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

Annotations already establish this is a non-read-only, non-destructive, closed-world mutation. The description adds one genuine behavioral fact beyond them: visual tracks are inserted on top by default, which tells the agent the default ordering. It still omits what happens when index is supplied, what a created track's identity/name defaults to, and whether adding a video vs audio track has different placement rules.

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 followed by the one non-obvious default. No filler, though the second sentence carries nearly all the added value and the first merely restates the name.

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?

A mutation tool with four parameters, an enum, and only 25% schema coverage needs more than two sentences. An agent cannot tell from the description how kind/name/index interact, what a track is within a project, or what is returned, and there is no output schema to fall back on.

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 only 25% — just projectId carries a description. The description says nothing about kind (video/audio/text), name, or index, so it does not compensate for the undocumented parameters; only the insertion-order remark implicitly gestures at index.

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?

Evokes a specific verb and resource ("Add a track") in the timeline sense, which is unambiguous within this server's vocabulary. It does not distinguish itself from nearby siblings such as add_clip or add_text, nor does it describe the kind of track, but the core action is clear.

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?

There is no when-to-use guidance, no mention of prerequisites, and no pointer to alternatives like add_clip (which presumably creates content on an existing track) or move_track. The only sentence about placement describes default behavior, not when to choose this tool.

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