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

The readOnlyHint annotation already establishes the safety profile, and the description adds useful behavior beyond that: results are newest first, default page size is 20, and the filters are described. It stops short of describing the exact response shape, but with no output schema and annotations covering safety, this is still strong context.

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 definition is front-loaded with purpose, then usage, then filters and pagination, and every sentence contributes. The opening sentence is long and slightly winding, but overall it is efficient and informative.

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 read-only listing tool with ten optional filters, high schema coverage, and readOnlyHint annotations, the description covers purpose, usage, filtering, ordering, and pagination. An agent has enough information to select and call it correctly without additional context.

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 already high at 90%, so the schema carries most parameter detail. The description still adds meaningful semantics, notably that ASINs can be child or parent with no need to know which, and that text search covers description or type.

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 ('seller's EVENTS — the dated notes Nova draws on the charts') and immediately clarifies what counts as an event with concrete examples. It also distinguishes this listing tool from the sibling create_event by explaining that it is used to read existing events and check whether something is already logged.

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 explicit when-to-use guidance: read events when explaining a movement to see what changed around that date, and check this list before calling create_event to avoid duplicate logging. The alternatives and the condition that selects them are named directly.

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