diff --git a/.env.example b/.env.example
index d912938aa..4839b6741 100644
--- a/.env.example
+++ b/.env.example
@@ -15,6 +15,10 @@ NODE_ENV=production
 # separately via BACKEND_PORT (see the Ports section) — leave this at 4000.
 PORT=4000
 
+# Graceful shutdown deadline in milliseconds. On SIGTERM/SIGINT the backend
+# stops accepting requests and exits once this elapses. Default 20000.
+# SHUTDOWN_TIMEOUT_MS=20000
+
 # Compose project name — also the prefix for the network, volumes and container
 # names (amcp-app, amcp-postgres, …). Override it to run more than one
 # AnythingMCP stack on the same host without name collisions.
@@ -46,6 +50,12 @@ ENCRYPTION_KEY=change-me-in-production-exactly-32
 # independently from JWT_SECRET).
 # COOKIE_SECRET=change-me-in-production-min-32-chars
 
+# HMAC secret for identifier hashes in the knowledge graph. Falls back to
+# ENCRYPTION_KEY, then JWT_SECRET, then a built-in development value. Set it
+# explicitly in production rather than relying on that fallback chain:
+# changing the effective secret later changes every stored hash.
+# KG_HASH_SECRET=change-me-in-production-min-32-chars
+
 # Postgres Row-Level Security — database-enforced tenant isolation on top of the
 # app-layer checks. OFF by default; this is a staged rollout, not a flip switch:
 # the DATABASE_URL role must be NON-superuser, query call sites must run through
@@ -67,6 +77,20 @@ CORS_ORIGIN=http://localhost:3000
 # All other users must be invited by an admin. Set to true to allow open registration.
 ALLOW_OPEN_REGISTRATION=false
 
+# ── Email (SMTP, optional) ───────────────────────────────────────────────────
+# Instance-wide SMTP for invitations, verification and password reset emails.
+# Used only when no SMTP server is configured in the admin Settings page.
+# SMTP_PORT defaults to 587. SMTP_SECURE=true uses implicit TLS; port 465
+# enables it automatically. SMTP_FROM defaults to "AnythingMCP <SMTP_USER>".
+# SMTP_REPLY_TO sets where replies go when SMTP_FROM is a noreply address.
+# SMTP_HOST=smtp.example.com
+# SMTP_PORT=587
+# SMTP_SECURE=false
+# SMTP_USER=
+# SMTP_PASS=
+# SMTP_FROM="AnythingMCP <noreply@example.com>"
+# SMTP_REPLY_TO=
+
 # ── Catalog auto-sync ─────────────────────────────────────────────────────────
 # On startup, automatically applies "safe" catalog updates (tool
 # description/parameter fixes — no endpoint or tool add/remove changes) to
@@ -137,6 +161,14 @@ MCP_RATE_LIMIT_PER_MINUTE=60
 # MCP_SESSION_IDLE_MIN=30
 # MCP_MAX_SESSIONS=500
 
+# ── Knowledge Graph (optional) ───────────────────────────────────────────────
+# Set KG_MCP_TOOL=off to hide the kg_how_to_obtain tool and the knowledge-graph
+# resource from MCP clients on every workspace.
+# KG_MCP_TOOL=
+# Per-workspace cooldown in seconds between automatic graph ingests triggered
+# by tool calls. Default 45.
+# KG_OBSERVE_COOLDOWN_SEC=45
+
 # ── Knowledge Graph — AI features (optional) ─────────────────────────────────
 # Global switch + API key for LLM graph enrichment / skill generation. Without
 # these, all AI features stay off regardless of per-workspace toggles.
@@ -201,6 +233,11 @@ MCP_RATE_LIMIT_PER_MINUTE=60
 # COST_PER_CALL_MICROS=0
 # COST_PER_PROXY_CALL_MICROS=0
 
+# ── Sentry tracing (optional) ────────────────────────────────────────────────
+# Only used when SENTRY_DSN is set. Trace sample rate (0 to 1) for MCP calls;
+# defaults to a fifth of SENTRY_TRACES_SAMPLE_RATE, which covers HTTP requests.
+# SENTRY_MCP_TRACES_SAMPLE_RATE=
+
 # ── Operator Analytics (cloud build only — leave empty on self-hosted) ──────
 # Loads Google Tag Manager + a Consent Mode v2 cookie banner. Self-hosted
 # builds must leave both empty so no tracking is shipped to community users.
diff --git a/docs/deployment.md b/docs/deployment.md
index d6f40cb93..67a9bfeba 100644
--- a/docs/deployment.md
+++ b/docs/deployment.md
@@ -366,6 +366,13 @@ curl -s http://localhost:4000/api/mcp-api-keys \
 | `MCP_API_KEY` | No | API key for legacy MCP auth |
 | `SERVER_URL` | No | Server URL for OAuth2 metadata (default: `http://localhost:4000`) |
 | `MCP_RATE_LIMIT_PER_MINUTE` | No | Rate limit per client (default: 60) |
+| `SMTP_HOST` | No | SMTP server for instance emails; used when no SMTP is configured in the admin Settings page |
+| `SMTP_PORT` | No | SMTP port (default: 587) |
+| `SMTP_SECURE` | No | `true` for implicit TLS (default: `false`; always on for port 465) |
+| `SMTP_USER` | No | SMTP username |
+| `SMTP_PASS` | No | SMTP password |
+| `SMTP_FROM` | No | Sender address (default: `AnythingMCP <SMTP_USER>`) |
+| `SMTP_REPLY_TO` | No | Reply-To address, for when `SMTP_FROM` is a noreply address |
 | `COMPOSE_PROFILES` | No | Set to `proxy` to enable Caddy reverse proxy |
 | `DOMAIN` | No | Domain for Caddy SSL certificate (e.g., `example.com`) |
 | `ACME_EMAIL` | No | Email for Let's Encrypt certificate notifications |