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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, covering safety and idempotency. The description adds the return format and lists example libraries, which is helpful beyond annotations. Could be improved by mentioning sorting or pagination, but overall transparent.

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?

Two concise sentences, front-loaded with the primary verb and resource. No unnecessary words; every sentence provides essential information. Efficient structure.

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 search tool with 3 parameters and an output schema (not shown), the description fully covers the tool's behavior. The return format is detailed, and the scope is clear. No gaps given the tool's simplicity.

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% with descriptions for all 3 parameters. The description adds value by explaining the return format and giving concrete examples (e.g., 'mdi:home'), which helps agents understand parameter usage beyond schema types.

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?

Description explicitly states 'Search for icons by keyword across 100+ icon libraries', clearly identifying the action (search), resource (icons), and scope (multiple libraries). The return format is specified, and the tool's function is distinct from siblings like get_collection_icons and list_collections.

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 usage for keyword-based searching across libraries but does not explicitly state when to avoid using it (e.g., when a specific collection is desired). However, the sibling tool names provide context that aids in differentiation, making the usage clear enough for an agent.

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