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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the agent knows this is a safe read operation. The description adds useful behavioral context: it returns a checklist and a preview, covers specific Visa/Mastercard reason codes, and explicitly notes it is not legal advice. It also clarifies the full letter is a separate paid product, which prevents the agent from promising more than the tool delivers.

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 a single paragraph that front-loads the core function, then lists covered reason codes, then clarifies the paid product boundary and legal disclaimer. It is reasonably concise, though the reason-code enumeration adds length. Every sentence earns its place, and the structure is logical.

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 checklist tool with 100% schema coverage and no output schema, the description is complete enough: it states inputs, outputs, coverage, and limitations. It could mention that the output is a preview rather than a full letter, but it already does. The only minor gap is not describing the exact format of the checklist or preview, but that is not essential for an agent to invoke the tool correctly.

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%, so the schema already documents all 7 parameters. The description adds context about what the category parameter maps to (Visa/Mastercard reason codes) and what the output will use (tracking numbers, prior-order signals, refund records), but it does not add much beyond the schema's own detailed enum descriptions. Baseline 3 is appropriate.

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 verb ('return the evidence checklist') and resource ('chargeback/dispute reason code category'), and explicitly lists the covered reason codes and categories. It clearly distinguishes itself from the separate $39 product that produces the full formatted letter, so an agent can tell what this tool does and does not do.

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 when to use this tool: when a chargeback/dispute reason code category and order details are available, and the user needs the evidence checklist and a preview of the response letter. It also explicitly says the full formatted letter is a separate paid product, which is a useful exclusion. It does not explicitly name sibling tools or state when not to use it, but the context is clear enough.

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