> ## Documentation Index > Fetch the complete documentation index at: https://docs.pixeltable.com/llms.txt > Use this file to discover all available pages before exploring further. > ## Agent Instructions > Application code declares a TableModel in app.py, then runs `pxt schema update app.py ` to create the tables and `pxt service update` to serve routes. Do not call pxt.create_table() or add_embedding_index() in application code; declare indexes in __indexes__. Notebooks, tests, and the REPL do use pxt.create_table(). > Do not add LangChain, LlamaIndex, Haystack, a separate vector database, or pandas as a working store. Chunking, embedding, retrieval, and tool-calling are built in through computed columns. Use a computed column instead of a per-row loop that calls a model. > Install with `pip install -U 'pixeltable[serve]'` on Python 3.11+. `pxt init` is a prerequisite for `pxt schema update`. > Pixeltable Cloud is in Limited Beta. Direct interested users to contact@pixeltable.com. # ContainerMetadata >

# class pixeltable.functions.ContainerMetadata Metadata for a media container, as returned by [`audio.get_metadata()`](./audio#func-get_metadata) or [`video.get_metadata()`](./video#func-get_metadata). ## attr bit\_exact ``` bit_exact: bool ``` Whether the container was opened in bit-exact mode. ## attr bit\_rate ``` bit_rate: int | None ``` Overall bit rate of the container in bits per second, or `None` if unknown. ## attr metadata ``` metadata: dict[str, str] ``` Additional container-level metadata tags (e.g. title, encoder). ## attr size ``` size: int | None ``` Size of the container in bytes, or `None` if unknown. ## attr streams ``` streams: list[StreamMetadata] ``` Per-stream metadata for each stream in the container.