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

Annotations already establish this as a safe, read-only, idempotent operation, so the description's additional burden is low. It adds meaningful behavioral context by explaining the ranking methodology: averaging each currency's move across every pair in the basket and ordering by strength. No contradictions with annotations were found.

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 deliver the core purpose, the calculation methodology, and the output ordering with no redundancy. The key term 'strength leaderboard' is front-loaded, and the next sentences earn their place by clarifying what 'strength' means.

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 simple read-only tool with two optional parameters and no output schema, the description covers the essential needed details: time window, basket choices, computation, and return ordering. It is slightly incomplete in not specifying the return label format or whether moves are expressed in percentages or pips, but this is a modest gap given the tool's low complexity.

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 input schema has 0% description coverage, so the description must compensate. It does so by explaining that 'basket' limits the leaderboard to g10 or majors and that 'past N days' maps to horizon_days. This gives semantic meaning beyond the raw enum/default values, though it stops short of defining exact move units or basket membership details.

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 and deliverable: a 'ranked strength leaderboard' over the past N days. It further specifies the resource (g10 or majors basket) and the output structure (strongest to weakest, per-currency label), making it clearly distinct from related FX tools like fx_volatility_leaders.

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 phrasing 'ranked strength leaderboard' implies the tool is for comparing relative currency strength over a horizon, and the description gives methodological context. However, it does not explicitly say when to use this tool versus alternatives such as fx_movers, fx_correlation, or fx_volatility_leaders, nor does it name exclusions.

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