compare_moles

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

No annotations are provided, so the description carries the burden. It discloses that the core behavior is identifying differences between the two photos, which is meaningful, but it doesn't clarify the form of the result, whether the operation is read-only beyond its name, or what kind of image constraints apply.

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?

Two sentences, no repeated or irrelevant words. The primary action is front-loaded and the usage trigger follows naturally.

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?

The simple three-required-parameter tool is fully invocable with the schema plus description. The main gap: no output schema exists and the description doesn't formally state the result object, though the intended response kind (identified changes) is understandable.

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%, so all three parameters are already clearly described without any extra input documentation. The tool description adds little beyond image-related context, so the schema does the important lifting.

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 names a specific verb and action on a specific resource: compare two mole images to identify changes. The mole-image resource also clearly distinguishes it from the only similar sibling, compare_model_runs, so an agent can select the correct tool by description alone.

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?

It says explicitly Use this when a user asks about changes between photos, which is a clear usage trigger. It does not provide when-not-to-use guidance or a named alternative, so it does not reach the eplicit exclusions level.

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