Top gainers/losers

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint. The description adds that it returns 24h movements within a segment, which is consistent. However, it doesn't disclose additional behavioral traits like pagination or response structure beyond what annotations cover.

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?

Single sentence, no redundant information. Efficient and front-loaded with the core action.

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 presence of an output schema and rich annotations (idempotent, read-only), the description is largely adequate. However, it doesn't explicitly state that both gainers and losers are returned, but this is implied. Slight gap for a completely self-contained description.

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 coverage is 100%, so baseline is 3. The description does not add meaning to parameters beyond what the schema descriptions already provide (e.g., 'limit' and 'segment' defaults).

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 'Biggest 24h gainers and losers within a rank segment' clearly states the tool's function with a specific verb (gives) and resources (gainers/losers) and scope (rank segment). The title 'Top gainers/losers' aligns with this, clearly distinguishing it from siblings like 'top_coins' or 'coin_markets'.

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?

No explicit guidance on when to use this tool versus alternatives like 'top_coins' or 'coin_markets' for trending data. The description does not mention contexts where it is appropriate or inappropriate, leaving the agent to infer from the name alone.

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