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

Annotations already mark the tool as read-only, so the description only needs to add extra behavioral context. It adds 'Always free' and notes that pricing/allowance data is returned, but it does not discuss pagination, limits, or other runtime behavior.

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 front-loaded with the core action, packs useful detail into each phrase, and avoids filler. The category list is long but directly helps an agent choose a category_id.

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 simple one-optional-parameter listing tool, the description is largely complete: it states what is returned, that it is free, and how to use it as an entry point. The lack of an output schema is mitigated by listing the returned fields, though exact response shape is not specified.

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 description coverage is 100%, so the baseline is 3. The description's category list reinforces the category_id parameter with additional examples, but it doesn't clarify exact accepted values or format beyond what the schema already provides.

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 identifies the resource (stock screens), the operation (browse by category), and the returned fields. It does not explicitly name sibling tools to differentiate against, though 'Start here to find a screen id' implies it is the catalog entry point.

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 gives clear context: use this tool as the starting point to find a screen id, and it is always free. It does not explicitly mention when not to use it or name alternatives like get_smart_list for retrieving a specific screen.

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