> ## Documentation Index > Fetch the complete documentation index at: https://docs.tokenfactory.nebius.com/llms.txt > Use this file to discover all available pages before exploring further. # env - Manage session environment variables Manage session-level environment variables. Variables set with `env` are applied to every `contree run` automatically. Per-run `-e` flags override session env vars with the same key. ## Examples ```bash theme={null} # Set PATH after installing tools contree env PATH=/root/.cargo/bin:/usr/local/bin:/usr/bin:/bin:/sbin # Set multiple variables contree env DEBUG=1 DB_HOST=localhost # List current session env contree env # Unset variables contree env -U PATH contree env -U DEBUG DB_HOST # Per-run -e overrides session env contree run -e DEBUG=0 -- ./app ``` ## Help output

\$ contree env --help

usage: contree env \[-h] \[-U] \[KEY=VALUE ...]

Manage session environment variables.

Session env vars are applied to every \`contree run\` automatically.
Per-run \`-e\` flags override session env vars with the same key.

positional arguments:
  KEY=VALUE           Environment variables to set (or keys to delete with -d)

options:
  -h, --help          show this help message and exit
  -U, --delete, --rm  Unset the specified environment variables

examples:
  contree env                                  list session env vars
  contree env PATH=/root/.cargo/bin:\$PATH      set PATH
  contree env DEBUG=1 DB\_HOST=localhost         set multiple
  contree env -U PATH                          unset PATH
  contree env -U PATH DEBUG                    unset multiple

agent note:
  Before using this command in an automated workflow, read:
    contree agent

## Behavior Session env vars are stored in SQLite per session. They persist across terminal restarts (when using `-S` or `CONTREE_SESSION`). When `contree run` builds the payload, it merges: 1. Session env vars (base) 2. Per-run `-e` flags (override) Deleting a session (`session delete`) removes its env vars. Values with `=` in them work correctly — only the first `=` is the separator: `contree env CMD=a=b=c` sets `CMD` to `a=b=c`.