DescribeZones

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states what the tool does (querying) without mentioning whether it's a read-only operation, if it requires authentication, rate limits, pagination, error handling, or the format of returned data. For a query tool with zero annotation coverage, this leaves significant behavioral gaps.

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 a single, efficient sentence that directly states the tool's purpose and key parameters. It's front-loaded with essential information and contains no redundant or verbose language, making it easy to parse quickly.

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?

Given the tool's moderate complexity (5 parameters, 1 required) and rich schema documentation (100% coverage), the description is minimally adequate. However, with no annotations and no output schema, it lacks crucial behavioral and output details. The description alone doesn't fully compensate for these gaps, leaving the agent with incomplete context for proper tool invocation.

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 100%, meaning all parameters are well-documented in the schema itself. The description adds minimal value beyond the schema by listing example parameters ('地域ID、计费方式等参数' - region ID, billing method, etc.), but doesn't provide additional context like parameter interactions or usage examples. With high schema coverage, the baseline score of 3 is appropriate.

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: '查询可用区信息列表' (query available zone information list) based on parameters like region ID and billing method. It specifies the verb (query) and resource (available zone information), making the purpose unambiguous. However, it doesn't explicitly differentiate from sibling tools like DescribeRegions or DescribeAvailableResource, which likely provide related but different information.

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 no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like DescribeRegions (which lists regions) or DescribeAvailableResource (which might list resources within zones), nor does it specify prerequisites, use cases, or exclusions. The agent must infer usage from the tool name and parameters alone.

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