Upload template media

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

No annotations are provided, so the description must carry transparency. It does disclose the external write ('Upload ... to Meta') and that the handle is reusable, which is useful. However, it does not mention permissions, rate limits, irreversibility, or failure modes, leaving some side-effect behavior undisclosed.

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 concise sentences with no filler. The primary action is front-loaded, and the usage example is compact and immediately actionable. 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?

Since there is no output schema, explaining the return value is essential—the description does this and even demonstrates how to use the header_handle. It lacks minor details like supported MIME type examples or whether the URL must be globally accessible, but these are partially covered by the schema and are not blocking.

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%, and both parameters already have clear descriptions. The description adds no additional meaning beyond the schema; it reinforces that the URL must be public, but that is already stated. Baseline 3 applies.

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 operation ('Upload a public media URL ... to Meta'), the resource (media for a template header), and the output ('reusable header_handle'). It clearly differentiates from sibling tools by focusing on the media upload step for a HEADER component, rather than template creation or messaging.

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?

Provides clear context: this tool is for obtaining a header_handle, and the description shows exactly how to embed it in a HEADER component. It implies the workflow (upload first, then reuse handle in template) but does not explicitly name alternatives or say when not to use it.

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