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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds only the returned metric set (PnL %, trades, win rate) and the 'limit max 30' cap, both of which are marginal given the presence of an output schema and the schema's maximum. No auth, refresh/rate-limit or staleness behavior is described.

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 tight, front-loaded sentences: the resource and default asset come first, then the limit constraint, then the sibling routing hint. Nothing is padded, though the description is in French while the surrounding tool surface (siblings, schema titles) is English, which is a minor friction cost for an agent reading the toolset.

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?

With full annotations, an output schema and a single optional parameter, the definition covers what the agent needs to call it correctly: what it returns, the default asset, the limit cap, and where to go for multi-asset comparisons. Missing only a hint of when it beats near-neighbors like arena_snapshot or community_arena_rankings.

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% for the single 'limit' parameter, so the description carries the burden, yet 'limit max 30' merely restates the schema's maximum/default rather than explaining that it caps the number of ranked strategies returned. It gives a hint of the parameter's role but adds no real meaning beyond the structured field.

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 resource and scope: a live arena leaderboard of the best AI strategies, defaulting to BTC, showing PnL %, trades and win rate. It also differentiates itself from siblings by naming compare_arenas and list_arena_strategies for the multi-asset case, so an agent can route without opening either schema.

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?

Explicitly names the alternative tools ('compare_arenas ou list_arena_strategies') and the condition that selects them (multi-assets), which is genuine when-to-use guidance. It does not state when this tool should be preferred over arena_snapshot or community_arena_rankings, so the routing picture is incomplete but clearly useful.

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