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

Annotations already declare readOnlyHint=true and idempotentHint=true, so safety is covered. The description adds useful domain context: each entry includes name, card-opening style, and colour palette, and templates are fixed after publication. This goes beyond annotations but does not mention pagination or ordering, which is acceptable for a simple list tool.

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?

Three concise sentences, each adding value: the first states the purpose, the second lists entry contents, and the third explains the significance of templates. No fluff, and the purpose is front-loaded.

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 parameters, rich annotations, and an existing output schema, the description is complete. It explains the meaning of the list and the implications of template fixation, which is all an agent needs to invoke the tool 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?

The tool has zero parameters and schema coverage is 100%, so the description needs to add no parameter detail. It appropriately focuses on what the returned entries represent, satisfying the baseline for parameter-free tools.

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 indicates the tool lists invitation templates, describing what each entry contains (name, opening style, colour palette) and the role of templates in invitations. It distinguishes from the sibling 'list_templates' by focusing on invitation-specific templates, though it does not explicitly name the alternative.

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 implies the tool is for viewing available invitation templates before creation, but it does not explicitly state when to use this vs. other tools like 'list_templates' or 'create_invitation'. No exclusions or alternative guidance is provided.

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