list_plans

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

Without annotations, the description provides details on output (pricing in 8 currencies, AI credit allowance, feature bullets, signup URL) and notes the pricing document version and tier structure, though rate limits or auth needs are not mentioned.

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 relatively long but each sentence adds value, front-loading the core purpose. Minor redundancy could be trimmed, but it remains efficient.

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?

Given no output schema, the description covers the response comprehensively: pricing, tiers, add-ons, features, signup URL, and even references the pricing document version, leaving little ambiguity.

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 coverage is 100%, and the description adds context: for 'country', it explains ISO code filtering and the option to omit for all markets; for 'plan', it clarifies restricting to a single tier, enhancing the schema enums.

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 it lists HelloBooks pricing plans with specific details on currencies, tiers, add-ons, and features, distinguishing it from sibling tools like list_features or list_credit_packs.

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?

It indicates optional filters for plan and country but does not explicitly state when not to use this tool or suggest alternatives, though the context is clear given the sibling set.

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