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

Annotations declare write/openWorld/destructive=false, but the description adds substantial behavioral context beyond them: an async placement state (NOT PLACEABLE YET), the wait_for_asset handoff, size ceilings (2 MB data, 10 MB font), and that fonts return a family name. It doesn't cover auth or failure modes, but the added value is strong.

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?

Front-loaded with the core action and the key async caveat, which is good. However it is dense and slightly overgrown, with an interstitial example URL and a fragmented sentence ('So does a font file...') that reduce readability without adding much.

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?

No output schema, so the description carries return-value burden and does so: it states an Asset ID is returned, the ready/placeable workflow, and font family naming. Combined with the partial schema it is close to complete, though the start/end range behavior is handled only by the schema, not the description.

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 60%; the two undocumented params (url, fileName) are exactly the ones the description clarifies ('direct HTTPS URL', 'filename including extension'). The projectId/start/end params already carry schema descriptions, so the description fills the real gaps rather than repeating them.

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 ('Import media from a direct HTTPS URL') and enumerates the media kinds it accepts (video, data files, fonts). It is clearly distinct from siblings like import_stock or import_gif by being URL-driven, though it does not explicitly name those alternatives.

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 procedural guidance: supply a filename with extension, and if the result says NOT PLACEABLE YET, call wait_for_asset before use. It explains the accepted data-file and font scenarios, but leaves implicit when to prefer this over upload_files or the other import_* siblings.

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