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

No annotations are provided, so the description must carry the behavioral burden. It discloses the parallel query behavior and default chain list, which goes beyond what the schema shows. However, it does not mention response format, whether the chains parameter is comma-separated, or what happens with invalid/unrecognized chain names, leaving some behavioral ambiguity.

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 description is two compact sentences, front-loading the primary purpose and defaults before the optional parameter. Every sentence contributes useful information with no fluff or redundant restating of the tool name.

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 one-parameter read-only lookup tool, the description is largely complete: it states the action, defaults, and the optional parameter's purpose. Minor omissions like response shape and chain name validation are acceptable for a simple query tool, especially with a 100% schema coverage.

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%, and the schema's description 'Chains to process' is minimal. The tool description adds concrete semantics: the chains parameter accepts a comma-separated list and includes example values (base, eth). This meaningfully exceeds the schema, despite not documenting accepted chain identifiers in full.

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 states a specific verb (查询/gas价格), a resource (multi-chain gas prices), and clarifies the parallel multi-chain behavior. It distinguishes itself from the many gas-related siblings by naming the default chains and the optional chains parameter, so an agent can tell it apart from tools like x402-gas, x402-gas-price, or x402-gas-compare.

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 description gives clear context on default behavior and the optional chains parameter. It does not explicitly say when not to use it or name alternatives, but among a large family of x402-* tools, specifying defaults and the chains selection is enough to guide correct invocation.

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