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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and openWorld. The description adds no behavioral context beyond what annotations provide — no auth requirements, rate limits, side effects, or return format. It only restates the content category.

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 a single, front-loaded sentence with no filler. It is appropriately sized for a simple catalog tool, though the dense jargon in the second half slightly reduces clarity.

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 output schema and no parameters, the description must carry the burden of explaining what the tool returns. It states the categories listed but leaves 'SML x402 paid execution authority' undefined, so an agent lacks a complete picture of the return content or how to use it.

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 takes zero parameters, and schema description coverage is 100%. Per rubric, zero parameters sets a baseline of 4; the description cannot add parameter meaning where none exist.

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 verb (List) and a resource (GhostKey's tools and authority), which is more than a tautology. However, the phrase 'canonical SML x402 paid execution authority' is opaque jargon that an agent cannot easily parse, and there is no differentiation from the sibling tools ghostkey_policy, ghostkey_quote, or ghostkey_status. The core purpose is implied but not fully clear.

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 offers no guidance on when to use this tool versus its siblings. It does not mention prerequisites, exclusions, or alternative tools. Only the content of the catalog is implied.

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