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

Annotations already establish that this is a non-destructive mutation, so the description adds valuable context beyond them: credit consumption, asynchronous completion, immediate return of drawing_id, and a multi-minute runtime. It does not cover permissions, failure modes, or cancellation behavior, but the core behavioral traits are disclosed.

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 tightly written sentences: purpose first, cost second, asynchronous follow-up third. Every sentence adds distinct information and there is no filler.

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 tool with six parameters, a nested settings object, and zero schema descriptions, the description is not complete enough. It explains the return and follow-up flow but leaves all input parameters undocumented, which is a major gap for correct invocation.

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 0%, so the description must carry parameter meaning, yet it explains none of the six parameters. It vaguely gestures at credits and quote but does not clarify image, title, settings, upload_id, max_credits, or quote_version, and the nested settings object is entirely unaddressed.

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 and resource: "Draw a picture as a whiteboard animation." This is clearly distinct from get_drawing and list_drawings, though it does not differentiate from creation-adjacent siblings like create_upload or render_link.

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?

Gives clear usage context: it spends credits and points to quote, and it explains the follow-up step with get_drawing after the immediate drawing_id response. It does not state when not to use it or compare it with other creation tools, but the lifecycle guidance is strong.

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