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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false, so 'Read-only; changes nothing' largely repeats structured data. The one genuine addition is the money-unit convention ('integer minor units (cents)'), which matters because there is no output schema to document returned amounts, but scope/pagination behavior is still undisclosed.

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 front-loaded fragments with no filler, and the read-only constraint is stated immediately after the resource. It is terse to the point of under-specification, which is a completeness problem rather than a structure problem.

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?

No output schema exists, so the description should carry the return-shape burden, yet it never explains what a promotion record contains, whether scheduled and checkout-pending entries are included, or how results are ordered. The money-unit note is a useful partial compensation, but an agent still lacks enough to interpret the response confidently.

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 there is nothing for the description to disambiguate; the baseline for a no-param tool is 4. No misleading parameter claims are present.

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 is a noun phrase ('Sales and discounts running') with no verb, so it never explicitly says it lists/returns promotions state. The sibling set (promotions_edit, promotions_delete, promotions_set_active) makes the read-only nature inferable, and 'Read-only; changes nothing' helps position it as the query counterpart, but the core purpose is left implied rather than stated.

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?

There is no when-to-use guidance, no conditions, and no mention of alternatives such as discounts_catalog_sale or promotions_set_active. The read-only phrase weakly implies 'use this to inspect rather than modify', but the agent must infer all routing decisions.

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