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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description only needs to add beyond that. It discloses the paid-request behavior and the $0.35 USDC cost, and indicates it is 'standard' preflight (vs premium). However, it does not describe response format, error behavior, or what a successful batch outcome looks like, leaving some behavioral gaps.

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 sentences: one stating the action and scope, the other providing price and an example endpoint. It is tightly written with no filler, front-loading the core purpose.

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?

The tool has a single parameter and helpful annotations, but no output schema. The description covers what it does, cost, and an example, yet omits what the response looks like and how failures are handled. It is adequate for a simple tool but leaves some contextual gaps.

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 only parameter 'urls' is semantically explained as the URLs against which preflight runs, and the 'up to 10' limit matches the schema's maxItems. The description provides some compensation for the 0% schema coverage, but it largely repeats the schema and does not add deeper details like URL format expectations or behavior for invalid URLs.

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 clearly states the tool's action ('Run standard preflight'), its scope ('against as many as 10 URLs'), and its paid nature, distinguishing it from a single-URL preflight tool. The verb and resource are specific, leaving no ambiguity about what the tool does.

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 implies when to use this tool (when you need to preflight multiple URLs in one request) and provides the cost context. However, it does not explicitly name alternatives like 'preflight' or 'premium_preflight', and does not state when not to use it, so it lacks explicit exclusions.

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