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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the tool's safety and open-world nature are covered. The description adds that it returns 'candidate search suggestions', but does not elaborate on specific behaviors such as response format or limitations. This adds some but not rich context, aligning with baseline given annotations.

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 a single, compact sentence that both defines the tool and differentiates it from alternatives. No wasted words, and the core information is front-loaded.

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 a simple single-parameter tool, an output schema exists, and annotations cover read-only/open-world, the description is complete enough. It clearly states the purpose, usage, and exclusions. It does not address potential response times or error conditions, but these are not necessary for a tool of this simple nature and the presence of output schema reduces that need.

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% and the parameter description explicitly instructs what to pass (keyword or phrase being typed) and what not to pass (links, IDs, tokens). The description reinforces the schema, but also clarifies the intended input type (being typed) beyond the generic 'search term'. This adds practical guidance, slightly above baseline.

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 retrieves candidate search suggestions based on the search term, with the explicit purpose 'to complete search terms'. It distinguishes itself from xhs_search_notes and xhs_search_products by naming them as alternatives for actual searches, making it clear what this tool does not do.

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 explicitly covers when to use the tool (for completing search terms) and when not to use it: when the user needs to actually search notes or products, directing to xhs_search_notes or xhs_search_products. This provides clear context and alternative tools, leaving no ambiguity.

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