set_sidechain

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

Discloses a significant non-obvious side effect: it will create a new Compressor at the end of the chain if none exists (device-resolution precedence spelled out). It also details the state it sets (S/C On, threshold, ratio, attack, release) and that enabled=False disables rather than removes, which is well beyond the safety hints in 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?

Purpose and use case are front-loaded, then device resolution, then parameters, then a worked example. Dense but every clause carries information; mild formatting/wrapping awkwardness keeps it from a 5.

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 mutation tool with no output schema and 0% schema coverage, the description covers device resolution, side effects, and parameter meaning thoroughly. Minor gaps remain (e.g. what happens to pre-existing compressor settings not mentioned, or the response), but nothing that would cause a mis-call.

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 coverage is 0%, so the description must carry the load and it does: it documents source (with its audio-output requirement), channel (all three values including the default), device fallback order, enabled, and the four compressor values. Almost every one of the 9 parameters gains meaning not present in 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?

States a specific verb and resource ('Duck `track` whenever `source` plays: sidechain compression') plus a concrete use case (bass/pad pumping to the kick). No sibling tool does sidechain compression, and the description makes that scope unmistakable.

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?

Explains when this applies, names the required device (Live's Compressor) and why alternatives cannot be used ('the only device whose sidechain input the API can route'), and clarifies the tricky source case (use the drum track for a kick). It stops short of explicitly naming an alternative tool or stating when not to use it.

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