Add one or many videos to a folder in a single call

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

Annotations already cover the safety profile (readOnlyHint=false, idempotentHint=true, destructiveHint=false), and the description adds a genuinely important behavioral fact not in the structured data: 'A video lives in one folder at a time, so this moves it rather than copying it.' It does not state what happens when the video is already in the destination folder or any permission requirements.

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 tight sentences, front-loaded with the core action, then the efficiency rationale, then the crucial move-vs-copy semantics. No 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?

For a two-parameter mutation with annotations covering safety and idempotency and no output schema, the description supplies the batch rationale and the move semantics an agent needs. It leaves edge-case behavior (already-in-folder, folder limits) unspecified, a minor gap.

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 100%, so folder_id and video_ids (including the 100-item cap) are already documented in the schema. The description's 'pass the whole list' reinforces the array parameter but adds no new syntax or format detail, so the 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 verb (add), resource (videos), and target (folder), plus the batch scope 'one or many ... in a single call'. It is immediately distinguishable from the sibling remove_videos_from_folder and from per-item 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?

Explicitly tells the agent when to prefer this tool: 'the efficient way to file a back catalog: pass the whole list rather than calling once per video'. It does not name a when-not case or an alternative sibling tool, but the usage condition is clear.

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