Search YouTube globally for videos, channels, or playlists on any topic. Returns up to 50 results with metadata. Use this for topic-based discovery when the user has not specified a channel — for searching within a known channel use search_channel_videos instead.

Fetch consolidated YouTube video metadata with numeric types — title, channel, duration, view count, publish date, thumbnail, description, captions availability. Does NOT include the transcript itself; call fetch_transcript or transcribe_video for that. Cheap, fast, free.

Fetch the existing official transcript (subtitles/captions) of a YouTube video, with per-segment timestamps and language detected. Errors with NO_CAPTIONS if the video has no captions — fall back to transcribe_video in that case to generate one with AI ASR. This call is free.

Start an asynchronous AI ASR (Whisper) transcription of a YouTube video. Returns immediately with a task_id and estimated_wait_seconds; the actual transcription runs in the background. Poll status with get_asr_task. Use this when fetch_transcript returned NO_CAPTIONS or when the video has no captions. Costs 5 credits, debited only on successful completion.

Poll the status of an ASR task created by transcribe_video. Returns one of queued, downloading, transcribing, finalizing, done, or failed. When status is done, includes the full transcript with timestamps. Recommended polling interval: 3-5 seconds. Free — does not consume credits.

Resolve a YouTube @handle, channel URL, video URL, or raw channel ID into canonical channel info (channel ID, name, handle, subscriber count, video count, avatar). Call this first when you only have a handle or URL but need a channel ID for the other channel-scoped tools.

List all videos from a YouTube channel ordered by publish date (newest first), with pagination. Returns up to 30 per page plus a continuation token if more results exist. For just the most recent handful, prefer get_channel_latest_videos for simplicity.

Get the most recent videos from a YouTube channel — convenience wrapper over list_channel_videos with no pagination. Best for 'what did this creator publish recently?' style queries.

Search for specific videos within a single YouTube channel. Restricts results to the given channel. Use after resolve_channel if starting from a handle. Useful for 'find Karpathy's video about backpropagation' style queries.

List videos in a YouTube playlist in order, with pagination. Returns video metadata and position within the playlist. Works for any public or unlisted playlist exposed by its URL/ID.

Save a video to the authenticated user's Library. Three modes via kind: 'asr' bookmarks the video and flips has_asr (use after a successful transcribe_video → fetch_transcript flow); 'summary' uploads a summary blob; 'both' does both at once. Idempotent: saving the same video twice updates the existing entry.

List videos the user has saved to their Library (transcripts + summaries). Supports substring search on title/author, favorites filter, and pagination. Returns recently saved items first. Scoped to the calling user's data only.

Read a saved Library item with its transcript and AI summary inline (when available). Use after list_library to fetch the full content the user saved. Free.