Watch a video

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

The annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds valuable behavioral detail beyond that: adaptive keyframe selection, tile frame numbers and timestamps, timeline alignment with a timestamped transcript, and local Whisper transcription. With no output schema present, this return-format disclosure is especially important.

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 description is two tightly packed sentences with no filler. It front-loads the core action and return format, then immediately gives the usage cue.

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 read-only tool with no output schema, the description explains both what is returned (storyboard images and aligned transcript) and how to use it ('first'). The input schema fully covers parameters, so nothing essential is missing for correct invocation.

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 100%, so the schema already documents path, start, end, budget, language, and transcript. The description's note about more frames where things change loosely relates to the budget parameter but adds no concrete syntax or defaults beyond what the schema provides. Baseline 3 is appropriate.

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 ('Watch a local video') and explains the distinctive output: storyboard keyframes plus a timestamped speech transcript. 'Use this first for any video or screen recording' implicitly distinguishes it from the sibling detail tools zoom, frame, and transcribe by positioning it as the initial overview.

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 clear usage context ('Use this first for any video or screen recording'), which tells the agent when to reach for this tool ahead of alternatives. It does not explicitly name the alternatives or state when not to use it, so it falls short of full 5-level routing guidance.

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