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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the return-field list but does not reveal additional behavioral traits like rate limits, endpoint selection, or keyless vs. API-key behavior; those details appear only in the parameter schema, not the description.

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, efficient sentence that front-loads the core action and result fields. It contains no filler or redundant information, every phrase earning its place.

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?

Given the low complexity, rich annotations, 100% schema coverage, and the presence of an output schema, the description is complete. It conveys the purpose, sorting basis, and returned fields, leaving no significant gaps for an agent to invoke the tool 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%: both 'limit' and '_apiKey' have meaningful descriptions, including default values and optionality. The main description adds no parameter-level meaning beyond what the schema already provides, so the baseline score of 3 applies.

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 the exact operation: 'Get top cryptocurrencies ranked by market cap' and enumerates the returned fields. This clearly distinguishes it from sibling tools like get_crypto_price, get_crypto_history, and get_crypto_global by specifying the ranking scope and data fields.

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 a use case—retrieving a market-wide ranked list—but provides no explicit when-to-use or when-not-to-use guidance. It does not mention alternatives or exclusions, so the agent must infer appropriate usage from the tool's purpose.

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