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YouTube RAG Server - MCP tools for video content analysis. Download and index YouTube videos for semantic search with transcript extraction, frame analysis, and multimodal embeddings.
This is a well-structured YouTube RAG MCP server with clear tool naming, comprehensive input schemas, and good parameter documentation. All 6 tools follow verb_noun naming conventions (ingest_*, get_*, query_*, list_*, delete_*). Input schemas are complete with proper JSON Schema typing. However, output schemas are not documented in the visible code, and error handling guidance is absent from descriptions. Tool descriptions are adequate (100-200 chars) but lack dependency hints and recovery guidance. The server demonstrates production-quality tool design but falls short of exceptional standards due to missing output documentation and weak error handling narratives.
Delete an indexed video and all its associated data (chunks, embeddings, artifacts).
Get the processing status of a video ingestion job.
Get source artifacts (frames, audio, video) for citations.
Download and index a YouTube video for semantic search. Extracts transcript, frames, and creates embeddings.
List indexed videos with optional filtering.
Query video content using natural language. Returns answer with timestamp citations.
Output schemas not documented. Tool descriptions do not specify what fields LLMs can expect in responses (e.g., ingest_video should document returned video_id format, get_ingestion_status should document status enum values and progress metadata, query_video should document citation structure). Without output documentation, agents cannot reliably chain tools or extract necessary data for downstream calls.
Error handling lacks recovery guidance. Descriptions do not explain what the LLM should do if a call fails (e.g., 'If video_id is invalid, call list_videos() first to find a valid ID'). Tool descriptions should include error categories (retryable, user-fixable, fatal) and next-step guidance per pattern:recovery-guide.
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-22 | C | 66 | 2026-07-28+ | v2 |
| 2026-03-09 | D | 55 | - | v1 |
delete_video lacks confirmation safety pattern. Destructive tools should document a dry-run option or require explicit confirmation to prevent agent mistakes. Current schema has 'confirm' boolean, which is good, but description does not emphasize this is a destructive operation or explain the consequences.
Minimal dependency hints. Descriptions do not guide multi-step workflows. For example, query_video should note 'Call ingest_video first if the video is not yet indexed', and get_sources should explain 'Requires citation_ids from a prior query_video call'. These dependencies are implicit but should be explicit per pattern:tool-description.
Parameter descriptions lack format and constraint guidance. For example, 'youtube_url' should clarify 'Full YouTube URL (https://youtube.com/watch?v=... or https://youtu.be/...)'. 'language_hint' should specify 'ISO 639-1 code (e.g., en, es, fr)'. 'modalities' should explain what each enum value retrieves. Current descriptions are generic per review:param-validation-rules.