Update Coupon

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

With no annotations, the description carries the full burden. It usefully discloses partial-update semantics ('Only specified fields are changed') and value encodings (status 1/0, date format), but says nothing about permissions/auth requirements, reversibility, validation failures, or what happens to unspecified fields beyond omission.

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 tight sentences: the action plus the field list first, the partial-update guarantee second. No filler, 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?

Given an output schema exists, return values need not be explained, and the field-level semantics are well covered for a mutation tool. The remaining gap is behavioral context (auth/permissions, error behavior) for a write operation with no annotations.

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 0%, so the description must compensate, and it largely does: it gives meaning and format for status (1/0), date_end (YYYY-MM-DD), discount, total-use limit (uses_total), and name. It does not explicitly flag coupon_id as the required identifier, leaving one 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?

The description uses a specific verb ('Update') and resource ('a coupon') and enumerates exactly which fields can be changed (status, discount, date_end, total-use limit, name). This clearly distinguishes it from create_coupon and get_coupons, though it does not name those siblings explicitly.

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: it is for modifying an existing coupon identified by coupon_id, and the phrase 'Only specified fields are changed' hints at a partial-update/PATCH pattern. However, there is no explicit guidance on when to use this versus create_coupon, nor any stated prerequisites or conditions.

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