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

Annotations already declare a safe read (readOnlyHint, idempotentHint, destructiveHint=false), so the safety bar is low. The description still adds genuine behavioral context: it is informational only, never adjudicates a claim, ranks results by strength, and folds in payment-remedy layers (section 75, chargeback, PayPal, BNPL) and onward guidance.

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?

It is a single dense sentence, but it is front-loaded with the resource and output contents and every clause earns its place (ranking, date, statute names, payment layers, next steps, disclaimer). No filler or restatement of the name.

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?

With 13 parameters, 6 required, and no output schema, the description carries the return-value burden and does so: it explains the ranked-rights list, the last-day date, the cited statutes, and payment-derived options. Only minor gaps remain around required inputs and result limits.

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 92%, so the schema already carries the parameter documentation and the baseline is 3. The description adds some conceptual meaning to 'paid' (what section 75/chargeback/BNPL add) but does not clarify formats or the roles of parameters like nation or exceptions beyond what the schema states.

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 and resource (UK consumer rights applying to a purchase) and enumerates the exact output: rights ranked strongest first, each with its last day as a date and the governing law, plus payment-method extras and next steps. This is precise enough to distinguish it from every sibling (all shopping/deal tools) without opening the schema.

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 name and by the disclaimer 'Legal information, not legal advice: it never decides a claim', which sets expectations about what the tool will and won't do. However, there is no explicit when-to-use statement, no prerequisites (e.g. that ordered_on/price/paid must be supplied), and no named alternatives. Adequate but with clear gaps.

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