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

Annotations already disclose readOnly=false, destructiveHint=false and non-idempotency, so safety needs little extra. The description still adds real behavioral context: the output is a *new* PNG asset (originals are preserved), the transparency/colour treatment, and that the call costs no credits. It stops short of describing failure modes or latency.

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?

Four sentences, front-loaded with the outcome, then usage, then the sibling alternative and cost. The middle sentence is a little overloaded ('transparent background and the subject's own colours') but every sentence carries information an agent needs.

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, the description correctly supplies the return value ('Returns the new Asset ID') and where to use it, plus a cost statement. The gap is the unexplained assetId input, the only thing an agent must resolve to call it correctly.

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 50%: projectId is documented in the schema while assetId has no description at all, and the prose never clarifies what an assetId is or must refer to. The mention of the returned 'new Asset ID' only indirectly hints at the input's form. Baseline 3 for partial schema coverage plus a small indirect clue.

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?

Names a specific verb+resource ('Remove the background of a ready image asset') and immediately narrows the domain to logos and product photos. It explicitly distinguishes itself from cutout_person, so an agent can pick between them without opening either schema.

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?

States the use case ('on a logo or product the person uploaded before it sits on footage or a colour') and the exclusion ('for a person in a video, use cutout_person'). Also routes the result onward with 'place it with patch_film like any image', covering both before and after conditions.

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