list_fonts

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds platform scope (macOS CoreText) and the language-support check, but does not disclose the exact return shape or edge-case behavior.

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 concise, front-loaded sentence that names the action, scope, and purpose without filler. Every element earns its place.

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, one-parameter enumeration tool with strong annotations, the description is largely sufficient: it states the platform, what is listed, and the per-language check. It stops just short of describing the exact result shape, which is a minor gap given there is no output schema.

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 single `language` parameter has no schema description (0% coverage). The tool description clarifies that language is the target language for glyph support, but it does not specify accepted formats or values beyond the default 'ko', so it only partially compensates 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 concrete action ('enumerate') and a specific resource ('macOS CoreText installed fonts'), then adds a distinct purpose: checking sample glyph support for a target language. This clearly separates it from subtitle/overlay sibling tools like list_subtitles and status.

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?

No explicit when-to-use or alternative tool is given. The description implies it is relevant when font/glyph support for a language matters, e.g., before configuring subtitle style, but leaves that inference to the agent.

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