Environment variables

Each app has a set of environment variables. Your coding agent sets them with the MCP tool env, and reads their names with the MCP tool env_names. No call returns a value.

Set the variables

The MCP tool env takes the app_id and variables, a flat object of strings. It replaces the whole set: names you leave out are removed.

With the CLI, send one JSON object on standard input:

astris env --app <id>

The new values apply at the next deploy or restart.

Read the names

astris env --app <id> --names

It prints one name per line and never a value. The MCP tool env_names gives the same.

Rules

• A name starts with a letter or _, and holds only letters, digits and _.
• Each value is a string with no line break.
• A set has at most 200 names.
• The request body is at most 64 KB.

A body that breaks a rule is refused with bad_request. An account with no plan is refused with upgrade_required. The CLI refuses input that is not one JSON object and sends nothing.

Keep secrets out of your repository

Put keys and passwords in environment variables, not in your files. The pre-flight check refuses a repository with a key in it.