ui_set_snap_mode

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

No annotations are provided, so the description carries the behavioral burden. It discloses that this is a global, persistent setting and warns to restore the previous mode afterward, which is important side-effect information. It does not mention error handling or return values, but for a simple setter this is acceptable.

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?

Two compact sentences with no filler. The main action and accepted value forms are front-loaded, and the usage timing/restore guidance is included without redundancy.

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 single-parameter setter with no output schema and no annotations, the description supplies the essential usage context, accepted values, and a warning about global state. It could additionally point to ui_get_snap_mode for capturing the previous value, but the instruction to restore is still clear.

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?

The input schema only says 'mode' is a required string with 0% description coverage, so the description must compensate. It does so by listing concrete accepted values ('bar', 'beat', 'half_beat', 'step', 'line', 'cell', 'none', ...) and the alternative numeric midi.Snap_* form. This is enough for an agent to construct a valid argument, though not an exhaustive enumeration.

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 uses a specific verb ('set') and resource ('global snap mode'), immediately distinguishing this from the sibling reader ui_get_snap_mode. It also enumerates accepted forms of the mode value, removing ambiguity about what the tool operates on.

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 clear operational context: set this before GUI clip placement/moves in the playlist so clicks land on the grid, and restore the previous mode afterward. It does not explicitly name alternatives or when not to use it, but the call-site guidance is concrete and actionable.

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