zia_list_vpn_credentials

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

Annotations already declare readOnlyHint=true, indicating safe read operation. The description adds the behavioral hint that PSK is never returned, which is useful beyond annotations. However, it does not disclose other behaviors like pagination, result size limits, or error conditions.

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 concise sentence, front-loading the core action and the key PSK omission. However, it is too terse and omits potentially useful context like response format.

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 lack of output schema, the description should explain what the response contains (e.g., fields such as name, id, etc.) but only mentions what is not returned (PSK). It also fails to describe the 'search' parameter, making the tool definition incomplete for an agent to fully understand usage.

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 coverage is 50% (only 'query' has description). The tool description does not explain either parameter; it only mentions the resource. The schema already describes 'query' as a JMESPath expression, but 'search' remains entirely undocumented in both schema and description.

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 verb 'List' and the resource 'ZIA VPN credentials', and adds a key behavioral constraint: 'PSK never returned'. This differentiates the tool from a detail retrieval tool like `zia_get_vpn_credential`, but it does not explicitly distinguish between listing and other list tools.

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 such as `zia_get_vpn_credential` for details, or any prerequisites or context. It only declares what the tool does.

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