Single tool with well-structured schema and clear naming. Tool name 'get_youtube_transcript' correctly starts with action verb and reflects functionality. Input schema is complete with proper type definitions, descriptions, examples, and pattern validation. Description is adequate (56 chars) but could be more detailed regarding output format. Parameter descriptions are present and include constraints (language pattern). However, output schema is not explicitly documented, return type is declared as 'str' but the actual structure/format of the transcript is not described for the LLM. Error handling exists but lacks recovery guidance. Overall solid foundation with room for output schema documentation and error messaging improvements.

• Document output schema explicitly: 'Returns: A plain-text transcript with one caption per line. Timestamps are stripped. If captions span multiple languages, only the requested language is returned.' This enables LLMs to reason about downstream usage.
• Enhance error messages with recovery paths. Example: catch YouTubeTranscriptApi errors and return 'Transcript not available, try lang="es" or another language, or check if the video URL is correct.'
• Expand tool description from 56 to ~150-200 chars. Add: 'Extracts the full transcript of a YouTube video. Useful for summarization, citation, or content analysis. Supports multiple languages via the lang parameter. Returns plain text, one caption per line.'
• Add validation for transcript availability: before returning, check if the transcript is empty or None and raise a descriptive error.
• Consider adding a 'List available languages' discovery tool or endpoint, so agents know which language codes are valid before calling get_youtube_transcript. This prevents wasted retries with invalid language codes.

Inferred effective spec: <=2025-11-25.

• Relies on Logging (deprecated) - log to stderr or use OpenTelemetry