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

Annotations give readOnlyHint=false, idempotentHint=true, destructiveHint=false, and the description adds substantial context beyond that: the write is free, the prior duration is stashed in clip.metadata.dauer_vorher giving a single undo step that a second differing run overwrites, and there is no history. It also discloses that a refusal to snap is a valid result, not an error, and clarifies that 'gerastet: true' only proves snapping ran while raster.getroffen shows whether it landed.

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 core action is front-loaded and no sentence is filler — the dense error-code list and the dauer_vorher/undo caveat are all decision-relevant. It is nevertheless a long, single-block description; a short bulleted split of the refusal codes would have improved scanability without losing content.

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?

With no output schema, the description carries the return contract itself: it names the fields to inspect (gerastet, raster.grund, raster.getroffen of raster.von, and geklemmt) and explains what each implies. Prerequisite ordering and the non-error semantics of a failed snap are fully covered.

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 100%, so the baseline is 3, but the description adds real value by tying parameters to outcomes: passing toleranz_s 0 yields 'toleranz_null' and disables snapping, while trotz_unsicherem_tempo overrides the 'tempo_unverlaesslich' refusal and sets raster.unsicheres_tempo_uebergangen. This gives the agent a reason to set each optional parameter rather than just their formats.

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?

Names a precise verb and resource — recomputes clip durations from the cutting preset and snaps cut points to the measured beat grid — and explicitly scopes what it does not do (clip count never changes). It is clearly separable from siblings like lab_beatgrid and lab_bind_audio, which it names as prerequisites.

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?

Gives explicit when-to-use, when-not-to-use, and prerequisite routing: 'nicht_gemessen' → run lab_beatgrid first, 'keine_musikspur'/'musikspur_nicht_aufgeloest' → run lab_bind_audio first, and 'rhythmus_ohne_raster' → the preset is 'frei'/'atmend' so not snapping is intended. The trotz_unsicherem_tempo override is also explained as a deliberate choice rather than a default.

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