Check Generation Status

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

Even with annotations indicating readOnlyHint and idempotentHint, the description adds valuable behavioral context: it returns a 'short JSON status — no image data, no heavy UI,' which signals lightweight polling. It also enumerates possible return values ('completed', 'generating', 'failed') and the associated next steps. This goes beyond annotations and helps the agent understand expected behavior.

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?

The description is compact and front-loaded. The first sentence states the purpose, the second gives usage context, and the bulleted list concisely explains the status outcomes. No unnecessary words or repetition; every sentence earns its place.

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 simple polling tool with one parameter and an output schema, the description is complete. It explains the return statuses, the expected next actions, and notes that it returns no image data. With annotations covering safety and idempotency, and the output schema documenting return structure, the description sufficiently covers all needed context.

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% (image_id is fully described as 'The image_id returned by generate_image'). The description doesn't add extra parameter details beyond referencing generate_image, which is consistent with the schema. Since the schema already documents the parameter well, a baseline score of 3 is appropriate.

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 clearly states the tool's function: 'Check whether a background image generation has finished.' This is a specific verb+resource (check status of generation) and clearly differentiates from siblings like show_image (display) and edit_image (edit). It also places the tool in the workflow by saying 'Call this after generate_image'.

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?

The description provides explicit when-to-use guidance: 'Call this after generate_image to wait for completion.' It also gives context on how to handle each returned status, including waiting and re-checking or advancing to show_image. This effectively tells the agent when and how to use the tool in a polling loop.

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