find_cheapest_region

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

No annotations are provided, so the description carries the full burden. It discloses that pricing is queried concurrently, results are sorted cheapest first, and a delta is calculated. It also notes that the region field in the spec is overridden. However, it does not mention idempotency, rate limits, or caching behavior (though cache_stats sibling suggests caching exists).

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 moderately sized, starting with a clear title line, then a brief explanation, followed by an Args section with bullet points. It is front-loaded with the main purpose. A few words could be trimmed, but overall it is efficient and well-structured.

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?

Although an output schema exists (context signal), the description mentions only that results are sorted cheapeast first with a price delta. It lacks details about the output structure, formats, or edge cases. Given the complexity of nested input and 0% schema coverage, the description could be more complete about caching and performance implications.

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 0%, but the description explains each parameter: spec is a PricingSpec dict (same as get_price) with region overridden; regions can be omitted, a list, or ['all'] with speed implications; baseline_region is optional for delta. The spec parameter is not detailed but references get_price, which is acceptable.

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 clearly states the tool's purpose: 'Find the cheapest region for any cloud service.' It specifies the verb 'find' and the resource 'cheapest region', and explains concurrent querying and sorting behavior. The purpose is distinct from siblings like get_price, compare_prices, and find_available_regions.

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 provides usage guidance: 'Omit for major regions (faster). Pass ["all"] to search every available region' and mentions baseline_region for delta comparison. It implies when to use each parameter variant, but does not explicitly state when not to use this tool or provide alternatives among siblings.

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