Browse Apple HIG topics by category to retrieve titles, slugs, and summaries for design reference. Omit the category filter to list every indexed topic.
List all topics within a specific category with their titles, slugs, and summaries.
| Name | Required | Description | Default |
|---|---|---|---|
| category | No | Optional category name to filter by (e.g. "Foundations", "Components", "Patterns", "Platforms"). If omitted, lists all indexed topics. |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations exist, so the description carries the full burden; it does disclose the shape of returned records (titles, slugs, summaries), which is real value. However it says nothing about pagination, result caps, ordering, or whether a nonexistent category returns empty or errors.
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?
One sentence, front-loaded with the action and resource, with the return contents appended. There is no filler and nothing is buried.
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 listing tool with a fully documented single parameter and disclosed return fields, the description is nearly sufficient. The remaining gap is operational detail (pagination, ordering, behavior on unknown categories), which is minor for this complexity.
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% and the single optional parameter already documents allowed example values and the omit-behavior. The description adds only the phrase "within a specific category", which restates rather than extends the schema, so baseline 3 applies.
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 names a specific verb and resource ("List all topics") and the scope ("within a specific category"), plus the fields returned (titles, slugs, summaries). It does not explicitly contrast itself with siblings like list_categories or search_hig, so the agent must infer the boundary from the word "topics".
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 only conditional behavior (omitting the category lists everything) lives in the schema, not the description. There is no guidance on when to reach for this versus list_categories or search_hig, so alternative selection is left entirely to inference.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.