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

Annotations already declare readOnlyHint=true and idempotentHint=true, covering the safety profile. The description adds context that the data is 'canonical and public,' but this is more about data nature than behavior. It does not contradict annotations and adds minimal behavioral insight beyond them, which is acceptable given the high annotation coverage.

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 with no redundancy. The main usage is front-loaded in the first sentence, and the exclusion is stated in the second. Every word contributes value with no waste.

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 tool with no parameters, rich annotations, and an output schema, the description is adequately complete. It states the purpose and the boundary of use. The only minor gap is not specifying what the output contains, but the output schema covers that. Overall, it provides enough for an agent to call it correctly.

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 has zero parameters, so the schema fully defines the input. The baseline for a zero-parameter tool is 4, and the description does not need to add any parameter explanation. It is sufficient.

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 the tool provides BetterOff's canonical public pricing facts and assumptions, which gives a specific resource and intent. It implicitly means the tool returns those facts, though it doesn't use a direct verb like 'retrieve' or 'return'. It clearly distinguishes from customer billing/account data, which helps separate it from other tools, though no sibling has a directly similar name.

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?

Explicitly provides both when to use ('when an agent needs... public pricing facts') and when not to use ('Do not use for customer billing or account data'). This gives clear context and an exclusion. While no specific alternative tools are named, the boundary is set, satisfying the criterion for explicit when/when-not guidance.

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