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

Annotations already cover readOnly/destructive/openWorld, so the description's added value is the returned field set (quantity, unit, weeks remaining, reorder guideline, on-hand value) and the inventory-plan prerequisite. Error behavior and what happens for a missing/nonexistent id are not addressed.

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 compact fragments, front-loaded with the resource and id lookup. The parenthetical field list is dense but earns its place by substituting for a missing output 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, listing the returned fields is exactly what the description should supply, and the prerequisite note is useful. Only the ambiguity of the plan prerequisite and absence of error semantics keep it from a 5.

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?

Only one parameter and schema coverage is 100%, with the schema itself stating 'Inventory row id.' The description's 'by id' adds nothing beyond that, so baseline 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?

States a specific verb and resource ('One raw-material stock row by id') and enumerates the returned fields, which clearly separates it from recipal_list_inventories. It does not explicitly name the list sibling as the alternative, so a 5 is not warranted.

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?

'Needs an inventory plan' signals a prerequisite, but the phrasing is terse and ambiguous - it is unclear whether the plan feature gates the call or is merely context. No alternatives or when-not-to-use conditions are given.

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