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

Annotations already declare readOnlyHint=true and openWorldHint=true. The description adds the useful downstream behavior that a matched username feeds into depop_shop, but it does not disclose pagination, result format, rate limits, or other operational traits beyond what the annotations provide.

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, front-loaded sentence with no wasted text. It communicates the core action and the downstream integration in one efficient statement.

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?

The tool has a simple one-parameter schema with full coverage, read-only/open-world annotations, and an output schema. The description provides enough purpose and workflow context for an agent to call it correctly without needing additional return-value or safety details.

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%, so the single 'query' parameter is fully documented in the schema. The description's phrase 'by name or username' mirrors the schema without adding syntax, format, or handling details beyond it, making the baseline 3 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?

The description states a specific verb and resource: 'Find Depop users/sellers by name or username.' It also distinguishes itself from item-search siblings by specifying users/sellers and by noting that a matched result's username feeds into depop_shop.

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?

It gives clear context for use: finding a seller username that then feeds directly into depop_shop. However, it does not explicitly name alternatives such as depop_search or depop_suggest, nor does it state when not to use this tool.

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