Get promotions

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuinely useful behavior beyond that: the result shape at each drill-down level ("sections ... with a few products and promotions each") and the fact that returned products carry add_to_cart ids. It does not mention result size limits, pagination, or how current the "this week" data is.

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 tight sentences, front-loaded with the core purpose, followed by each invocation mode in the order an agent would use them. No filler and no repetition of the schema.

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 no output schema, the description carries the burden of describing returns, and it does so at a high level for all three modes plus the product id handoff to add_to_cart. Slightly incomplete on how many sections/products come back and whether results are exhaustive per section.

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 coverage is 100%, so baseline is 3, but the description goes further by explaining the dependency chain: the overview yields section titles and promotionIds that feed the next call, and omitting both yields the overview. That relational meaning is not in the schema.

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 and resource with scope: "List what is on promotion at Picnic this week." It then distinguishes three distinct result modes (overview, section, single promotion), which makes clear this is a promotions browser rather than a product search, separate from siblings like search_products or get_product.

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?

Gives explicit per-mode usage: no input for the section overview, a section title for all products in it, a promotionId for the products of one promotion. It also hints at the downstream workflow ("Products have ids for add_to_cart"). It stops short of naming alternatives or exclusions, e.g. when to prefer search_products over browsing promotions.

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