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

Annotations already indicate read-only, idempotent, and non-destructive behavior. The description adds valuable behavioral context: returns specific fields (name, description, type, category), mentions that custom templates are always included, gives category breakdown, and explains category filter scope. No contradictions.

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 and well-structured: a single sentence for core purpose, a bulleted list for usage scenarios, and a sentence explaining return fields and category usage. No unnecessary information.

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?

The description covers what the tool does, when to use it, and what it returns. Given the simplicity of the tool (2 optional params, no output schema, strong annotations), it is nearly complete. Minor omission is explicit mention of return format (likely an array), but not critical.

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% with both parameters well-described. The description reinforces usage of the optional category filter for recommendations and reiterates that custom templates are always included. This adds slight context beyond the schema but doesn't introduce new parameter details.

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 'List all 15 built-in MDMagic templates plus any custom templates the user has uploaded.' It specifies the action (list), the resource (templates), and distinguishes from sibling tools like list_builtin_templates and list_custom_templates by being the combined version. The title from annotations reinforces this.

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 explicitly lists four proactive call scenarios: when user mentions a template by name, asks what's available, when convert_document fails, or when user describes a look. It also suggests using the category filter to narrow recommendations. This provides clear guidance on when to use this tool versus alternatives.

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