Shopping basket

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, open world), so the description's real contribution is the fuzzy name-resolution behavior: names map to the top search match and ids should be passed for exactness. That is a genuine behavioral caveat an agent would otherwise miss, though it says nothing about what happens when no single shop stocks everything.

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?

Two tight sentences, front-loaded with the core behavior and the caveat placed second. The parenthetical reference to items[].name is compact, though it points at a response field with no output schema to anchor it.

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 does sketch the return shape ('best single shop' plus 'split-cart total'), which is the minimum needed. It omits the fallback behavior when no single shop covers the list and leaves the min_score threshold unexplained for a tool with five parameters.

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 80%, so the baseline applies. The description meaningfully clarifies the `items` parameter (names resolve loosely; verify against the returned items[].name), but the undocumented `min_score` parameter — a scoring threshold with no schema description — is not addressed at all.

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 computation over a specific resource: cheapest single shop covering a whole list plus the split-cart total. That is clearly distinct from single-product siblings like tb_cheapest and tb_compare, though it never names those siblings explicitly.

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?

The phrase 'whole shopping list' implies the multi-item use case, distinguishing it in spirit from single-item price tools, but there is no explicit when-to-use/when-not or named alternative such as tb_cheapest or tb_shop. The agent must infer the routing decision.

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