list_images

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

Describes default zone behavior and arch filtering, which adds context beyond the tool name. However, with no annotations, it doesn't disclose whether the operation is read-only, any rate limits, or authentication requirements. The description carries the full burden for behavioral disclosure, but for a simple listing tool, the behavior is fairly clear.

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 two sentences plus a succinct argument list. It is front-loaded with the main purpose and every line provides useful information without rambling.

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 simplicity (2 optional parameters) and presence of an output schema, the description adequately covers purpose and parameter behavior. It doesn't need to describe return values because the output schema exists, and no annotations are needed for a straightforward list operation.

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 fully explains both parameters, including the zone example and default behavior, and the architecture filter values and default. This compensates for the 0% schema description coverage, adding value beyond the schema's type/default only.

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?

Clearly states the tool lists available instance images, distinguishing it from sibling list_instances by naming the resource. Uses specific verb 'List' and resource 'instance images'.

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?

Provides parameter defaults and filtering options but does not explicitly state when to use this tool versus alternatives like list_instances or when not to use it. The intended use is implied by the name and description.

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