diff --git a/README.md b/README.md
index 0b082f4ee..29d49a6a5 100644
--- a/README.md
+++ b/README.md
@@ -177,6 +177,13 @@ Produces:
 
 Each phase breaks into 2-3 atomic tasks. Each task runs in a fresh subagent context — 200k tokens purely for implementation, zero degradation.
 
+**For multi-plan phases:**
+```
+/gsd:execute-phase 1   # Run all plans in parallel, "walk away" execution
+```
+
+Use `/gsd:execute-plan` for interactive single-plan execution with checkpoints. Use `/gsd:execute-phase` when you have multiple plans and want parallel "walk away" automation.
+
 ### 4. Ship and iterate
 
 ```
@@ -316,7 +323,8 @@ You're never locked in. The system adapts.
 | `/gsd:create-roadmap` | Create roadmap and state tracking |
 | `/gsd:map-codebase` | Map existing codebase for brownfield projects |
 | `/gsd:plan-phase [N]` | Generate task plans for phase |
-| `/gsd:execute-plan` | Run plan via subagent |
+| `/gsd:execute-plan` | Run single plan via subagent |
+| `/gsd:execute-phase <N>` | Execute all plans in phase N with parallel agents |
 | `/gsd:progress` | Where am I? What's next? |
 | `/gsd:verify-work [N]` | User acceptance test of phase or plan ¹ |
 | `/gsd:plan-fix [plan]` | Plan fixes for UAT issues from verify-work |
diff --git a/commands/gsd/help.md b/commands/gsd/help.md
index 2b6fafefe..8352e68ef 100644
--- a/commands/gsd/help.md
+++ b/commands/gsd/help.md
@@ -107,15 +107,29 @@ Result: Creates `.planning/phases/01-foundation/01-01-PLAN.md`
 ### Execution
 
 **`/gsd:execute-plan <path>`**
-Execute a PLAN.md file directly.
+Execute a single PLAN.md file.
 
 - Runs plan tasks sequentially
 - Creates SUMMARY.md after completion
 - Updates STATE.md with accumulated context
-- Fast execution without loading full skill context
+- Use for interactive execution with checkpoints
 
 Usage: `/gsd:execute-plan .planning/phases/01-foundation/01-01-PLAN.md`
 
+**`/gsd:execute-phase <phase-number>`**
+Execute all unexecuted plans in a phase with parallel background agents.
+
+- Analyzes plan dependencies and spawns independent plans concurrently
+- Use when phase has 2+ plans and you want "walk away" execution
+- Respects max_concurrent_agents from config.json
+
+Usage: `/gsd:execute-phase 5`
+
+Options (via `.planning/config.json` parallelization section):
+- `max_concurrent_agents`: Limit parallel agents (default: 3)
+- `skip_checkpoints`: Skip human checkpoints in background (default: true)
+- `min_plans_for_parallel`: Minimum plans to trigger parallelization (default: 2)
+
 ### Roadmap Management
 
 **`/gsd:add-phase <description>`**