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

Annotations already declare readOnlyHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is covered; the description adds genuinely non-obvious behavior — the catalog contains only published fixed-price offers, and any brief returns the identical product with a brief_relevance note. It says nothing about account scoping or result size/pagination, which is the remaining gap.

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?

Three short sentences with the catalog/format distinction front-loaded and no filler. The final sentence is slightly ambiguous about whether wholesale_feed_version is an input here or a value to pass onward, which costs a little clarity.

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 five-parameter tool with nested brand/account objects, an unexplained buying_mode enum, and no output schema, the description covers the catalog's nature and the brief behavior but leaves account/brand scoping and the buying-mode paths undocumented. An agent could call it, but not confidently tailor account or mode.

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 0% across five parameters, so the description must carry the burden. It explains only that brief does not filter, and it refers to 'wholesale_feed_version' while the schema property is 'if_wholesale_feed_version', leaving brand, account, and the brief/wholesale/refine buying_mode enum entirely undefined.

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 opening sentence establishes that this returns the same catalog as list_products but in the AdCP 3.1 shape, which lets an agent distinguish it from that sibling on format rather than resource. It never states plainly that it retrieves a product catalog, so the verb+resource is inferred by reference to a sibling rather than named directly.

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 a clear selection rule against list_products (use this for the AdCP 3.1 shape) and a downstream workflow pointer ('use wholesale_feed_version with create_media_buy or buy_products'). It also warns that brief-based filtering is a no-op here, which prevents a wasted refinement attempt. No explicit when-not guidance beyond that.

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