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

Without annotations, the description carries the full burden of behavioral disclosure. It reveals the output format (transparent PNG) and customization options, but does not explain the interaction model (e.g., how the user inputs text or downloads the result) or any limitations. This is partial transparency, as it adds some behavioral context beyond the tool name.

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 a single, concise sentence that front-loads the core purpose (generating transparent PNG telop images) and then lists customization options. Every word contributes meaning, with no filler or redundancy.

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?

The description covers the core output and customization but omits the workflow (how a user interacts with the browser-based tool) and any prerequisites or limitations. While the tool appears simple (no parameters, no output schema), the lack of clarity on how the agent/user uses the tool leaves a gap, making it minimally complete.

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?

The input schema is empty (0 parameters), so the baseline is 4. The description adds value by mentioning customization aspects (font, color, shadow) that imply the tool has configurable options, even though they are not exposed as API parameters. This helps the agent understand the tool's capabilities beyond the empty schema.

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: generating telop images for videos as transparent PNGs, with customization for font, color, and shadow. This is a specific verb+resource combination that distinguishes it from generic image tools, though it does not explicitly compare to similar siblings like yt-telop.

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 no guidance on when to use this tool versus alternatives such as yt-telop, text-overlay-maker, or eyecatch-maker. It only mentions it is browser-based, which is a contextual hint but not an explicit usage guideline.

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