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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint), so the description only needs to add what they don't say. It does: the result set is limited to currently published affiliates with retired entries filtered out, and it warns that a catalog row does not imply plan access or an open offer — meaningful semantic context beyond the annotations. It stops short of noting ordering, freshness, or result size.

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 sentences, no filler. The concrete behavior (what is listed, what is excluded) is front-loaded, and the cautionary note follows only after the core purpose is established.

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?

With zero parameters, an output schema present, and annotations covering safety and idempotency, the description carries little remaining burden — and it meets it by defining scope and the correct interpretation of results. Minor omissions (ordering, pagination, or volume of affiliates) are the only reason this isn't a 5.

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?

The tool takes zero parameters, so the baseline is 4 by rule; there are no parameter semantics for the description to clarify. Nothing in the description misrepresents the (empty) input contract, and it helpfully clarifies the implicit output scope instead.

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?

States a specific verb ('List') and resource ('affiliate IDs and names') with an explicit scope qualifier: currently published, retired ones excluded. An agent can separate this from sibling catalog tools like list_sports or list_markets without opening any schema, and it even discloses which fields are returned.

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 gives an interpretation caveat ('Do not use a catalog row as proof of plan access or an open offer'), which is useful guidance about the meaning of results. However, it never says when to prefer this tool over the sibling list_* tools, nor does it name any alternative or exclusion condition for tool selection. Usage is therefore implied rather than directed.

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