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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false), so the description's added value is noting that data is real-time and ranked by market cap. It does not discuss potential caveats like data freshness limits or pagination, but the annotations lower the burden for this simple read-only tool.

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 a single, tight sentence with no filler. It front-loads the core purpose and then lists the returned fields efficiently, making it easy to scan.

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 one-parameter, read-only tool with an output schema and safe annotations, the description is nearly complete. It lacks explicit sibling routing, but the schema covers the limit parameter and the output schema handles return details, so only minimal contextual guidance 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 schema already fully describes the only parameter, limit, including its default, range, and purpose. The description restates the market-cap ranking context but does not add new parameter meaning beyond what the schema provides, so a baseline score of 3 is appropriate.

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 uses a specific verb ('Get') and a clear resource ('top cryptocurrencies ranked by market cap'), and names the exact fields returned: real-time price, 24-hour change percentage, and market cap. This distinguishes it from siblings like assets-info or assets-search, which target specific assets or queries rather than a ranked top-N list.

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 description implies the use case: when you want a market-cap-ranked list of top assets. However, it does not explicitly state when not to use it or mention alternatives such as assets-info or assets-search, so the agent must infer routing from the sibling names.

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