List Rental Pricing Tiers

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

Beyond the annotations' readOnlyHint and idempotentHint, the description adds a critical behavioral caveat: the output is a raw catalog dump that may include non-purchasable rows and is not authoritative. This warns the agent not to treat the results as actionable inventory, which is exactly the kind of behavioral nuance annotations cannot convey.

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?

Three compact sentences front-load the purpose, then provide the essential caveat, and finally route to alternatives. There is no filler or repetition; every sentence earns its place.

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 parameterless, read-only catalog tool with no output schema, the description covers everything an agent needs: what the tool returns, how reliable that data is, what to do before creating a rental, and which sibling tool to use for different pricing needs.

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 has zero parameters, so the baseline is 4. The description adds meaning by explaining what the returned catalog contains (local SIM inventory, durations, prices), even though there is no input schema to elaborate on.

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 opens with a specific verb and resource: 'List all active rental pricing tiers,' and clarifies the content as local SIM inventory, durations, and prices for the Full Access tier. It also differentiates itself from the sibling tools by explicitly naming rentals_price and rentals_available as alternatives, making the tool's scope unmistakable.

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 gives explicit when-not-to-trust guidance: 'This is a raw catalog dump and may list rows that are not purchasable today, so confirm against rentals_available... before creating a rental.' It also directs agents to rentals_price for platform-tier per-country pricing, leaving no ambiguity about which sibling to use in which scenario.

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