set_label

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

Annotations already declare non-destructive, non-read-only, closed-world mutation, so the safety profile is covered structurally. The description adds genuinely useful behavior beyond that: Live snaps the requested colour to the nearest entry in its chooser, meaning the write may not be exact. It does not say whether the operation is idempotent, what happens if the track/slot does not exist, or what is returned.

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 targeting rule is front-loaded in the first sentence and the colour-snapping caveat follows. The role-based colour convention (drums red, scenes by song section) is helpful but slightly advisory padding; overall there is little waste across four lines.

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 5-optional-parameter mutation with no output schema and no per-parameter documentation, the description covers the highest-risk gaps: which combination targets what, and that colours are normalized. Missing only edge-case behavior such as conflicting arguments, no-op calls, and error conditions on invalid indices.

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 carries real weight here and it does explain the addressing semantics of 'track', 'slot' and 'scene' - the most important part. However, 'name' and 'color' are only implied via 'rename and/or colour', and the crucial default that unset parameters leave the existing label untouched is left to be inferred from 'and/or'.

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 opens with a concrete verb pair (rename and/or colour) and the three resources it applies to, then immediately disambiguates them by argument shape: 'track alone', 'track + slot', 'scene alone'. No sibling tool in the list performs labeling, so an agent can select this unambiguously.

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?

It gives clear operational context by mapping each target type to a parameter combination, which is effectively when-to-use guidance for the three modes. It stops short of explicit exclusions - it never says what happens when both 'scene' and 'track'+'slot' are supplied, or that omitting all arguments is a no-op.

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