Wallet closed trades (open-to-close round trips)

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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered; the description adds genuinely non-obvious behavior — the default 30-day window and the full set of accepted since/until encodings. It stops short of stating truncation behavior when a wallet has more than the 500-row cap, or whether a partial/empty result is possible.

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?

Three sentences, front-loaded with what a row is, then the use case, then the time-window mechanics. No filler, and the most decision-relevant fact (round-trip granularity) comes first.

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?

No output schema exists, and the description compensates by enumerating the returned fields, so an agent knows what it will get. Defaults, format flexibility and the skill-evaluation use case are all present; only deep-pagination edge cases are unaddressed, which is minor for a read-only listing tool.

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 80% schema coverage the baseline is 3, and the description earns above it by documenting the accepted since/until formats (relative units, date, date-time, "now", Unix ms) — the schema only says "Start of window" and leaves until entirely undocumented. It adds nothing on coin or limit, but those are already well described in the 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?

States a concrete verb+resource ("Completed trades for a wallet") and immediately defines row granularity — "each row is a full position from open to close" — which is precisely what separates it from the sibling hydromancer_wallet_trades fill/trade list. The enumerated row fields (entry, exit, size, gross and net PnL, fees, funding, hold time) make the scope unambiguous without opening the 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?

It gives an explicit use case ("Best tool for judging trading skill") with a concrete example question ("what is this wallet's win rate and best coin?"), which is real routing guidance. It never names the alternative (hydromancer_wallet_trades) or states when-not to use it, so the agent must infer the boundary from the row-granularity framing.

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