Initial commit: OpenClaw Skill Collection

6 custom skills (assign-task, dispatch-webhook, daily-briefing,
task-capture, qmd-brain, tts-voice) with technical documentation.
Compatible with Claude Code, OpenClaw, Codex CLI, and OpenCode.

openclaw-knowhow-skill/docs/infrastructure/environment.md

@@ -0,0 +1,38 @@
+# Environment Variables Documentation
+
+OpenClaw manages environment variables through a hierarchical system that respects existing values without overriding them.
+
+## Loading Priority
+
+The system follows a specific precedence order from highest to lowest priority:
+
+1. **Process environment** - Variables already present in the parent shell/daemon
+2. **Local `.env` file** - Located in the current working directory
+3. **Global `.env` file** - Found at `~/.openclaw/.env`
+4. **Configuration file settings** - The `env` block in `~/.openclaw/openclaw.json`
+5. **Shell environment import** - Optional login-shell variables when enabled
+
+## Configuration Methods
+
+You can define variables directly within the config file using two equivalent approaches:
+
+```json5
+{
+  env: {
+    OPENROUTER_API_KEY: "sk-or-...",
+    vars: {
+      GROQ_API_KEY: "gsk-...",
+    },
+  },
+}
+```
+
+Shell environment import capability allows the system to run your login shell and import only missing expected keys.
+
+## Variable Substitution
+
+Config files support variable references using `${VAR_NAME}` syntax within string values, enabling dynamic configuration based on environment settings.
+
+## Related Resources
+
+The documentation links to gateway configuration guides, FAQ materials about env var loading, and models overview pages for additional context.