uber_eats_update_cart_quantity

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

No annotations are provided, so description carries full burden. It discloses the mutation nature (changing quantity), describes matching behavior (UUID preferred, partial name match fallback), and flags a grocery_store caveat for update failures. However, it doesn't mention edge cases like zero/negative quantity behavior, item-not-found errors, or whether price recalculates—though some of this may be covered by the output schema.

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?

Well-structured: opening one-liner, a 'Best/Otherwise' pairing for usage, a conditional tip, then a compact Args list. Every sentence earns its place. Slightly verbose but the info density justifies it—no fluff.

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 4 params with 0% schema coverage and an output schema present (which likely documents return values), the description covers the important gaps: the identification strategy, fallback matching, and the grocery performance caveat. An output schema being present lowers the bar for describing returns. A strong case for mentioning max quantity limits or confirmation of success is minor next to what's covered.

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 0%, so the description must compensate, and it does. Each of the 4 params is explained beyond the schema: quantity ('1 or more'), item_name ('line title to match if UUID not provided'), shopping_cart_item_uuid ('from view_cart items[] preferred'), and grocery_store ('hint for large markets / grocery carts'). This adds real semantic value the bare schema lacks.

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?

Clear verb+resource ('Change the quantity of a line already in the cart'), explicitly states it uses the same API as the site, and differentiates from siblings (add_to_cart, remove_from_cart, view_cart). The distinction from other cart operations 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?

Provides explicit guidance on best practice (pass shopping_cart_item_uuid from view_cart) and a fallback (match by item_name, partial match ok). Also gives a conditional hint for grocery stores. It doesn't explicitly name 'when not to use,' but the positive usage context is strong.

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