> ## 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 puts a TableModel in app.py, then runs `pxt schema update app.py my_app` to create the tables and `pxt service update app.py my_app` to start HTTP. The last argument can be a Cloud URL such as `pxt://org:db`. Do not call pxt.create_table() or add_embedding_index() in application code; put 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. # VersionMetadata > View Source on GitHub # class  pixeltable.VersionMetadata Metadata for a specific version of a Pixeltable table. ## attr  change\_type ``` change_type: Literal['data', 'schema'] ``` The type of table transformation that this version represents (`'data'` or `'schema'`). ## attr  created\_at ``` created_at: datetime.datetime ``` The timestamp when this version was created. ## attr  deletes ``` deletes: int ``` The number of rows deleted in this version. ## attr  errors ``` errors: int ``` The number of errors encountered during this version. ## attr  inserts ``` inserts: int ``` The number of rows inserted in this version. ## attr  schema\_change ``` schema_change: str | None ``` A description of the schema change that occurred in this version, if any. ## attr  updates ``` updates: int ``` The number of rows updated in this version. ## attr  user ``` user: str | None ``` The user who created this version, if defined. ## attr  version ``` version: int ``` The version number. This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.