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

Annotations cover the safety profile (write, non-destructive, non-idempotent, open-world). The description adds useful behavioral context beyond annotations: the pack is empty, includes a guide snapshot, and the action is free while generation incurs a separate quoted cost. It does not cover authentication or rate limits, but that is less critical given the annotations.

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?

Two short sentences, front-loaded with the core action and followed by the cost/scope clarification. No wasted words and the most important distinction (free creation vs. quoted generation) is immediately visible.

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 two-parameter creation tool with annotations and no output schema, the description covers purpose, scope, and cost. The only missing piece is parameter-level guidance, but the schema supplies required fields and types, so the definition is largely sufficient for an agent to invoke 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?

Schema description coverage is 0% and the description does not explain either parameter. 'Project-owned' weakly hints at projectId, but the 'name' parameter and its constraints are entirely undocumented in the description, so it fails to compensate for the schema gap.

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 a specific verb (Create) and resource (UI Pack) and clarifies it is an empty pack with its guide snapshot. It also distinguishes this from generation by noting generation is a separate quoted action, which helps separate it from the sibling generate_ui_pack.

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: this creates an empty pack for free, while generation is a separate quoted action. It implies use when you want a free empty pack rather than a paid generation, but it never names the alternative sibling tool or states an explicit exclusion.

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