Compare GPU prices

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

Annotations already convey read-only, idempotent, non-destructive behavior. The description adds meaningful behavioral details beyond that: results are sorted cheapest-first, prices are current, and models not publishing are listed without a price. No contradiction with annotations.

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 sentences with no filler: the first states the core purpose and ordering, the second explains the parameter default, and the third covers an edge case. All sentences earn their 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 simple read-only comparison tool with no output schema, the description covers purpose, ordering, default behavior, and an edge case. It could add return-format expectations or explicit sibling routing, but nothing critical 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 input schema already covers `models` as a subset defaulting to all, so baseline is 3. The description adds concrete model IDs (A100, H100, H200, B200) and clarifies the omission behavior, providing useful supplementary meaning beyond the schema.

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 ('compare'), a clear resource ('current rental prices per GPU-hour across models'), and distinct output behavior ('cheapest first, with each model's multiple of the cheapest one'). This makes it immediately distinguishable from siblings like get_gpu_price, get_gpu_price_history, and get_gpu_market_summary.

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 clear usage context: use this tool to compare current prices across models, and omit `models` to compare every model in the index. It does not explicitly mention alternatives or when not to use it, but the core use case is well implied.

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