Select segments

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

Annotations already declare this is a non-read-only, non-destructive, non-open-world mutation, so the safety bar is lower. The description usefully adds the downstream consequence that only selected segments are exported, but it says nothing about how selection state is affected per mode, whether prior selection is discarded, or what happens when there is no current segment or playhead.

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 short sentences with no filler, and the core action is stated first with the export consequence immediately after. Nothing is repeated or wasted.

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 tool whose only input is a six-value behavioral enum, the definition is incomplete: an agent cannot tell what "toggle_current" or "at_playhead" will do to the existing selection, which is the crux of invoking it correctly. No output schema exists, but the missing mode semantics are the real gap rather than return values.

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% and the single parameter is an enum of six non-obvious values (only_current, toggle_current, at_playhead, invert, all, none). The description explains none of these modes, leaving the most decision-relevant semantics entirely undocumented in both schema and text.

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 gives a specific verb+resource ("changes which segments are selected") that is clearly about selection state, not segment boundaries or content. It does not differentiate itself from siblings like set_segments or add_segment, so an agent must infer that this tool operates on the selection set rather than editing segments themselves.

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?

There is no explicit when-to-use guidance, no prerequisites, and no named alternative. The sentence "Only selected segments are exported" hints at why selection matters (as a pre-export step) but never states the condition under which an agent should call this versus set_segments.

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