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

Annotations already declare readOnly, idempotent, and closed-world, so safety is covered. The description goes further by disclosing what data comes back (hours, phone, rating, reservation flag, packages), which is the main behavioral question for a read tool with no output schema; it omits what happens for an unknown id, but that is a minor gap.

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?

One front-loaded sentence, resource named first, then the returned fields in a compact readable series. Every clause conveys information and nothing is padded.

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 read tool with no output schema, the description covers essentially everything an agent needs: what entity, keyed by what, returning what. Only failure behavior for a missing or invalid restaurant_id is left unstated.

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 a single parameter at 100% schema coverage — including the format, pattern, and provenance note pointing to find_restaurants — the schema carries all parameter meaning. The description adds nothing about restaurant_id, so the baseline 3 applies.

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 gives a specific resource (one Foodly restaurant) and enumerates the payload: location, opening hours, phone, rating, reservation acceptance, and sold packages. An agent can distinguish it from find_restaurants (search) and get_menu (menu items) without opening a schema, though it never names those siblings explicitly.

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?

There is no when-to-use or when-not-to-use guidance in the description. The only routing hint, that the id comes from find_restaurants, lives in the schema rather than the description, so the agent must infer that this is the detail-fetch step after a search.

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