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

Annotations already declare readOnlyHint, idempotentHint, closed-world and non-destructive, so safety is covered. The description adds value annotations cannot: the actual content of the response (price point, trial duration, cancellation terms), which is the key behavioral fact for a lookup tool with no output schema.

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?

A single sentence, front-loaded with the resource and immediately followed by the concrete contents. No filler, no repetition of the name or title.

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, the description carries the return-value burden and does so by naming the three data points returned. It is nearly complete; only the response format (structured fields vs. prose) is unspecified, a minor gap for a static-information tool.

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?

Zero-parameter tool with an empty, closed schema, so the baseline of 4 applies. The description correctly implies no inputs are needed to retrieve the pricing.

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?

States a specific verb and resource ('Return Grey Tabby Golf pricing') and enumerates the exact payload — monthly price, trial length, cancellation terms — so an agent knows precisely what comes back. It does not explicitly distinguish itself from the sibling start_trial, which also concerns the trial, so it stops short of a 5.

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?

Usage is only implied: an agent that needs price or cancellation information will infer this is the tool, but there is no statement of when to use it, and no routing guidance such as 'use start_trial to actually begin the trial' despite that sibling existing.

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