Set segments

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

Annotations already declare a non-readonly, non-destructive operation, and the description goes further by disclosing concrete side effects: a project file is written next to the media, an existing project file is renamed to a .bak backup, and the currently open file is closed first. That is meaningful behavioral context beyond the annotations, and it is consistent with destructiveHint=false since nothing is deleted. It stops short of the maximum because error behavior and what happens to unsaved state in the closed file are unaddressed.

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 sentences, front-loaded with the action and its outcome, followed by file-system side effects and then the sibling routing. No sentence is filler and the measurement of scope comes before the preference hint.

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 only two required parameters, no output schema, and annotations carrying the safety profile, the definition covers what an agent needs: what it does, what it writes on disk, what it closes, and when to prefer it. Remaining gaps (ordering assumptions within the segments array, behavior on invalid paths) are minor.

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 50%; the description compensates by making the key semantic explicit — 'an exact list of segments ... in one step' signals that this replaces the segment set rather than appending, which is the central distinction from add_segment. It does not explain the undocumented name/selected fields or confirm that the path is the currently-open media file.

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 states a specific verb and resource ('Loads an exact list of segments for a media file') plus the effect ('opens it in LosslessCut'), and it distinguishes itself from the sibling add_segment. An agent can tell immediately that this is a bulk replace-style operation rather than an incremental append.

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 an explicit alternative and the condition that selects it: 'Prefer this over add_segment for precise cuts.' No when-not guidance or exclusion against other segment-related siblings (set_cut_points, select_segments) is offered, so it falls short of a full routing rule.

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