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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds genuinely non-obvious context by flagging the call as free and by naming the returned artifacts (input schema, payment configuration), but says nothing about behavior for an unknown or non-paid name.

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?

One sentence, zero waste, and the most decision-relevant fact ('Free:') is front-loaded.

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 trivial read-only, single-parameter tool with no output schema, the description covers purpose and return contents adequately. It still omits the failure mode for unknown/non-paid names, which an agent needs to plan around.

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 description coverage is 0%, so the description must carry the burden; it partly does by implying the single 'name' argument identifies a paid tool. It gives no format, casing, or naming-convention guidance for that value.

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?

Specific verb (describe) plus resource (one paid tool, its input schema and payment configuration), so the agent knows exactly what it gets back. It implicitly contrasts with the sibling 'list', but never names it, so sibling differentiation is left to inference.

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 leading 'Free:' implies this is the zero-cost inspection step to run before invoking a paid tool, which is useful implied guidance. However, it never states when-not to use it or points to 'list' for enumerating tools, so usage remains inferred.

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