Watch a video segment

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds real information beyond them: the speech pipeline falls back from captions to local Whisper transcription and the response states which source was used, which matters for trust in the result. It omits the practical cost of transcription (latency) for long segments.

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?

A single front-loaded sentence that leads with the value proposition and then lists the outputs. Dense but every clause carries information; only the marketing-ish 'fastest way' framing is slightly expendable.

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 seven optional parameters and no output schema, the description carries the return-value burden and does so reasonably: it names the three payloads and the source annotation. Missing only the shape/limits of the timeline and what happens when no audio or captions exist.

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% with per-parameter descriptions, defaults and an enum for 'speech', so the schema already does the heavy lifting. The description only adds the framing of 'segment' and 'timeline', which the schema conveys via start/duration/frames; baseline 3 applies.

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 specific verb and resource ('watch a video segment') and enumerates the three things returned: video info, a storyboard, and a speech timeline. It is clear this is a composite read that aggregates what siblings like video_storyboard, video_captions and video_transcribe would otherwise provide, though it never names those siblings explicitly.

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 fastest way to understand a video: in one call...' implies when to use it (a one-shot overview instead of several granular calls), but there is no explicit when-not, no named alternative, and no guidance on when to prefer the dedicated storyboard/caption/transcribe tools instead.

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