media-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 states the action ('extract frames') and default behaviors (e.g., output directory defaults), but lacks critical details: whether it overwrites existing files, requires specific permissions, handles errors (e.g., invalid paths), has rate limits, or what the output schema returns. For a tool with 5 parameters and no annotations, this is a significant gap in transparency.

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 appropriately sized and front-loaded: the first sentence states the core purpose, followed by a structured 'Args:' section listing parameters with concise explanations. Every sentence earns its place by providing essential information without redundancy. The formatting enhances readability, making it easy to scan.

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 complexity (5 parameters, no annotations, but has output schema), the description is partially complete. It excels in parameter semantics but lacks behavioral context (e.g., error handling, side effects). The output schema exists, so the description needn't explain return values, but it should cover more operational aspects. For a video processing tool, this leaves gaps in understanding how it behaves in practice.

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 description coverage is 0%, so the description must fully compensate. It successfully adds meaning beyond the schema by explaining all 5 parameters: 'path' (absolute path to video), 'interval_seconds' (time between frames), 'max_frames' (maximum to extract), 'output_dir' (directory to save, with default), and 'format' (image format with options). This provides clear semantics, defaults, and constraints not in the schema.

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: 'Extract frames from a video at regular intervals.' This specifies the verb ('extract'), resource ('frames from a video'), and method ('at regular intervals'). It distinguishes from siblings like 'convert_video' or 'get_video_info' by focusing on frame extraction rather than format conversion or metadata retrieval. However, it doesn't explicitly contrast with all siblings (e.g., 'create_thumbnail' might also extract frames).

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 prerequisites (e.g., video file accessibility), compare to siblings like 'create_thumbnail' for single-frame extraction, or specify use cases (e.g., for analysis vs. preview). The only implied context is video frame extraction, but no explicit when/when-not rules are given.

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