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

Annotations already declare read-only, idempotent, non-destructive behaviour, so the safety profile is covered. The description adds genuinely new context beyond them: the report contents (fake coins, volume, repeat creator wallets, 50%+ supply buyers, evidence cases) and the Pro/Wholesale tier gating for the takedown PDF link, which is an access condition not visible in annotations.

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 that leads with the core action and scope before the content list. Dense but every clause names a distinct report section, so little is wasted; the trailing tier note is the only slightly separable piece.

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 carries the full burden of describing return values, and it does so thoroughly by enumerating the report's sections and the tier-dependent PDF link. Combined with annotations covering the safety profile, an agent has everything needed to call it correctly.

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%, with 'brand' and 'days' (default 30, 1-365) fully documented, so the baseline is 3. The phrase 'over a window' loosely maps to 'days' but adds no format or semantics beyond what the schema already provides.

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 (summarise) and resource (impersonation activity against one brand) and enumerates the exact contents of the report. A reader can distinguish it from get_stats, list_brands, and search_alerts 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?

The scope ('one brand over a window') implies when the tool applies, but there is no explicit when-to-use or when-not guidance and no named alternative among the siblings (e.g. search_alerts for individual cases). 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.