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 new behavioral context the annotations cannot convey: a $0.002 USDC charge per successful call via x402 on Base/Solana/Arc, and that failed calls are free — critical for an agent deciding whether to spend. It omits pagination/caching behavior, keeping it from 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 tight sentences with the payload description front-loaded and cost terms second; no filler. It could be marginally tighter by not repeating the 1–100 range already present in the schema.

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 tool is simple (one optional param, output schema present, read-only annotations), and the description covers scope, fields, and the payment model. Nothing essential for correct invocation is missing; only comparative guidance against the crowded crypto-price sibling set is absent.

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% and the single 'limit' parameter is already documented with its 1–100 range and default of 10. The description restates the same range without adding format or edge-case guidance, so the baseline 3 applies.

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 gives a concrete verb and resource — a ranked CoinLore crypto list — and enumerates the exact fields returned (USD price, market cap, 24h volume, 1h/24h/7d changes) plus the limit range. It identifies the data source (CoinLore), which separates it from generic price siblings, though it never explicitly contrasts itself with tools like finance_coinmarketcap or finance_coingecko.

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?

There is no statement of when to pick this over the many sibling ticker/listing tools (CoinGecko, CoinMarketCap, CoinPaprika, exchange tickers). The 'top N coins' phrasing hints at a ranked-market-overview use case, but the agent must infer that; no exclusions or prerequisites are given.

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