Get product categories

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

No annotations are provided, so the description carries the full burden. It clearly states this is a read-only retrieval operation, which is inherently safe. However, it does not disclose any behavioral traits such as error handling for invalid category_id, size limits, or response structure. For a simple read operation, this is acceptable but not rich.

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 sentence, front-loaded with the action and resource, and every word contributes meaning. It is concise without losing necessary 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?

For a tool with one optional parameter and no output schema, the description covers the core call logic. It could specify what a subtree looks like or how invalid IDs are handled, but the low complexity and the schema's documentation of the parameter make this sufficiently complete for an agent to invoke the tool correctly.

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% because the property description for category_id explains its meaning and the '0' special case. The tool description adds a subtle point about subtree behavior but does not materially go beyond the schema. This aligns with the baseline 3 for high schema coverage.

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 uses a specific verb ('Retrieve') and names the exact resource ('eBay category tree'), including the optional subtree case. This clearly differentiates it from the sibling tools, which are all about products, cart, or orders—none deal with categories.

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 makes the primary use case explicit: retrieve the full tree by default or a subtree when category_id is provided. It does not explicitly list when not to use it, but since there is no alternative category tool among siblings, this guidance is adequate. A small gap is not mentioning that omitting category_id is equivalent to 0.

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