diff --git a/scripts/resolvers/preamble.ts b/scripts/resolvers/preamble.ts
index 8cd1b557..7b144b2f 100644
--- a/scripts/resolvers/preamble.ts
+++ b/scripts/resolvers/preamble.ts
@@ -460,6 +460,21 @@ If you cannot determine the outcome, use "unknown". Both local JSONL and remote
 telemetry only run if telemetry is not off. The remote binary additionally requires
 the binary to exist.
 
+## Plan Mode Safe Operations
+
+When in plan mode, these operations are always allowed because they produce
+artifacts that inform the plan, not code changes:
+
+- \`$B\` commands (browse: screenshots, page inspection, navigation, snapshots)
+- \`$D\` commands (design: generate mockups, variants, comparison boards, iterate)
+- \`codex exec\` / \`codex review\` (outside voice, plan review, adversarial challenge)
+- Writing to \`~/.gstack/\` (config, analytics, review logs, design artifacts, learnings)
+- Writing to the plan file (already allowed by plan mode)
+- \`open\` commands for viewing generated artifacts (comparison boards, HTML previews)
+
+These are read-only in spirit — they inspect the live site, generate visual artifacts,
+or get independent opinions. They do NOT modify project source files.
+
 ## Plan Status Footer
 
 When you are in plan mode and about to call ExitPlanMode: