Open a packing list

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

With no annotations, the description carries the behavioral burden. It does disclose the free-tier slot limit and the return value, but it does not explicitly say this is a creating/mutating operation, what happens when the limit is reached, or whether errors occur for duplicate open lists. The slot-freeing note is helpful but incomplete.

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 concise sentences with no filler. The core purpose is front-loaded, and the free-tier constraint is stated in one clear follow-up sentence.

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?

The description covers purpose, return value, and a key operational limit, but for a create-like tool with 7 parameters and no output schema it lacks explicit guidance on when to use it versus siblings, how the duplicate_ok parameter interacts with the limit, and what the response includes beyond the PL number.

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 86%, so the schema already documents most parameters. The description adds context by tying 'where it ships to' to ship_to and 'the date' to date, but it adds no semantics for note, duplicate_ok, or reference_kind beyond what the schema provides.

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 states a specific verb and resource: 'Open a packing list against an order and return its PL-YYYY-NNNN number.' It also lists the key data involved (order reference, consignee, ship-to, date), which clearly distinguishes it from listing, showing, or deleting packing lists.

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 usage context is implied: use this when you need to open a new packing list against an order. It also gives a practical constraint ('Free tier: 3 open at once; shipping or cancelling frees a slot'), but it never names alternatives or states when not to use this tool versus the sibling packing tools.

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