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

Annotations already declare readOnlyHint and openWorldHint, covering the safety profile. The description adds the return fields and window constraints, providing some behavioral context. However, it doesn't disclose potential caveats like symbol validity for spot, and there is a mismatch between the tool's spot nature and the schema's 'Futures' mention, though that's not a contradiction with 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 a single, information-dense sentence. It leads with the core purpose, lists outputs, names the sibling it differs from, and states the use case. No wasted words, though it could be split for readability without losing value.

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 ticker endpoint with only two parameters and no output schema, the description covers the essential aspects: the custom window, default value, and the key alternative. It doesn't mention return format or pagination, but for this simple tool it's reasonably complete. The only gap is the symbol description mismatch, but that's not in the tool description itself.

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?

The schema describes symbol (though incorrectly as Futures) and leaves windowSize without a description. The tool description clarifies windowSize allowed values and default, which helps. However, it doesn't correct the symbol description's mention of Futures, potentially confusing an agent. With 50% schema coverage, the description only partially compensates for the missing parameter documentation.

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 states the tool provides SPOT statistics for a configurable rolling window, lists the returned fields (open/close, high/low, %change, VWAP, volume), and explicitly differentiates it from binance_get_spot_ticker_24hr. The purpose is unambiguous, though the verb is implicit and the schema symbol description mentions Futures, creating minor inconsistency.

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 explicitly contrasts with binance_get_spot_ticker_24hr (fixed 24h) and explains when to use this tool: to read spot momentum at a chosen timeframe without manual derivation from klines. This gives clear context, though it doesn't address every alternative among the many siblings, the key differentiator is covered.

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