docs: clarify workspace vs sandbox

docs/concepts/agent-workspace.md

@@ -12,6 +12,11 @@ file tools and for workspace context. Keep it private and treat it as memory.
 This is separate from `~/.clawdbot/`, which stores config, credentials, and
 sessions.
 
+**Important:** the workspace is the **default cwd**, not a hard sandbox. Tools
+resolve relative paths against the workspace, but absolute paths can still reach
+elsewhere on the host unless sandboxing is enabled. If you need isolation, use
+[`agent.sandbox`](/gateway/sandboxing) (and/or per‑agent sandbox config).
+
 ## Default location
 
 - Default: `~/clawd`

docs/concepts/multi-agent.md

@@ -22,6 +22,11 @@ available from `~/.clawdbot/skills`. See [Skills: per-agent vs shared](/tools/sk
 
 The Gateway can host **one agent** (default) or **many agents** side-by-side.
 
+**Workspace note:** each agent’s workspace is the **default cwd**, not a hard
+sandbox. Relative paths resolve inside the workspace, but absolute paths can
+reach other host locations unless sandboxing is enabled. See
+[Sandboxing](/gateway/sandboxing).
+
 ## Paths (quick map)
 
 - Config: `~/.clawdbot/clawdbot.json` (or `CLAWDBOT_CONFIG_PATH`)