Upload a Google Play store listing image

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

Beyond the annotations (destructiveHint=true, idempotentHint=false, openWorldHint=true), the description adds real context: the operation is additive ('Existing images remain'), it is staged rather than immediate ('Changes take effect after commit_edit'), and the source must be a local PNG or JPEG. There is mild tension with destructiveHint=true, but 'existing images remain' reads as scoping the side effect rather than contradicting it; size/format limits and permission requirements are still unstated.

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 short sentences, with the mutation signal front-loaded in capitals and the commit dependency placed last where it belongs. No wasted wording.

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 five-parameter mutation with no output schema and no schema descriptions, the staging model and additive behavior are well covered. Gaps remain around the edit lifecycle parameters, image constraints (dimensions/size), and what happens if an image of the same type already exists.

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 0%, so the description carries the burden, and it does add meaning for filePath (local file, PNG or JPEG only) and for language/imageType as the target selectors. It says nothing about editId (which edit session) or packageName, leaving two of five required parameters undifferentiated from the bare schema types.

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 gives a specific verb and resource ('uploads a local PNG or JPEG and adds it to the selected language and image type'), which is enough to tell it apart from the read-side sibling list_listing_images. It does not name any sibling explicitly, so an agent must infer that this is the only listing-image upload tool.

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 states the workflow requirement clearly: the upload is staged inside an app edit and only takes effect after commit_edit, which implies create_edit must precede it. It stops short of naming alternatives or stating when not to use it (e.g., re-uploading to replace an image).

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