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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds that it returns a revision blueprint and discloses the $15.00 USDC price via x402, giving useful behavioral context about output and cost beyond the annotations.

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 short sentences: the first packs purpose, criteria, and output, the second states price. No redundant words; information is front-loaded and easy to parse.

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 no-parameter tool with no output schema, the description covers the key facets: what copy is reviewed, what dimensions are assessed, the returned deliverable, and the cost. It could more explicitly say how the copy is provided, but given the schema and scope, it is sufficiently complete.

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?

There are no formal parameters in the input schema, and the baseline for zero parameters is 4. The description doesn't need to explain parameter details, but it also doesn't clarify how 'website copy' is supplied, so it doesn't exceed baseline.

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 starts with a specific verb 'Review', identifies the resource 'website copy', and enumerates criteria (audience clarity, value, trust, objections, structure, calls to action), plus the deliverable 'prioritized revision blueprint'. This clearly distinguishes it from sibling tools like content-diff or brief-audit.

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 'Review supplied website copy' gives clear context for when the tool applies, and the criteria list narrows its scope. However, it does not explicitly mention alternatives or when not to use it, so it falls short of a 5.

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