Environment

Variable	Used by	Default	Notes
`DATABASE_URL`	Server, CLI `start`	none	Required for direct server startup. When unset, CLI `start` uses Docker Postgres.
`PORT`	Direct server startup	`7373`	CLI `start` uses `--port`; direct `startServer()` reads `PORT`.
`ISPLAY_ARTIFACTS_DIR`	Server	`.isplay/artifacts`	Root for JSON artifact payload files.
`ISPLAY_API_URL`	CLI, API client, SDK, adapters	`http://127.0.0.1:7373`	Export it in every shell or process that talks to the API.
`ISPLAY_PROJECT_ID`	CLI, SDK `getClient()`	none	Used when `--project` is omitted or `getClient()` lazy-initializes.
`USER`	CLI fixtures	OS user	Stored as fixture author by `fixtures add`.

Recommended Local Shell

export ISPLAY_API_URL=http://127.0.0.1:7373
export ISPLAY_PROJECT_ID=project_...

export DATABASE_URL=postgres://...
export PORT=7373
export ISPLAY_ARTIFACTS_DIR=/var/lib/isplay/artifacts

npx isplay doctor
npx isplay health

If the CLI works in one terminal but not another, compare ISPLAY_API_URL and ISPLAY_PROJECT_ID.