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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the useful scoping notion of 'saved' sellers, but it does not disclose return shape, ordering, pagination, or any other behavior beyond what annotations and schema already imply.

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 first states the action and resource, and the second provides realistic user phrasing. There is no filler or redundant restatement of the schema.

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 simple read-only list tool with only three scalar parameters, full schema coverage, and read-only annotations, the description is largely sufficient. A mention of what the returned list contains could push it higher, but the examples and schema make the expected behavior clear enough.

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 schema already documents brand, marketplace_id, and seller_contains. The description does not add further parameter-level meaning beyond framing the brand as the main lookup key.

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 opens with a specific verb and resource: 'List the saved authorized sellers for a brand.' This clearly distinguishes it from sibling authorized_seller_set (which modifies the list) and unauthorized_sellers (which addresses a different concept).

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 provides explicit natural-language trigger examples: 'who are my authorized sellers for X', 'show my approved resellers', and 'what's my whitelist for this brand.' It clearly indicates when to use the tool, though it does not explicitly mention when not to use it or point to the setter alternative.

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