Logs

The Docker Compose stack includes OpenObserve, and the server ships every log line to it as well as to stderr.

Opening the logs UI

Open http://<host>:5080 and sign in as nexul@nexul.local, with the password you chose when running the install script — or the one it generated for you, printed at the end of the install and saved to .env as NEXUL_LOGS_PASSWORD. Both the email and password can be changed later inside OpenObserve itself.

Logs land in the nexul stream of the default org.

Environment variables

Variable	What it sets
NEXUL_LOGS_EMAIL	The OpenObserve root user’s email
NEXUL_LOGS_PASSWORD	The OpenObserve root user’s password
NEXUL_LOGS_TOKEN	The ingest token the server uses to ship logs

All three are generated into .env by install.sh / install.ps1 on first run and reused on every re-run.

Querying logs through MCP

OpenObserve ships its own MCP server, so an agent can search your logs directly. It authenticates with the UI password, not the ingest token. To add it in Claude Code:

claude mcp add --transport http nexul-logs http://<host>:5080/api/default/mcp \
  --header "Authorization: Basic $(echo -n "$NEXUL_LOGS_EMAIL:$NEXUL_LOGS_PASSWORD" | base64 -w0)"

Single-binary installs

A single-binary install has no bundled OpenObserve. Point it at any OTLP/HTTP backend instead:

Variable	What it sets
NEXUL_OTLP_ENDPOINT	The backend’s base URL (/v1/logs is appended automatically)
NEXUL_OTLP_USER	Basic auth username for the backend
NEXUL_OTLP_TOKEN	Basic auth token for the backend

Leave NEXUL_OTLP_ENDPOINT unset to keep logs on stderr only.