Coin Kings

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

Annotations already establish read-only, open-world, idempotent, non-destructive behavior. The description adds meaningful behavioral context by explaining the perCoinRank semantics (1 = king only, higher = top-N) and listing the exact returned fields, which helps the agent understand what the invocation will yield.

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 compact and front-loaded. The main action comes first, then parameter behavior, return fields, and use-case examples. Every sentence adds value and there is no filler.

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?

The description covers the tool's ranking semantics, returned fields, and typical user questions. With full schema parameter documentation and annotations, this is sufficient for an agent to select and invoke the tool correctly, though it could be slightly stronger by naming related sibling tools for clearer routing.

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 coverage is 100%, so the schema already documents all four parameters. The description reinforces the meaning of perCoinRank with an example ('1 returns only the #1 earner'), but it adds no additional meaning for limit, offset, or useToonFormat beyond what the schema already provides.

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 opens with a precise verb-object-purpose phrase: 'Find the top earner(s) per coin within the window.' It defines the core concept 'king' and frames the query around 'who owns BTC?' / 'who is the best trader of each market?', making the tool's scope clear and distinct from sibling leaderboard-style tools.

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 explicitly states what questions the tool answers: 'who owns BTC?' and 'who is the best trader of each market?'. This gives an agent clear contextual guidance, though it does not explicitly name sibling alternatives or state when not to use this tool.

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