Stablecoin supply and flows

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

Annotations already declare readOnly, idempotent, non-destructive, open-world, so safety is covered. The description adds real behavioral context the annotations don't: exactly which metrics come back, that coverage is limited to the largest USD stablecoins (not all stablecoins), and a caveat that supply change is only a rough proxy. It omits ordering and pagination details, keeping it short of a 5.

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 sentences, front-loaded with the scope and metrics, followed by a brief interpretive caveat. No filler and nothing repeated from the schema or annotations.

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 single-parameter, fully-annotated read tool with no output schema, the description covers return contents and coverage boundaries well, which is the main risk an agent faces here. Missing only minor details like result ordering and default-limit behavior.

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 100% (the single 'limit' parameter is fully documented with default and 1-25 bounds), so the schema does the work. The description adds no parameter-level meaning beyond the 'largest' framing that hints at ordering, which is a baseline 3.

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?

Names a specific resource and scope: largest USD stablecoins by circulating supply, with 1d/7d/30d supply change and market share plus an aggregate total. That is well beyond a restatement of the name. It is a verbless noun phrase and doesn't explicitly contrast with siblings, but the resource is unmistakably distinct from get_price/get_derivatives/get_defi_tvl.

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 closing sentence ('Supply growth is a rough proxy for money entering or leaving crypto') gives interpretive context that implies when the tool is useful, which is better than nothing. However, there is no explicit when-to-use/when-not-to-use guidance and no mention of alternatives such as get_market_overview for broader flows.

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