fablecut_beats

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

With no annotations, the description carries the whole burden and does so: it discloses that snapped cuts only move within half a beat, that linked stems follow, that locked clips are skipped or refused unless force:true, that a version is saved before snap/retime with a warn-and-continue fallback, and that ffmpeg must be on PATH. These are exactly the side effects, reversibility guarantees, and prerequisites an agent needs before a mutating call.

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?

Front-loaded with the core purpose and free of filler, but the body is a single dense run-on packed with nested parentheses and inline object literals (snap:{tracks}, retime:{track?, every?, from?}), which makes it hard to scan. The content earns its place; the structure does not help it.

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?

No annotations and no output schema, so the description must supply both safety and result context, and it does: it names what gets produced (BPM, beat grid, drop in timeline seconds) and covers mutation safety, failure handling, prerequisites and lock semantics. An agent can decide and call correctly from this text alone.

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 meaning beyond the schema: maxShift is half a beat, `from` defaults to the music's start and is rounded to the first beat at or after it, retime ordering is preserved and a clip whose footage runs out gets fewer beats. Defaults for every (2) and track (lowest video track with clips) are stated in prose as well.

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 specific verb and resource pair: listens to a music clip, computes BPM, a phased beat grid and the drop, then optionally applies markers/snap/retime. The purpose is unmistakable and would not be confused with fablecut_silence or fablecut_highlights, although no sibling is named to make that contrast 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?

'Without markers / snap / retime it only reports' cleanly separates the analyze mode from the edit modes, and 'The same as the Inspector's Beats section' anchors it to a known UI surface. It does not, however, say when to prefer this over sibling analysis tools such as fablecut_silence or fablecut_highlights.

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