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

The annotations already declare readOnlyHint, idempotentHint, and destructiveHint false. The description goes further by explaining the meaning of `template_refs`, `pass_refs_count`, and `safe_to_delete`, plus the `images:manage` scope, the OpenAPI path mapping, and the same HTTP API/rate-limit behavior. This adds substantial context beyond structured fields.

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 well-structured: a one-line summary, a purpose statement, a bulleted list of output fields, and concise operational notes. Every sentence adds value, including the guardrail about not inventing other paths.

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?

With no output schema present, the description compensates by explaining the return fields and their semantics. It also covers the required scope, API mapping, and operational constraints, making the tool fully invocable without needing external documentation.

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%, with clear descriptions for `id` and `x_app_id`. The description does not add significant parameter semantics beyond what the schema already provides, so 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 states a specific verb and resource: 'Get image usage / reference counts' and explains that it reports how an image is referenced across templates and passes. This clearly distinguishes it from sibling tools like listImages, uploadImage, and deleteImage by focusing on reference counts rather than listing, uploading, or deleting.

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 explicitly identifies when to use the tool: 'Useful before DELETE to confirm an image is unused, or to find which templates a shared asset is attached to.' It does not explicitly name alternatives or exclusion cases, but the use cases are clear enough to guide an agent.

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