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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description still adds useful scope context beyond the annotations: prices are denominated in USD, all three tiers are included, and limits/inclusions are returned alongside prices.

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?

One dense sentence that front-loads the resource and then lists the concrete payload (plans, prices, inclusions, limits, cheapest single-event option). No filler or restatement of the title.

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 no parameters and no output schema, the description carries the full burden of describing the return payload, and it does so explicitly (plan tiers, USD prices, inclusions, limits, cheapest option). Nothing an agent needs to invoke it correctly is missing.

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?

The tool takes zero parameters, so the baseline is 4; there is no argument semantics to explain and the description correctly spends no words on inputs.

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 resource (QR Wall plans and one-off add-ons) and enumerates the plan tiers, so an agent immediately knows what comes back. It does not, however, differentiate itself from the sibling 'compare', which an agent might reasonably pick when it wants plan-to-plan differences.

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 only implied: the mention of 'the cheapest way to cover a single event' hints at a use case, but there is no explicit when-to-call, when-not-to-call, or routing to siblings such as 'compare' or 'find_use_case'.

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