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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered; the description adds value by citing the upstream source (lu.ma/discover) and flagging that event_count is live rather than static. It does not mention caching, rate limits, or how fresh the city set is, which would have pushed it to a 5.

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, no filler, with the payload description front-loaded before the routing advice. Every clause carries information the agent needs.

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 no output schema, the description steps in and enumerates the returned fields (place_id, coordinates, event_count). Purpose, return shape, and placement relative to luma_events are all covered for a simple two-optional-param read tool.

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 100% — both limit (range/default) and query (substring semantics with a worked example) are fully documented in the schema. The description adds no parameter-level detail beyond the implicit framing of results as cities, 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?

States a specific verb and resource ('List Luma's curated discover cities') and pins down the payload (place_id, coordinates, live event_count). It also names the downstream sibling luma_events, so the agent can place this tool in the workflow without opening any schema.

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?

Explicitly gives the condition for calling it (need a place_id for luma_events) and the condition for skipping it (just pass a city name to luma_events directly). That is a rare, unambiguous when/when-not pair with the alternative named.

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