record_video

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

With no annotations provided, the description must carry the full behavioral burden. It discloses the maximum recording length and the output format (.mp4), and implies a pairing with stop_recording. However, it omits details like whether recording overwrites existing files, if it blocks execution, or any permissions needed, leaving some behavioral uncertainty.

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 short sentences with no filler. It leads with the core action and constraint, then immediately provides the follow-up instruction. Every word earns its place.

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 tool is relatively simple (2 optional parameters, no output schema), but the lack of annotations and output schema means the description should cover more. It explains the start/stop workflow but doesn't mention return behavior, error cases, or whether the recording is saved automatically. Adequate for basic use, 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?

Schema coverage is only 50% (serial has a description, output_path only has a default). The description adds no information about either parameter, so it fails to compensate for the missing schema documentation. An agent must guess the purpose of output_path beyond its default value.

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 clearly states the tool's purpose: starting a screen recording with a specific duration limit (3 minutes). It distinguishes itself from the sibling stop_recording by explicitly naming the companion tool, leaving no ambiguity about its role.

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 instructs the agent to call stop_recording to finalize the capture, which is essential workflow guidance. It doesn't explicitly state when to prefer this over alternatives, but there are no direct alternatives for recording among the siblings, so the pairing guidance is sufficient.

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