download_artifact

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

Annotations already declare readOnly=false, destructive=false, openWorld=false; the description adds real context on top: it writes into a configured downloads directory, returns an absolute local path, and streams large videos to disk rather than buffering. It does not cover overwrite behavior or failure modes.

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 short sentences, front-loaded with the action and destination, then return behavior and the streaming nuance. No filler sentences.

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?

Return value is covered by an output schema, and the description still helpfully previews the absolute path, but with two undocumented parameters and no guidance on job state requirements or filename control, an agent lacks enough to call it confidently in edge cases.

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 description coverage is 0% for both parameters, so the description carries the full burden, yet it never mentions job_id or the 'name' parameter (whose default 'result.mp4' strongly implies a filename choice). An agent must guess whether 'name' sets the output filename or the artifact identifier.

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 ('Download a completed artifact') and names the destination ('configured local downloads directory'), which separates it from view_artifact by implying a persisted local file rather than an in-place preview. It stops short of explicitly contrasting with view_artifact.

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 qualifier 'completed' implies a precondition (the job must be finished), which is useful, but there is no explicit when-to-use versus view_artifact or upload_media, and no statement about what happens if the job is still running.

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