futures_top_movers

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is established. The description adds useful behavior beyond the annotations: the return payload (list ranked by % change with OHLCV data) and the semantic of volume_min (filters illiquid contracts), which clarifies default behavior an agent would otherwise have to infer.

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 six-line summary sentence is front-loaded before the Args block, and the compact parameter listing is scannable and free of fluff. The only minor gap is 'max results' being slightly terse (max what? limit of results is implied but could be explicit).

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 read-only, parameter-simple tool, the combination of annotations, parameter documentation, and return description is nearly complete—an agent can call this tool correctly with the given information. It would only be improved by noting how it differs from the many similar siblings (e.g., futures_market_overview, futures_category_snapshot) in its domain.

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?

With 0% schema description coverage, the description carries the full burden of documenting parameters, and it delivers. All four parameters are given meaningful semantics: direction maps to gainers/losers with value options, exchanges maps to us/global, limit is explained as max results, and volume_min gets default plus behavioral context. This is exactly how a description should compensate for a bare schema.

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 summary line "Futures contracts with the biggest percentage moves today" uses an implicit but clear verb plus resource, and the Returns section confirms it lists futures ranked by % change. However, it doesn't differentiate itself from closely-related siblings like top_gainers, top_losers, futures_market_overview, or futures_category_snapshot that could easily be confused with this tool.

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 Args/Returns sections explain what the tool does with each parameter, but there is zero guidance on when to choose this tool over its many overlapping siblings. Given siblings like top_gainers, top_losers, futures_watchlist, and futures_market_overview, the description leaves an agent guessing which sibling to invoke when a user asks for top movers versus market overview data.

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