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

No annotations are provided, so the description carries the full disclosure burden. It details per-track effect recipes (compressor+EQ, saturation, reverb/delay, sidechain) and specifies genre-specific variations. It also discloses sidechain behavior and returns the effects added per track, giving full visibility into the operation's outcome.

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?

The description uses tight lead sentences, bulleted recipe lists, a compact parameter explanation block, and two clarifying examples. Each section earns its place without redundancy, and the most important information (purpose and workflow) is front-loaded.

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?

With 4 parameters and zero schema descriptions, this description covers all necessary invocation context: usage scenario, workflow position, genre-specific behavior, parameter constraints, and return value. The output schema exists, and the description states it returns 'effects added per track and parameter values', so no critical information is missing.

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 0%, but the description thoroughly compensates for every parameter: genre lists the 11 allowed values, unit_index is defined as 'AU index with the arrangement tracks', num_tracks is specified as '3 or 4, must match arrangement', and sidechain is described as 'drums→bass' with genre-family guidance. This is exactly what the agent needs to invoke correctly.

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?

Description opens with 'Apply genre-specific mixing effects to tracks after creating an arrangement' – a specific verb+resource+context. It clearly distinguishes itself from sibling tools like create_*arrangement and manual effect-chaining calls by positioning itself as the connection between arrangement creation and rendering.

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?

Explicitly places tool in the workflow: 'Closes the loop: create arrangement → apply genre mix → ready to render.' It also states this replaces '10-20 manual add_effect + set_effect_parameter calls', directly identifying the alternative. Examples pair it with specific arrangement-creation functions (create_dnb_arrangement, create_jazz_arrangement), making when-to-use unmistakable.

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