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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds that results are 'predictive-search' suggestions spanning three types, but it does not disclose rate limits, that suggestions are non-authoritative, or any other behavior beyond the annotations and schema.

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 tight sentences: the purpose is front-loaded and the routing hint follows. Every clause earns its place with no restatement of the parameter list or redundant detail.

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?

With an output schema present, the description needn't explain return values, and annotations cover safety, so the definition covers purpose and routing adequately. It is marginally thin on guidance for choosing suggestion types and limits, but the schema fills those gaps.

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%, documenting q, limit (default 10, max 20), and types with allowed values. The description's mention of products, collections, and query phrases maps to the types enum but adds no syntax or format detail beyond the schema. Baseline 3 is appropriate.

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?

States a specific verb ('Fetch') and resource ('SKIMS predictive-search suggestions') with clear scope covering products, collections, and query phrases. It explicitly names the sibling tools skims_products and skims_collections, so an agent can distinguish this typeahead-style tool from record-browsing tools without opening schemas.

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 second sentence routes the agent: use skims_products to browse product records or skims_collections for collection listings, implying suggest is for predictive/autocomplete queries. It stops short of stating an explicit when-not condition (e.g., that suggestions are low-confidence prefixes rather than real records), but context is clear.

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