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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds value beyond them by disclosing the result cap (“up to 100 stock items”) and the shape of each item, plus a scope boundary against price data.

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 short sentences, front-loaded with the triggering condition, then the return shape, then the exclusion. Every sentence earns its place and nothing is repeated from the schema or annotations.

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 an output schema present and full schema coverage, the description does not need to explain return values or parameter formats. It covers the trigger, the result cap and one boundary case; the only minor gap is the lack of explicit guidance toward the sibling tool for modifying stock.

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 all four parameters (limit, search, salonId, lowStockOnly) are already documented in the schema. The description only loosely echoes two of them (“up to 100” and the low-stock flag) and adds no new filtering semantics, so the baseline of 3 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 pairs a concrete intent (“how much of a product is left in the salon's stock”) with the resource it reads, and states the returned fields (unit, quantity, minimum, low-stock flag). It is clearly a read/list tool and implicitly contrasts with the write-side sibling set_inventory_quantity, though it never names that sibling.

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?

“Use this when someone asks how much of a product is left... or what is running low” gives an explicit trigger condition, and “Not for retail prices” gives one exclusion. It stops short of naming the alternative tool to use for updating stock or for price data, so the routing guidance is helpful but not fully closed.

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