list_icons

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

With no annotations, the description carries the transparency burden and reveals important behavioral traits: 'ds-brand' maps to ~70 authoritative icons, 'lucide' has ~1,500 with only ~80 having hand-authored metadata, and 'all' unions both. This helps set expectations about data richness, though it doesn't cover pagination or result ordering.

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 lead sentence, then a terse breakdown of each source value. Every sentence adds value, and the use of backticks for parameter values improves readability.

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 list tool with four optional parameters, the description covers the key differentiator (sources) and acknowledges metadata limitations. However, it could be more complete by mentioning the return format or explicitly referencing search_icons for filtered lookups, which would aid selection between sibling tools.

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 coverage is 100%, so a baseline of 3 applies. The description adds significant meaning to the `source` parameter by explaining the enum values, including exact counts and the metadata caveat for lucide. It goes beyond the schema's terse 'Icon source' description.

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 function ('List available icons') and provides specific details about the three source options, distinguishing it from sibling tools like search_icons and list_components. The scope (sources and counts) is unambiguous.

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 gives clear context on when to use each source variant (ds-brand, lucide, all), but does not explicitly contrast with the sibling search_icons tool. It implies usage through source semantics but lacks an explicit 'when to use this vs search_icons' note.

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