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

With no annotations, the description carries the full burden, and it does disclose useful traits: per-request pricing ($0.005000/call), the x402 USDC payment mechanism, and that depegged coins are flagged. It omits error behavior (e.g., unknown symbol) and any return-shape or pagination expectations, so meaningful gaps remain.

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 opening clause 'Stablecoin market in one route: ...' and the three data modes are stated twice, with the first pass adding essentially nothing before the richer second pass. Use cases and pricing are front-loaded toward the end rather than leading. Roughly a third of the text is redundant.

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 annotations and no output schema, so the description must carry everything; it covers modes, parameters, cost, payment, and trigger phrases. An agent has enough to invoke it correctly, though the always-required symbol for non-peg views remains unaddressed.

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 0% and neither parameter has an enum, so the description is the only source of meaning. It supplies the valid view values (overview, peg, chains) and demonstrates symbol usage via symbol=USDC, which compensates well. It does not explain why symbol is required even for the overview and chains views, which is a residual ambiguity.

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 names a specific resource (stablecoin market data) and enumerates three distinct modes: top coins by supply, peg health for one coin, and supply per blockchain. An agent can distinguish it from siblings like crypto_market or token_price-history. It stops short of an explicit sibling comparison, but the verb/resource pairing is unambiguous.

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?

Offers concrete trigger phrases ('is usdc still pegged', 'top stablecoins by market cap', 'stablecoin supply per chain') that map directly to the view modes. It states when each view applies (overview / peg+symbol / chains) but never names an alternative tool or a when-not condition.

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