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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description adds genuinely non-obvious semantics: existing subscribers retain their discount, which prevents an agent from assuming a blanket revocation. It stops short of stating reversibility or permission requirements.

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?

Short and front-loaded, but the second sentence largely restates the first ('Stop a discount code working' / 'Stops one discount code working for new purchases') before adding the one new fact. That duplication costs a point against strict conciseness.

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 simple two-parameter mutation with no output schema and annotations covering destructiveness, the description supplies the key behavioral nuance an agent needs. Missing only reversibility/auth details, which is a minor gap at this complexity level.

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% with only two parameters, so the schema already documents 'id' and 'business' fully. The description mentions 'one discount code' (implying a single id) but adds no format or scoping detail beyond the schema. 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?

States a specific verb and resource ('Stop a discount code working') and clarifies what 'archive' actually means operationally. It is distinguishable from sibling read tools like discounts_show and create tools, though it never names an alternative for reversing the action.

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 by the effect ('for new purchases') rather than stated as guidance. It never says when to use archive versus leaving a code alone, nor whether it can be undone, and no sibling alternative is offered. Minimum viable routing information only.

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