Create a promotion

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

Annotations already declare destructiveHint=true, idempotentHint=false, readOnlyHint=false, and openWorldHint=true, so the safety profile is covered structurally. The description's one genuine contribution beyond that is the rate limit (100 requests / 10 seconds per shop), which is real behavioral context, but it says nothing about required permissions, side effects, or the create semantics of the union payload.

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?

It is short, but the rate-limit callout is placed ahead of the single purpose sentence, which front-loads an operational detail over the tool's function. Nothing is padded, yet nothing is front-loaded usefully either.

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?

This is a destructive write with a complex five-variant union payload (MEMBERSHIPS_MULTI/SINGLE, SHOP_MULTI/SINGLE) and no output schema. The description does not explain the variant selection, the required code/discount combinations, or the meaning of the confirm gate, leaving substantial gaps for a tool of this complexity.

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 account, confirm, payload, and payload_file, including the oneOf variants and the mutual-exclusion rules. The description adds no parameter meaning at all, so the baseline 3 for a fully documented schema applies.

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 says only "Creates a promotion," which restates the name and title without adding a verb-plus-resource distinction beyond them. It gives no hint of the promotion variants (membership vs shop, single vs multi code) that the schema actually requires, nor any differentiation from siblings like update_promotion or list_promotions.

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 mention of prerequisites, and no routing to alternatives such as update_promotion. The rate-limit note is operational, not usage guidance, so an agent gets nothing about when this tool is the right choice.

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