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

Annotations already declare non-read-only, idempotent, non-destructive behavior, so the bar is lower. The description adds the concrete auth requirement (demos:read, demos:write), which is exactly the kind of context annotations cannot express; what it omits is whether other scenes shift and what happens on an out-of-range position.

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 short sentences, front-loaded with the action and the key positional convention, followed by the permission prerequisite. Nothing is wasted or buried.

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 3-required-param, non-destructive reordering mutation with annotations and no output schema, this covers action, key parameter convention, and auth scopes. An agent has enough to call it correctly; further return-value detail is not needed since no output schema exists.

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 67% – sceneId and videoId are documented, but position has no schema description. The description compensates by explaining that 0 means first, giving meaning the schema does not; the upper bound (max 40) and shifting behavior remain unexplained.

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 ("Moves a scene") plus the destination semantics ("to another position (0 = first)"), which is more than the title alone conveys. It does not differentiate from the closely named sibling move_step or from update_scene, so an agent must infer which one reorders vs. edits.

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 parenthetical about position 0 implies a reordering use case, but the description never states when to use this instead of move_step or update_scene, nor any preconditions beyond the permission scopes. Usage is implied rather than guided.

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