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

With no annotations, the description carries full burden. It discloses that it adds effects per track with genre-specific recipes, sidechain behavior, and returns effects added per track. It could mention reversibility or idempotency, but it is still transparent enough for an agent.

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 is well-structured: a short header, followed by workflow context, bullet points detailing genre recipes, parameter explanations, and an example. Every sentence adds value and it is front-loaded with the main purpose.

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?

Given the tool's complexity (4 params, output schema exists), the description is complete: it explains the workflow, genre-specific behavior, parameter constraints, and what is returned. The presence of an output schema reduces the need for return value detail, and the description covers the rest thoroughly.

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%, so the description must compensate fully. It does: it lists valid genre values, explains unit_index, num_tracks (must match arrangement), and sidechain (with guidance on when to set True/False). This adds critical meaning beyond the bare 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?

The description clearly states the tool applies genre-specific mixing effects to tracks after creating an arrangement. It uses specific verbs and resources (apply, genre mix) and distinguishes itself from sibling tools like apply_full_mix or apply_mix_preset by being part of a pipeline (create arrangement → apply genre mix → ready to render).

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?

The description explicitly says 'Closes the loop: create arrangement → apply genre mix → ready to render' and mentions it replaces 10-20 manual calls, giving clear context for when to use it. However, it does not explicitly state when not to use it or compare with alternatives like apply_full_mix, so it is not a perfect 5.

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