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

No annotations are provided, so the description carries the transparency burden and does well: it discloses that all L2 RPCs are queried in parallel and states a concrete cost of $0.002 USDC per call. It does not cover failure modes, rate limits, or latency expectations, which keeps 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?

Three tightly written sentences, front-loaded with the core action and immediately followed by outputs, execution behavior, and cost. Every sentence adds useful information.

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 no input schema, no output schema, and no annotations, the description must carry the full burden. It does so by explaining the comparison scope, the returned metrics, parallel RPC execution, and per-call pricing.

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 has zero input parameters, so the baseline is 4. The description correctly presents this as a no-argument comparison operation and does not suggest any missing inputs.

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 and resource: compare gas costs across 8 L2 chains in real time. It also scopes the tool to L2 chains, which distinguishes it from broader gas tools like gas_tracker and priority_fee, and it enumerates the returned fields.

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 comparison use case is clearly implied by 'Compare gas costs across 8 L2 chains,' but the description does not explicitly say when to choose this over siblings such as gas_tracker or priority_fee. There are no exclusions or alternative-routing guidance.

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