Set Channel Banner

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

Annotations already declare the write, destructive, idempotent, and open-world profile, so the description does not need to restate them. It adds the 101-unit quota, a useful operational cost, but omits permission requirements, what happens to an existing banner, and other behavioral details beyond quota and image constraints.

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 short sentences with zero filler. The purpose is front-loaded, followed by necessary input requirements and quota in a compact structure.

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 an output schema, full schema descriptions, and annotations covering safety, the description supplies the key missing input constraints and quota. It could mention replacement behavior or channel-selection alternatives, but those gaps are minor for a simple banner-setting tool.

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%, so the schema already documents both parameters. The description adds meaningful constraints for the image parameter—16:9 aspect ratio, minimum 2048x1152, maximum 6 MB—that go beyond the schema's 'Path to a JPEG or PNG.' It does not add anything for my_channel, but the schema covers that fully.

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 states a specific verb and resource: 'Upload and set your channel's banner.' This clearly separates it from sibling mutators such as set_watermark and set_thumbnail, which operate on different channel assets.

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 or alternatives are provided. The description focuses on image requirements and quota, not on when to choose this over set_watermark, update_channel, or other banner-related operations.

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