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

With no annotations, the description carries the full burden. It discloses that renaming keeps existing redemption rows, that it requires operator proof, and how clear flags work. However, it lacks details on side effects of other fields, validation behavior, or error conditions.

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 with four sentences, each adding value. It front-loads the core purpose and then covers specific behaviors. No unnecessary words.

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 complexity (10 params, no schema descriptions), the description covers essential behavior but omits details on the output (though output schema exists) and error handling. It is adequate but not exhaustive.

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 0%, but the description only explains two parameters (clear_uses_per_patron, clear_total_uses). The rest (e.g., name, discount_percent, valid_from) are not described. The general note 'Pass only the fields you want to change' is insufficient for the 10 parameters.

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 'Patch a coupon's editable fields' which clearly identifies the tool as an update operation on coupon fields, distinguishing it from siblings like excalibur_mint_coupon (create) and excalibur_delete_coupon (delete).

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?

It instructs to pass only fields to change and explains how to set values to unlimited using clear flags. It also notes that renaming the code is allowed and that the tool is restricted to operators with proof. However, it does not explicitly state when not to use it or mention alternatives.

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