previewapk_record_start

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

No annotations are provided, so the description carries the full behavioral burden. It usefully discloses the 180-second cap and automatic stop/save on session end or reboot, but it does not mention permissions, whether multiple recordings can coexist, where recordings are stored, or how device selection works.

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 compact sentences, front-loaded with the action and cap, followed by the stop/download lifecycle and auto-save behavior. There is no wasted wording.

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?

The description covers the recording lifecycle and key constraints, which is useful given the lack of annotations and output schema. However, it does not resolve device selection or the optional name behavior, so it is adequate but not fully complete.

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?

The schema documents only the name parameter, and the description adds no meaning for it beyond the existing label description. The device parameter is undocumented in both the schema and the description, including whether it is optional or which device is used by default, leaving a meaningful gap for a two-parameter tool.

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: start recording the device screen to an MP4. It also names the recording cap and distinguishes the lifecycle from previewapk_record_stop and previewapk_record_download, so the tool is easy to identify among siblings.

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?

Clearly explains the lifecycle: start here, then stop with previewapk_record_stop, then download with previewapk_record_download. It does not explicitly compare against previewapk_screenshot or previewapk_observe for still-image capture, so it is strong but not fully exclusionary.

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