docs: add /gsd:status to README and help

New command for monitoring background agents from parallel execution.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

README.md

@@ -325,6 +325,7 @@ You're never locked in. The system adapts.
 | `/gsd:plan-phase [N]` | Generate task plans for phase |
 | `/gsd:execute-plan` | Run single plan via subagent |
 | `/gsd:execute-phase <N>` | Execute all plans in phase N with parallel agents |
+| `/gsd:status [--wait]` | Check background agent status from parallel execution |
 | `/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 |

commands/gsd/help.md

@@ -130,6 +130,15 @@ Options (via `.planning/config.json` parallelization section):
 - `skip_checkpoints`: Skip human checkpoints in background (default: true)
 - `min_plans_for_parallel`: Minimum plans to trigger parallelization (default: 2)
 
+**`/gsd:status [--wait]`**
+Check status of background agents from parallel execution.
+
+- Shows running/completed agents from agent-history.json
+- Uses TaskOutput to poll agent status
+- With `--wait`: blocks until all agents complete
+
+Usage: `/gsd:status` or `/gsd:status --wait`
+
 ### Roadmap Management
 
 **`/gsd:add-phase <description>`**