live_set_channel

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

With no annotations, the description carries the full burden. It does disclose the return shape ('Returns before/after') and the value domain (normalised 0..1, pan 0.5 = centre), which is real added context, but it says nothing about failure behaviour (unknown channel label), whether the change is undoable via live_undo, or persistence to the song.

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?

Three short sentences: purpose first, then value semantics, then return format. No filler, no restatement of the tool name, and the most decision-relevant facts are 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?

For a narrow, three-parameter mutation with no output schema, the description covers purpose, value encoding, and return value adequately. It still omits prerequisites (a live Studio One connection), error cases, and whether the mutation is reversible, which matters given there is no annotation safety profile.

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 only 33% (just 'channel'), so the description has to compensate, and it does for the riskiest parameter: 'value' is only typed as number in the schema, yet the description pins down the normalised ranges and the 0.5 centre convention per field. The field enum and channel label semantics are left to the 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 concrete verb and resource ('Change one mixer channel') and scopes it to 'the running Studio One', which cleanly separates it from read-side siblings like live_channels and live_track_state. It stops short of naming a sibling or stating the single-field-per-call constraint, so it is clear but not fully differentiated.

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?

There is no when-to-use, when-not, or alternative guidance at all. In a 26-tool live-* family that includes live_command and live_eval, the agent gets no help deciding whether a channel change belongs here or in a generic command tool.

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