Video Screenshot MCP

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It describes what information is returned (duration, resolution, frame rate) but doesn't cover important behavioral aspects such as error handling (e.g., what happens if the video file doesn't exist), performance characteristics, or whether it requires specific permissions. This is a significant gap for a tool with no annotation coverage.

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, efficient sentence that directly states the tool's purpose with relevant examples. It's front-loaded with the main action and includes no unnecessary information, making it highly concise and well-structured.

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 the tool's low complexity (1 parameter, no output schema, no annotations), the description is minimally adequate. It covers the basic purpose but lacks details on behavioral traits and usage guidelines. With no output schema, it doesn't explain return values beyond the examples provided, leaving gaps in completeness for effective agent use.

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 input schema has 100% description coverage (the 'videoPath' parameter is documented as '视频文件路径' - video file path), so the schema does the heavy lifting. The description doesn't add any parameter-specific details beyond what's in the schema, such as format examples or constraints. Baseline 3 is appropriate when schema coverage is high.

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: '获取视频文件的详细信息，包括时长、分辨率、帧率等' (Get detailed information about video files, including duration, resolution, frame rate, etc.). It specifies the verb ('获取' - get) and resource ('视频文件' - video files) with examples of information returned. However, it doesn't differentiate from sibling tools like 'validate_video' which might have overlapping functionality.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like 'validate_video' (which might check video validity rather than retrieve metadata) or explain scenarios where this tool is preferred. The usage context is implied but not explicitly stated.

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