Lists all available columns and their metadata.

Returns metadata for all available report columns including their key (API name), human-readable label, data type, and capabilities.

Purpose

This is the runtime discovery mechanism for building valid report queries. Call this endpoint at startup to discover:

• All valid groupBy dimensions — filter the response for canGroupBy: true.
• All valid column (metric) values — filter for canGroupBy: false.
• Human-readable display labels for column headers.
• Column data types for correct formatting.

Bootstrap sequence

For AI/programmatic consumers, the recommended startup sequence is:

1. Authenticate (POST /auth/access/session)
2. Call GET /column/info — discover valid groupBy values and built-in columns
3. Call GET /custom-conversions — discover account-specific conversion types
4. Call GET /custom-columns — discover user-defined derived metrics
5. Call GET /traffic-source — discover custom variable name mappings per source
6. Now you can build valid report queries with complete column sets.

Response fields per column

• key: the column name to use in the 'column' and 'groupBy' query parameters.
• label: human-readable display name.
• type: data type (string, number, decimal, monetary, percentage, date_time, boolean).
• canGroupBy: if true, this column can be used as a groupBy dimension.
• canBeRestricted: if true, this column can be used in filter conditions.