schema exists, so return-value detail is not required, and the description covers the remaining agent-facing unknowns: ordering, locale behavior, unavailability handling, and the fact that the model cannot inject prices/photos/URLs. Nothing needed to invoke this rendering tool 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?

With only 33% schema description coverage, the description compensates by explaining that IDs are chosen 'in the order to present them' and that presentationLocale is set from the conversation or explicit user choice and does not translate catalog text. The array limits/uuids come from the schema, but the ordering and locale semantics are genuine description-only value.

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?

States a specific verb and resource ('Show read-only visual cards for selected service IDs and/or class IDs') and explicitly bounds the scope against siblings by ruling out search, availability check and booking. An agent can immediately distinguish this from wellfred_search_services or wellfred_service_availability.

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?

Gives clear when-to-use context ('IDs returned by WellFred', order determines presentation) and explicit exclusions ('No search, availability check or booking'). It stops short of naming the alternative siblings an agent should call to obtain those IDs, so routing is implied rather than spelled out.

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