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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description still adds genuine behavior not in the structured fields: result ordering ('Newest first') and data provenance ('at the order's prices'), i.e. prices come from the PO rather than the receipt. It omits volume/pagination limits, which keeps it from a 5.

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?

A single front-loaded sentence of four clauses, zero filler; ordering is stated last for emphasis. It is lean to the point of being fragmentary — a leading verb such as 'List' would make the operation unambiguous at no length cost.

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 one optional param, no output schema, and rich safety annotations, the description does most of the remaining work by telling the agent what each row contains (order, date, prices) and how it is sorted. Only the aggregation scope (all receipts vs. unbilled only) and result size are unstated.

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?

There is one optional parameter with 100% schema description coverage, so the schema already explains po_id fully. The phrase 'against which order' loosely maps to that filter but adds no syntax, default behavior, or what happens when omitted (presumably all receipts). 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?

The description states the resource and its content precisely — receipts with their linked order, arrival date, and order pricing — plus result ordering ('Newest first'). It doesn't use an explicit list/read verb or name the write-side sibling (p2p_receive_goods), but an agent can distinguish this as the goods-receipt reading tool from the four content clauses alone.

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?

Usage is only implied: 'What arrived, against which order, when' suggests reviewing received goods. There is no statement of when to prefer it over p2p_unbilled_receipts, p2p_po, or p2p_receive_goods, and no exclusions or prerequisites.

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