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

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false, and destructiveHint=false, so the safety profile is covered. The description adds nothing on top — it does not explain the async callback behavior implied by callback_id/idempotency_key, expected latency, or what the erasure actually does to the source image.

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?

At four characters this is not conciseness but under-specification — there is no front-loaded information to structure. Brevity here removes value rather than tightening it.

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 10-parameter, non-read-only image generation tool with no output schema, the description should at minimum explain the mask/instruction workflow and the asynchronous result retrieval implied by callback_id. None of that is present, leaving the agent to infer the entire invocation contract from field names.

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% across all 10 parameters, so the schema itself documents each field; the baseline for a fully annotated schema is 3. The description contributes no additional meaning about how mask_url, instruction, or method interact, so it neither helps nor hurts.

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?

"AI 图片消除" is essentially a Chinese restatement of the tool name (image_magic_eraser) — an AI image erasure tool. It conveys a generic verb+resource but offers no detail about what is being erased (object removal? background? watermark?) and does not distinguish it from siblings like image_cutout or video_magic_eraser.

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?

There is no guidance on when to use this tool versus image_cutout, image_enhance, or the video counterpart. No prerequisites, required inputs, or exclusions are stated anywhere in the description.

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