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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is fully covered structurally. The description adds nothing beyond that: it never says how many locations are returned, how 'top-performing' is ranked (scans? unique users? over what window?), or how results are ordered, which is the kind of context this tool actually needs.

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?

A single front-loaded sentence with no filler or redundancy. It is appropriately sized, though at one clause it carries no extra operational detail.

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 values need not be explained, and all five parameters are documented in the schema with conditional requirements spelled out. The tool's scope combination logic (idproject shared between project and qrcode) is covered by the schema, leaving only ranking/result-size semantics unaddressed.

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 coverage is 100% and the schema descriptions are unusually rich, including the conditional requirement that idqrcode is needed when scope=qrcode and the date-omission rules for start_date/end_date. The description adds no parameter detail beyond the schema, so the baseline 3 is correct.

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?

Specific verb (fetch) plus resource (top-performing location analytics) with the three supported scopes named, which lets an agent distinguish it from generic scan-listing siblings like get_scans_by_date. It does not, however, differentiate itself from closely related siblings such as get_scans_by_country or get_scans_by_region, which also return geographic performance data.

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?

Enumerating the account/project/qrcode scopes implies when the tool applies, but there is no explicit guidance on when to choose this over get_scans_by_country, get_scans_by_region, or get_top_performing_date. Usage is inferable but not stated.

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