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

Annotations already cover the safety profile (readOnlyHint, openWorldHint). The description adds materially beyond them by disclosing the paid-access model: $0.005 per call via x402 or prepaid credits, and free-trial availability. It does not address the idempotentHint=false annotation, but the payment/auth disclosure is valuable context.

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?

Purpose is front-loaded, and the description stays compact while packing the chain list, return fields, alternative tool, and pricing into a few sentences with 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?

With an output schema present, the return-value enumeration is somewhat redundant, but the description still completes the picture by covering chains, access/pricing, and the safety alternative. An agent has enough to call it correctly.

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 both chain and address fully, including the enum and the 0x/Solana-mint format. The description adds only the chain list, which duplicates the schema, so baseline 3 is appropriate.

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 verb and resource ('Live price of any token') and enumerates the exact return fields, so the function is unambiguous. It names one sibling (/token/safety) but does not distinguish itself from close siblings like token-24h, token-lookup, or token-report.

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 gives one explicit routing rule ('For a full rug-pull check use /token/safety'), which is genuine alternative guidance. However it offers no when-to-use guidance against the many other token-* siblings, leaving the agent to infer selection.

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