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

Annotations already cover readOnly/openWorld/non-destructive, so the bar is lower, and the description still adds real value: the concrete returned metrics and the warning that there is no paging, which tells the agent the result set can be unbounded. It does not cover ordering or defaults, but the safety profile is fully handled by annotations.

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 tight sentences with no filler: returned fields first, then filtering, then the paging caveat plus endpoint. Every sentence carries distinct information and the most important constraint is front-loaded.

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?

For a read-only list with no output schema, the description covers what a row contains and the key risk of unpaged results. It stops short of saying what happens when no filters are supplied (full dump?) or how results are ordered, which are the remaining uncertainties for correct invocation.

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 filters are already documented in the schema, including cross-references to sapo_list_locations and sapo_list_inventory_items. The description restates the filter options without adding syntax or format detail, so the 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?

Names the specific resource (stock per item and location) and enumerates the returned fields (on_hand, available, committed, incoming, reserved). That distinguishes it cleanly from siblings like sapo_list_inventory_items, sapo_list_locations, and sapo_set_inventory_level.

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?

Explains the three filtering strategies (item ids, location ids, available min/max) and adds the operational rule to narrow with ids because the upstream API documents no paging. It gives clear usage context but never explicitly states when to prefer a sibling tool or what it is not for.

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