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

Goes well beyond the given annotations: discloses the cost model ("spends NO tokens; counts against the daily utility allowance") and a strong safety disclosure that the returned `prompt` is untrusted data, including the prompt-injection risk from words drawn in the image. No contradiction with `readOnlyHint: false` / `openWorldHint: true`.

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?

Front-loads the return value and the follow-on action, then layers cost and safety notes. Dense with parentheses and semicolons, which slightly hurts scanability, but no sentence is filler.

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 single-parameter tool with no output schema, the description covers the return value (`prompt`), where the input can come from, the failure case, the cost, and the security handling of the output. Nothing material is left for the agent to infer.

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 coverage is 100%, so the baseline is 3, but the description adds real semantic constraints the schema lacks: accepted URL sources are an image url, an `upload_media` url, or a generated image's url, and cross-account aicut images are rejected. The "unchanged" requirement in the schema is complemented, not repeated.

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 concrete verb+resource: returns a text `prompt` that would regenerate the given image, equating it to the web app's "copy prompt from image". It also names the downstream sibling (`generate_image`) so the agent can place it in a workflow rather than guessing.

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?

Explicitly says what to do with the result ("pass it to `generate_image`") and gives an exclusion case (another account's aicut image is rejected). It stops short of contrasting with siblings like `get_analysis` or `describe_cast_member`, so the routing picture is clear but not exhaustive.

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