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

Annotations already state readOnlyHint and destructiveHint, so the description correctly avoids repetition. It adds value by disclosing return behavior ('Returns each field's name and data type') and the edge case ('An empty object means...'). It also states the requirement for a brand_template_id, though the param name mismatch with schema is a minor flaw.

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 organized into three short paragraphs: purpose, usage, and return details. It is front-loaded with the core action and avoids excessive fluff, though the second paragraph could be merged with the first for tighter structure.

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 read-only tool with one required param, the description covers the return format and the empty-object case. It also clarifies scope ('Not for an individual existing design'). The only notable gap is the param name inconsistency ('brand_template_id' vs 'template_id'), which could confuse an agent.

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 schema fully documents both parameters. The description adds no additional parameter-level meaning beyond restating that 'brand_template_id' is required, which actually conflicts with the schema's 'template_id' naming. This does not improve on schema coverage.

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 with a specific verb ('Determine... list') and resource ('Brand Template'). It explicitly differentiates from sibling tools by noting 'Not for an individual existing design,' which sets it apart from get-design and similar 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 clear usage scenarios ('Use to check if the template can be populated with data...') and an exclusion ('Not for an individual existing design'). It does not name a specific alternative sibling, but the guidance is sufficient to route the agent appropriately.

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