fl_set_channel_mix

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

Annotations already indicate this is a non-read-only, non-idempotent, potentially destructive mutation. The description adds a useful, non-annotated behavior: 'per-field readback proof' shows the tool returns verification of what was applied. It does not disclose the concurrency guards or failure refusal semantics, but those are described in the schema properties such as session_fingerprint and expected_before, so the added value is modest.

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 a single, well-formed sentence with the key verb and resource front-loaded. Every word contributes to understanding (set, channel, volume, pan, mute, readback proof), with no redundant explanation or filler.

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 rich annotations, a complete input schema, and an output schema, the description provides enough orientation for a correct call. The 'and/or' and 'per-field readback proof' cover the most useful non-schemaable context; missing guidance about concurrency guards is already place in schema parameter descriptions.

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 each parameter's meaning. The description's 'and/or' suggests fields can be updated individually or together, but it adds little beyond the schema's explicit null defaults and descriptions. A baseline of 3 is appropriate when the schema carries the weight.

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 states a specific verb and resource: it sets channel volume, pan, and/or mute, and adds a distinctive 'readback proof' behavior. This distinguishes it from mixer-track siblings like fl_set_mixer_volume, fl_set_mixer_pan, and fl_set_mixer_mute by making the channel scope explicit.

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 gives no explicit guidance about when to use this tool versus alternatives. It does not mention that it targets channel rack channels rather than mixer tracks, nor does it note the expected_before/session_fingerprint guards, leaving any usage decision to inference.

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