Index a video

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

Annotations only declare destructiveHint=false, so the description carries the real behavioral burden and does so well: it discloses that the operation is asynchronous and long-running ('takes minutes and runs in the background'), what it extracts (thumbnails, duration, optionally transcription), and an authorization requirement (Editor role). These are exactly the traits an agent cannot infer from structured fields.

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 sentences, each earning its place: purpose/precondition, what it produces, then runtime and follow-up. Front-loaded and free of 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?

No output schema exists, but the description compensates by explaining the async nature, the polling mechanism, and the role requirement, which is everything an agent needs to invoke and track this correctly. Nothing material is missing for a one-parameter 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?

There is a single parameter with 100% schema description coverage, so the schema already documents videoId fully and the description adds nothing about it. Baseline 3 is appropriate when the schema does all the parameter work.

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 (index a video) and scopes it precisely to catalog videos lacking scene thumbnails. It also distinguishes itself from the sibling used afterward (get_video_scenes) and implicitly from list_videos_needing_indexing, so an agent can route without opening a schema.

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 an explicit precondition for use ('in the catalog but has no scene thumbnails yet') and names the correct alternative action for a different need (poll get_video_scenes to follow progress). The only minor omission is a direct pointer to list_videos_needing_indexing for discovery, but the when-to-use guidance is unambiguous.

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