Start screen recording

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

With no annotations, the description carries the full burden. It discloses the underlying mechanism (adb screenrecord), the 3-minute limit, and that it returns a recordingId for the stop tool. It omits failure conditions or file handling, but for a simple start operation this is acceptable.

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 a single sentence with a clear verb and resource, immediately stating what it does and the key constraint. It also includes the critical return value and pairing information with no filler.

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 paired start/stop recording tool, the description provides the essential context: what is recorded, the method, the time cap, and the returned ID. Since there is no output schema, the description appropriately covers the return value. Minor gaps like error behavior are acceptable at this complexity level.

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?

Both parameters are already fully documented in the input schema (100% coverage), including serial semantics and timeLimitSeconds maximum/default. The description only reinforces the time limit via 'max 3 minutes,' adding no new parameter-level detail.

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 'Start recording the device screen' with the specific method 'adb screenrecord' and a time cap. It clearly identifies the resource (device screen) and action, and the pairing with record_video_stop distinguishes it from sibling tools.

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 description explicitly names the companion tool record_video_stop, indicating this is the start of a paired workflow. It does not list exclusions or alternatives, but the context is clear since no other sibling tool initiates screen recording.

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