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

The annotations already establish readOnly, idempotent, non-destructive, and closed-world behavior. The description adds valuable nuance beyond those annotations: dates are independent of lifetime referral codes, and the tool does not claim campaigns are active or that a user qualifies. This clarifies semantic boundaries the annotations cannot express.

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, each carrying distinct meaning: what is listed, how dates behave, and what the listing does not assert. It is front-loaded and contains no filler, repetition, or unnecessary 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?

Given the presence of an output schema, annotations covering safety/idempotency, and only three optional parameters, the description covers the semantic essentials. It could add more context about pagination or brand filtering, but those are at least partially encoded in the input schema. The main gap is already scored under parameter semantics.

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 only 33% – only 'brand' has descriptive text, while 'limit' and 'offset' rely on numeric constraints. The description adds no parameter-level meaning, leaving the undocumented parameters underspecified for a tool with low schema coverage. It should have compensated but does not.

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 names a specific verb and resource: 'List source-backed campaign announcements, official source links and published event windows.' It is distinctly about campaigns and explicitly clarifies a non-claim about activity or user qualification, which helps differentiate it from code/brand tools. It does not explicitly name sibling alternatives, but the purpose itself is unambiguous.

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 implies usage context by stating that dates are independent of referral codes and that it does not assert campaign activity or user eligibility. However, it never explicitly states when to prefer this tool over sibling tools like search_codes or get_code, nor does it state exclusions or when-not-to-use conditions.

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