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

With no annotations supplied, the description carries the full burden and does well: it discloses the paid model, the exact charge ($0.01 USDC on Base or Solana), that no account or API key is needed, and that failed calls are not charged. It omits latency, rate limits, and freshness/caching, which keeps it below 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?

Front-loaded with 'Paid' and the payload summary, then cost, then access terms, in a tight telegraphic style that wastes nothing significant. The raw URL at the end is arguably incidental but costs little.

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 zero-parameter paid price lookup with no output schema, the description covers what is returned, what it costs, how payment works, and the failure-billing policy. The remaining gap is that the shape of the returned fields is not described, though the field names are listed.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description correctly implies the ticker is baked into the endpoint rather than passed as an argument.

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 resource (Peapods Finance / PEAS) and exactly which fields it returns: live USD price, 24h change, market-cap rank. An agent can tell this is the PEAS price lookup versus other buy_tok_* tickers. It stops short of 5 because it never routes against a general alternative such as buy_crypto_price.

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?

Usage context is implied by 'Paid' and the price fields, so an agent knows when it is relevant, but there is no explicit when-not-to-use guidance or named alternative for general multi-asset price checks. The cost and access conditions are stated, which is helpful but not the same as tool selection guidance.

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