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

Beyond the readOnly/idempotent annotations, the description discloses meaningful behavior: boards not yet in the database are fetched live, App Store and Google Play boards are live store boards rather than keyword lookups, and rate-limited or quota-exceeded requests return a plan-limit message. No contradiction with 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?

The description is dense but every sentence earns its place: purpose is front-loaded, then category behavior, sort/window semantics, live-fetch behavior, sibling alternatives, and a rate-limit note. No filler or repetition of the schema's enums.

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 complex tool with seven parameters and no output schema, the description covers the key operational details an agent needs: feed type restrictions, category requirements, sort and window behavior, live fetching, alternative tools for history, and rate-limit response behavior. Nothing critical is missing.

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?

The input schema already documents all seven parameters thoroughly, so the bar is high. The description adds useful parameter-adjacent context about `sort`/`window` semantics, the role of `category` in selecting boards, and the fact that some types are live store boards rather than keyword lookups, though much of it echoes the schema.

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?

The description states a specific operation: return the live top-trending board for exactly one feed type, with no keyword. It also clarifies which feed types require a category and distinguishes this tool from history-style siblings by noting live boards are only available here, not via get_time_series.

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?

It provides explicit when-to-use guidance: use category for specific board types, use sort='rank_change' for climbers over a window, and use get_growth or get_time_series for app history. It also states a clear when-not: live boards are not available via get_time_series.

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