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

Annotations already establish read-only, idempotent, non-destructive behavior. The description adds useful behavioral context beyond annotations: it explicitly states that usage does not count toward monthly searches, which is a quota-impact trait not present in structured metadata. It also clarifies return content. This exceeds the minimum, but lacks details on errors or response format.

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 concise sentences, front-loaded with the primary purpose. Every sentence adds value: the first states the action and the second explains the output and a key behavioral caveat. No wasted words.

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 zero-parameter, read-only tool, the description is fully complete. It tells the user what the tool does, what it returns, and a relevant quota behavior. The annotations cover safety, and no output schema is needed. Sibling tools are not similar enough to require further disambiguation.

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 baseline is 4. The description doesn't need to explain parameters, and the schema is trivially complete. No additional parameter semantics are required.

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 clearly states the tool's purpose: 'Get pricing for all plans.' It specifies the verb and resource, and also outlines what is returned ('names, prices, features, limits'), making it distinct from sibling tools like get_pack_link or get_upgrade_link. The inclusion of 'all plans' provides additional scope.

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 implies use when pricing information is needed, and the note 'Does not count toward your monthly searches' gives context about when to use it relative to quota. However, it does not explicitly name alternatives or state when not to use it, which prevents a 5.

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