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

With no annotations, the description carries the full behavioral burden. It discloses the render-order semantics but says nothing about required permissions, whether a new track is empty, what identifier is returned for later item placement, or whether ordering collisions are resolved. For a mutation tool this is a significant gap.

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 tight sentences with the creation purpose front-loaded and the ordering rule immediately after. Nothing is wasted, though the ordering sentence is partly redundant with the schema.

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?

There is no output schema, so the description would ideally state what creating a track returns (e.g., a track ID needed by add_overlay_item). It is adequate for a simple creation call but leaves the return contract and lifecycle context unaddressed.

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 name, order, locked, visible and the two IDs are already documented. The description's stacking statement merely restates the schema's 'Stack order; higher renders on top' and adds no new parameter meaning.

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 (Create) and resource (overlay track) plus the kinds of overlay content it supports (text, image, video). It distinguishes the track-level tool from item-level siblings such as add_text_overlay and add_media_overlay, though it never names them explicitly.

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?

No guidance on when to create a new track versus reusing an existing one, and no mention of the alternative add_audio_track or of the update_overlay_track/delete_overlay_track lifecycle. The only conditional information is the stacking behavior, which is not usage guidance.

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