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

Annotations already declare readOnly, idempotent, non-destructive, non-open-world. The description adds genuine context beyond them: the auth prerequisite ('Needs a connected WaitApp account'), the cart-free nature, and the full set of returned facts (fee, distance, ETA, in-area check, open-now status). It does not contradict any annotation.

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?

Four sentences, each contributing: the core return, the cart-free positioning, the output extras, and the auth requirement. The core value is front-loaded. It is slightly dense but wastes little.

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 responsibly enumerates what is returned (fee, distance, ETA, delivery-area check, open-now) and notes the account prerequisite. For a 3-param read tool this is close to complete, missing only guidance on the undocumented restaurantId source.

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 67%: deliveryAddress and savedLocationId are already documented, while restaurantId has no schema description. The description mentions 'one venue' and 'an address or a saved location' but adds no format, id-source, or mutual-exclusivity detail beyond the schema. Baseline 3 is appropriate when the schema carries most of the parameter meaning.

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+resource: returns delivery fee, distance and estimated delivery time from one venue to an address. It explicitly distinguishes itself from draft_delivery_order by noting it works 'with no cart' and returns 'the same one a draft order then shows.' An agent can tell this apart from its order-drafting siblings without opening a schema.

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?

'A quick way to compare venues before building an order' gives clear when-to-use context and implicitly positions it upstream of draft_delivery_order. It also notes it accepts a saved location as an alternative input. It stops short of explicit when-not-to-use exclusions, but the routing intent is clear.

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