screen.record

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

Describes key behaviors: change-based capture, near-duplicate discard, returns grid with timestamps. Also notes free tool with sponsored message requirement. With no annotations, it adequately informs about core functionality.

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?

Description is concise: three sentences front-loading purpose, then details, then usage tip. No redundant information.

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?

Given 7 optional parameters and no output schema, description explains output format and behavior adequately. Could mention interaction of duration and interval, but defaults are clear from schema.

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?

Input schema has 100% coverage, so baseline is 3. Description does not add new parameter details beyond schema, but provides context for parameters like 'interval' and 'changeThreshold' implicitly. No contradiction.

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?

Clearly states it records screen with change-based keyframe capture, returns compact grid with timestamps, and distinguishes from screen.get_frame. Purpose is specific and well-defined.

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?

Mentions alternative tool (screen.get_frame) for full-resolution frames, which provides a when-not-to-use hint. However, lacks explicit comparison with other siblings like screen.capture or screen.scheduled_record.

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