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

Annotations already declare it is a non-read-only, non-idempotent mutation; the description adds valuable context beyond them — it is asynchronous (poll via get_generation), consumes account entitlements/credits, and requires the source to already exist in the account. It does not cover auth requirements or reversibility, keeping it from a 5.

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?

Three sentences, front-loaded with the core conversion benefit and followed by the creation/entitlement and async details. Slight marketing padding ('scale to any size without blur') but overall tight and well-ordered.

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 an output schema present, return values need no explanation, and the description covers the creation semantics, credit use, and async follow-up. The main remaining gap is the structure of the source parameter, which neither the schema nor description documents.

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 0% on a required, non-trivial param that is a union of upload-source and generation-source variants. The description only hints 'from an image already in the account' and never explains the two accepted source types, so it does not compensate for the coverage gap.

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?

States a specific verb+resource ('Convert a raster image ... into crisp vector paths'), which is a distinctive operation distinguishing it from image siblings like upscale_image or remove_image_background. It stops short of explicitly naming an alternative, so it is clear but not sibling-differentiated by the standard of a 5.

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?

Implies usage (raster in → vector out, source must already be in the account) and gives a workflow hint that get_generation waits for the result. However it offers no explicit when-to-use vs when-not-to-use guidance or naming of competing tools, leaving usage to inference.

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