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

Annotations already declare read-only, open-world, non-destructive behavior. The description adds valuable return details (total_available count, OHLCV, % change) and notes sorting/filtering behavior, though it omits data freshness or rate limits.

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 front-loaded with purpose, then structured into Args and Returns sections. Every sentence earns its place, with no redundant or filler text.

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 four parameters, no output schema, and annotations covering safety, the description is complete: it explains the tool's purpose, all parameter semantics, and the return structure. The only minor gap is the lack of explicit sibling comparison, which is handled in the usage dimension.

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 0%, so the description must carry the full burden. It does so thoroughly by listing all four parameters with allowed values, defaults, and filtering semantics (e.g., category enums, exchanges options, limit default 30, volume_min 0 = no filter).

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?

States a clear resource and scope: top futures contracts sorted by trading volume. This sorting criterion implicitly differentiates it from siblings like futures_top_movers, but no sibling is named explicitly.

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?

Provides detailed parameter options for filtering, effectively implying how to use the tool (e.g., by category or exchange). However, it offers no explicit guidance on when to choose this tool over alternatives such as futures_top_movers or futures_category_snapshot, nor any exclusions.

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