> ## Documentation Index
> Fetch the complete documentation index at: https://schemabrain.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# describe_column

> Drill into one column with its bidirectional FK graph.

<Note>
  **Layer:** Physical schema
</Note>

Drill into one column. Returns its structural metadata + LLM description +
the join graph it participates in:

* `outgoing_foreign_keys`: this column joins out to where
* `incoming_foreign_keys`: which other tables reference this column

The bidirectional FK graph is the killer feature here — primary keys'
incoming FKs describe the entire join surface in one tool call.

Pass `qualified_name` as `schema.table.column` — e.g.
`"public.orders.user_id"`.