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

Annotations already declare read-only, idempotent, non-destructive behavior, and the description adds useful context: the required scope (`images:manage`), exact endpoint mapping, signed preview URLs, billing/rate-limit behavior, and a warning not to invent other paths. This goes beyond what annotations alone provide.

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 compact and front-loaded with the core behavior, then uses bold labels for scope and endpoint details. Each sentence carries operational value, particularly the rate-limit note and the 'do not invent other paths' warning.

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?

For a simple read-only list operation with one optional parameter and no output schema, the description is sufficient: it clearly states scope, output content, endpoint, and API policy. Nothing critical is missing for an agent to invoke it correctly.

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 only parameter, x_app_id, is fully documented in the schema with 100% coverage, including guidance for multi-app orgs. The description does not add additional parameter-specific semantics, so the baseline 3 applies.

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 states a specific action ('List images') and clarifies scope ('all images for the current app') plus a distinct output feature ('signed preview URLs'). This differentiates it from image mutation/usage siblings such as uploadImage, deleteImage, and getImageUsage.

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 implies when to use the tool—when you need all images for the current app—but it never explicitly states when to prefer this over related image tools or when not to use it. It provides operational constraints such as the same API/billing/rate limits, but no explicit alternative or exclusion guidance.

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