setAudio

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

Annotations declare a non-read-only, non-destructive, closed-world mutation. The description adds real behavioral context beyond that: 'Only the fields you pass are changed' establishes PATCH-style partial-update semantics, and 'the whole track is edited, not one fragment' warns that splits are not targeted. It does not state auth or permission requirements, but for this profile the added semantics are meaningful and consistent with annotations.

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 paragraph with the core verbs front-loaded before the use-case examples and the partial-edit caveat. Nearly every clause adds information, though the enumeration is long enough that it borders on listy.

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 an 11-parameter mutation with no output schema, the description covers update semantics, scope (whole track vs. fragment), and the meaning of most editable fields. An agent has enough to invoke it correctly; only explicit required/optional signaling and permission notes are absent.

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 9% (just projectId), so the description must carry the burden, and it largely does: gainDb (ducking), fadeInMs/fadeOutMs with the 0-5000 ms range, offsetSec (which part of the file plays), kind (voiceover/music lanes), plus the move/resize/mute/loop fields implied by the verb list. It adds units and intent the bare schema lacks, though it doesn't spell out startSec/endSec or the gainDb range the schema enforces.

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?

Opens with a specific set of verbs (move, resize, re-level, re-lane, mute, loop, fade, re-point) applied to a concrete resource: an existing audio track identified by id. This clearly separates it from siblings like addAudio (new track) and removeMedia, so an agent can select it without opening a schema.

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?

Gives concrete use cases — duck a bed under narration via gainDb, fade in/out, offsetSec to shift the played portion, kind to move between voiceover and music lanes. This tells the agent when the tool is the right choice. It does not explicitly name an alternative tool or state exclusions, so it stops short of a 5.

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