fix: keep core tools when allowlist is plugin-only

docs/plugins/agent-tools.md

@@ -82,6 +82,8 @@ Enable optional tools in `agents.list[].tools.allow` (or global `tools.allow`):
 ```
 
 Other config knobs that affect tool availability:
+- Allowlists that only name plugin tools are treated as plugin opt-ins; core tools remain
+  enabled unless you also include core tools or groups in the allowlist.
 - `tools.profile` / `agents.list[].tools.profile` (base allowlist)
 - `tools.byProvider` / `agents.list[].tools.byProvider` (provider‑specific allow/deny)
 - `tools.sandbox.tools.*` (sandbox tool policy when sandboxed)

docs/tools/lobster.md

@@ -121,6 +121,10 @@ Lobster is an **optional** plugin tool (not enabled by default). Allow it per ag
 
 You can also allow it globally with `tools.allow` if every agent should see it.
 
+Note: allowlists are opt-in for optional plugins. If your allowlist only names
+plugin tools (like `lobster`), Clawdbot keeps core tools enabled. To restrict core
+tools, include the core tools or groups you want in the allowlist too.
+
 ## Example: Email triage
 
 Without Lobster: