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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the default asset scope and input format, but says nothing about rate limits, auth, or comparison behavior beyond what annotations and the output schema already imply.

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?

Two compact sentences, purpose front-loaded before the parameter note, with no filler. Efficient, though terse enough that the missing top_n explanation is a structure gap rather than excess.

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?

An output schema exists, so return values need not be explained, and annotations cover safety. For a 2-parameter tool it is nearly complete, but the undocumented top_n and absent when-to-use guidance leave meaningful gaps.

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 description coverage is 0%, so the description carries the full burden. It documents 'assets' as a comma-separated list with a default (though the default is already in the schema), but 'top_n' is never mentioned, leaving half the parameters 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?

States a specific verb (compare) and resource (tops of BTC/ETH/SOL/BNB arenas) with a clear goal (cross-asset pattern hunting). An agent can distinguish it from leaderboard-style siblings by the cross-asset comparison angle, but no sibling is explicitly named or contrasted.

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 rationale 'pour chasser des patterns cross-asset' implies when the tool is useful, giving more than pure silence. However, it names no alternatives and no when-not-to-use conditions (e.g., vs arena_leaderboard or arena_snapshot), leaving routing to inference.

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