generate_image

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

With no annotations, the description must carry the behavioral burden. It usefully discloses that spend-guard pricing/checking happens before generation, implying a possible rejection or approval path (matching the approval_id parameter). However it omits everything else: output location side effects (save_to), watermarking behavior, batch semantics, and failure modes.

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?

Two tight sentences, front-loaded with the core action and cost-gate note; nothing is wasted. It is arguably too terse for a 9-parameter paid tool, but as a structure it is clean.

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?

An output schema exists so return values need no explanation, but the tool takes 9 parameters, incurs cost, and is gated by an approval flow. An 11-word description cannot make an agent confident about the approval_id/max_images/save_to interactions, leaving it materially incomplete.

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 only 56% across 9 parameters, and the description clarifies none of them. Undocumented parameters like approval_id and watermark get no explanation of their role or when they matter, so the description does not compensate for the coverage gap.

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 specific verb+resource: 'Make an image with Seedream,' which is unambiguous about the operation and the backing model. Sibling tools are all video/spend/status related, so the image-generation purpose is naturally distinguishable, but the description does not explicitly name them.

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?

No when-to-use guidance, no alternatives, no prerequisites spelled out. The phrase 'checked by the spend guard first' hints that a cost/approval flow is involved but never names estimate_cost or preapprove_spend, nor explains when generation will be blocked.

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