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

With no annotations, the description carries the full behavioral burden. It says 'add', but does not disclose what happens on channel collisions, how autoChannel interacts with an explicit channel, what relativeStartTime requires (a pinned shot), permission needs, or whether the call is idempotent. For a 15-parameter mutation, this is a substantial 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?

A single dense sentence with the action front-loaded and no filler. It is efficient, though cramming six feature groups into one clause makes it read as a feature list rather than guiding the caller.

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 15-parameter mutation with no annotations and no output schema, the description is adequate at the surface level but omits the cross-parameter interactions (autoChannel vs channel, relativeStartTime requiring pinnedToShotId) and any failure/error behavior an agent would want before calling.

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 the schema already documents all 15 parameters in detail. The description groups them into themes (placement, trim, fades, volume automation, channel, shot pinning), which is a useful mental model but adds no syntax or interaction detail beyond the schema.

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) and resource (audio track on edit timeline) and scopes the source as an 'existing workspace audio media item', which implicitly separates it from generate_audio_track. It does not name any sibling explicitly, but the resource and the source constraint are unambiguous.

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?

Usage is only implied by the word 'existing' — the agent can infer this places already-uploaded audio rather than synthesizing it, but the description gives no explicit when-to-use, prerequisites, or when to prefer generate_audio_track instead.

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