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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, non-destructive, closed-world). The description adds genuinely useful provenance context — the ranking is 'measured rather than opinion' and based on reachability — but says nothing about pagination, default limit, or result ordering ties.

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 ranking criterion and the routing hint are both front-loaded. Every clause earns its place.

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?

There is no output schema, so the description should clarify what comes back; it only implies a ranked list without describing fields or length behavior. With two optional parameters whose defaults are undocumented, an agent knows the intent but not the mechanics of a call.

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 0%, so the description must carry the load, and it largely does not. 'In a city' weakly gestures at the city parameter but never explains the enum values or that city is unrestricted, and the limit parameter (its default, range, or interaction with ranking) is entirely unaddressed.

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 resource and the ranking criterion ('hardest restaurants to book in a city, ranked by how rarely a table is actually reachable'), which is more than a restatement of the name. It implicitly distinguishes itself from siblings like open_now and when_does_it_release by framing itself as a measured difficulty ranking, but never names a sibling to sharpen the boundary.

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 a concrete trigger ('what are the hardest reservations') plus a secondary purpose ('to set expectations'). It does not say when NOT to use it or point to an alternative tool such as when_does_it_release for release timing, so it stops short of full routing guidance.

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