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

Goes beyond the annotations (readOnly, idempotent, non-destructive) by explaining a real behavioral quirk: shops do not track quantities, so quantity is always null. It also discloses that quote_order re-verifies at order time, which matters for an agent deciding how much to trust the result.

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 short sentences, front-loaded with the outcome definition, then the null-quantity caveat and the ordering cross-reference. No filler.

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, no-output-schema availability check, the description covers what is returned conceptually (available/sold out, null quantity) and when results may change. Only return-format/pagination-style details are absent, which is minor here.

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 only 50%, and the description adds no meaning about the two parameters. It never mentions product_ids (including the max of 50 items) or the shop parameter's conditional requirement, so it does not compensate for the coverage gap.

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 check ('Whether products can be ordered now') with the two possible outcomes (available or sold out), which is more concrete than the title. It does not explicitly differentiate itself from siblings like get_product or search_products, but the verb+resource are unambiguous.

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 implied rather than stated; the closest thing to guidance is the note that 'quote_order checks again when ordering', which hints this check is not required before ordering. There is no explicit when-to-use/when-not-to-use framing or named alternative for availability checks.

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