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

With annotations already declaring readOnly, idempotent, and non-destructive behavior, the description adds useful context: it is an aggregated snapshot rather than a live oracle, signaling possible staleness. The explicit $0.001 USDC per-call cost is important behavioral information not present in 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 compact and well-structured: the first sentence states what data the table contains, the second delivers the critical caveats (aggregator snapshot, not oracle) and cost. Every sentence earns its place with no redundant filler.

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 there is no output schema, the description adequately lists the returned fields and notes the paid nature and snapshot behavior. It is slightly incomplete around defaults for the optional 'limit' parameter and response shape, but for a simple list tool with strong annotations this is a minor gap.

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 only 50% since the 'limit' parameter has no schema description, and the tool description adds no parameter explanations. The 'vs' enum is self-explanatory, but the meaning of 'limit' — such as default value or whether it caps the number of rows — is left undocumented in both schema and description.

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 clearly identifies the tool as a market-cap ranking table and enumerates the exact data fields (price, market cap, volume, 1h/24h/7d change). It is distinct in intent from the many exchange-specific market_* siblings, though it does not explicitly name an alternative to differentiate itself.

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 contextual guidance by calling itself a public aggregator snapshot, not an oracle, which warns against using it for settlement-grade price data. It also flags the per-call cost, but it does not explicitly describe when to prefer this over other market tools or what situations to avoid.

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