GET /plans (Plan)

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

Annotations already indicate readOnlyHint=true and destructiveHint=false. The description adds that the tool supports pagination, that array parameters accept comma-separated values, and that the API has a deprecation timeline for old pagination. This supplements the annotations without contradiction.

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 concise: two sentences and a warning, with no fluff. The first sentence states the purpose, the second explains array behavior, and the third highlights a critical constraint. Front-loaded and 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 the tool's simplicity (3 parameters, no output schema), the description covers the main aspects: purpose, pagination behavior, parameter usage, and a deprecation warning. It does not describe the return format, but the annotations and schema compensate.

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 input schema already covers all parameters with descriptions (100% coverage). The description adds that the limit parameter is required for the new pagination and that array fields accept comma-separated values—information that clarifies usage beyond the schema's base descriptions.

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 'Listagem paginada de Planos' (Paginated listing of Plans), specifying the action (list), resource (plans), and pagination. This distinguishes it from sibling tools like get_plan (single plan) and other list_ tools.

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 provides a critical usage guideline: the limit parameter is mandatory for the new pagination, and not providing it triggers the deprecated old model. However, it does not explicitly contrast with other list_ tools or specify when not to use it.

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