SageThumbs 2K is a Windows shell extension / thumbnail generator, not an MCP server. The evaluation found one tool 'flv-frame' with an extremely terse description ('Extract Flash video frames for thumbnail generation'), no visible input schema, no parameter definitions, no output schema documentation, and no error handling guidance. The tool appears to be a CLI binary (st2k in src/bin/cli.rs) rather than a properly registered MCP tool with JSON schema. The codebase is a Rust Windows DLL/EXE project focused on image thumbnailing (EXR, JPEG XL, DjVu, DDS, etc.), there is no evidence of MCP server implementation, message handling, tool registration protocol, or transport layer. The single referenced tool cannot be evaluated against production MCP patterns because its definition is not visible in the source provided.

• Confirm this is intended as an MCP server. If so, implement the MCP protocol with proper message handling and tool registration.
• Define the flv-frame tool with a comprehensive JSON schema listing all input parameters, their types, descriptions, and constraints.
• Expand the tool description to 150 - 200 characters explaining: (1) what it does (extract frames from FLV videos), (2) when to use it (when user requests video frame extraction/thumbnails), (3) what it returns (e.g., array of frame data with timestamps, dimensions, format).
• Add parameter descriptions for each input: What does each parameter control? What values are valid? Is it required or optional? Are there dependencies between parameters?
• Document the output schema with field names, types, and meanings. Example: { frames: [ { timestamp_ms: number, width: number, height: number, data: string } ], duration_ms: number }.
• Add error handling with actionable messages. Example: 'Invalid FLV file: header signature not found. Ensure the file is a valid Flash video.' instead of a bare error code.
• If the tool is read-only (which the metadata suggests), document this and explain that the LLM can safely call it without side effects.