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 externally. The description adds useful operational defaults (days=30, limit=10) but says nothing about return shape or pagination, which is acceptable given the annotation coverage.

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?

Extremely dense and front-loaded: the core action and scope lead, followed by metric, direction, and limit defaults in telegraphic fragments. Every clause carries information, though the fragmentary style is slightly clipped.

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 read-only ranking tool with no output schema and annotations covering the safety profile, the description supplies the key knobs and defaults an agent needs to invoke it correctly. Only brandId scope is left implicit, which is minor for a self-evident identifier parameter.

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 schema description coverage at 0%, the description compensates well by supplying defaults absent from the schema (days=30, limit=10, direction=top) and the max for limit. It does not explain brandId or why days is capped at 365, but most parameters are given meaning beyond the raw types and enums.

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 (Rank) and a clearly scoped resource: the brand's videos published in the last N days, ordered by a named metric. An agent can tell what it produces without opening the schema, though it does not explicitly distinguish itself from close siblings like get_performance_summary or get_recommended_videos.

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?

Usage is implied by the mechanic (rank videos by metric over a time window) but there is no explicit when-to-use, when-not-to-use, or named alternative. An agent must infer that this is the tool for leaderboard-style ranking versus aggregate metrics.

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