list_instances

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

No annotations are provided, and the description does not disclose behavioral traits such as pagination, authentication requirements, rate limits, or the format of the response. It simply states what the tool does without adding behavioral context beyond the basic listing action.

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 sentence with 14 words, front-loading the verb and resource. Every word is meaningful, and there is no redundancy or unnecessary detail.

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 low complexity and full schema coverage, the description covers the core functionality. However, without an output schema, the description could be enhanced by specifying what fields are returned or indicating potential limitations (e.g., no pagination details).

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 description mentions filtering by region or state, but the input schema already provides detailed descriptions for both parameters (including examples for region). Since schema coverage is 100%, the description adds minimal additional semantic value.

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 'managed server instances' with specific examples (AWS EC2, OVH, custom servers). It distinguishes the tool from siblings like 'list_server_memories' and 'get_server_info', which have different purposes.

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 mentions optional filtering but does not explicitly state when to use this tool versus alternatives (e.g., using 'get_server_info' for a single instance). No guidance on prerequisites or when not to use it.

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