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

With no annotations, the description carries the full behavioral burden. It discloses important traits: the x402 payment requirement ($0.040 USDC on Base per call) and the 5-chain cap. However, it omits read-only nature, error/failure behavior, and rate limits.

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, the core capability is front-loaded, and the cost constraint follows. No wasted words.

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 2-parameter tool with no output schema and no annotations, the description names the compared dimensions and the payment model, which is largely sufficient. Return formatting details are understandably left out.

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 50%; the description references both parameters conceptually ('one contract address' and 'up to 5 chains'). That said, the 5-chain limit and same-address assumption already appear in the schema, so the added meaning is marginal.

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 (Compare) plus resource (one contract address across chains) and enumerates what is compared (price, activity, deployment) in one call. This cleanly distinguishes it from the sibling single-chain and aggregate tools.

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 phrase 'in one call' implies the efficiency rationale for using this over per-chain calls, but no alternative tool is named and no when-to-use/when-not conditions are given. Usage is inferable but not explicit.

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