mhlb_apply_coupon

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

Annotations already indicate a write (readOnlyHint=false) and open world. The description adds significant context by warning that the write is UNVERIFIED and derived from a compiled API client, and instructs to inspect the dry-run preview before confirming. This is a valuable disclosure beyond annotations, though it doesn't describe exact side effects or return structure.

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?

The description is concise: one sentence states the action, and a second sentence provides a critical caution. The main purpose is front-loaded, and no unnecessary words. It is appropriately sized for the tool's complexity.

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 the write nature, the presence of a confirm parameter, and no output schema, the description, combined with the schema, gives an agent enough to safely invoke the tool. The warning about unverified behavior and the instruction to inspect the preview cover important operational details. Return format is not essential 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 description coverage is 100%. The schema already explains both parameters (code and confirm), including the preview behavior. The description adds minimal parameter-specific meaning beyond the note about dry-run preview, which is already in the confirm schema. So it does not substantially exceed the schema baseline.

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 action ('Apply a coupon code to the account') with a clear verb and resource. It distinguishes from siblings like mhlb_apply_gift_card (different resource) and mhlb_get_coupon/remove_coupon (different actions), so an agent can correctly select it.

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 description implies usage when a coupon must be applied, but does not explicitly mention alternatives or exclusions. It provides a caution about the unverified write but no direct guidance on when to prefer this over mhlb_apply_gift_card or mhlb_remove_coupon. Some context is given, but no exclusions.

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