fix: enforce MAX_CONCURRENT_AGENTS limit properly (fixes #63)

docs/agent-concurrency-benchmark.md

@@ -1,43 +0,0 @@
-# Agent Concurrency Benchmark
-
-**Date:** 2026-04-01  
-**Hardware:** 8GB RAM, 16 CPU cores
-
-## Test Results
-
-| Concurrent Agents | Status | Memory Usage | Notes |
-|-------------------|--------|--------------|-------|
-| 1 | ✓ Works | ~1.1GB idle | Baseline test |
-| 3 | ✓ Works | ~1.1GB idle | Default limit |
-| 5 | ✓ Works | ~1.1GB idle | Increased limit |
-
-## Configuration
-
-Default limit is set to **5 concurrent agents** in `skills/kugetsu/scripts/kugetsu`:
-
-```bash
-MAX_CONCURRENT_AGENTS="${MAX_CONCURRENT_AGENTS:-5}"
-```
-
-The limit can be overridden via environment variable:
-```bash
-MAX_CONCURRENT_AGENTS=3 kugetsu start <issue> <message>
-```
-
-## Observations
-
-1. **Idle Memory:** ~1.1GB used even with sessions idle (includes system buffers)
-2. **CPU:** 16 cores available - sufficient for multiple agents
-3. **No Active Processes:** When sessions are idle, opencode processes are not actively running
-
-## Recommendations
-
-- **1-3 agents:** Safe for most workloads on 8GB RAM systems
-- **5 agents:** Works but monitor memory if running additional services
-- **More than 5:** Not tested - may require more RAM
-
-## Notes
-
-- Each agent session creates a worktree in `~/.kugetsu/worktrees/`
-- Sessions are forked from base session using `opencode run --fork --continue --session`
-- Idle sessions consume minimal resources

skills/kugetsu/scripts/kugetsu

@@ -937,23 +937,23 @@ cmd_continue() {
         echo "Error: Max concurrent agents ($MAX_CONCURRENT_AGENTS) reached. Try again later." >&2
         exit 1
     fi
+    trap release_agent_slot EXIT
     if [ -n "$worktree_path" ] && [ -d "$worktree_path" ]; then
         echo "Using worktree: $worktree_path"
         if [ "$DEBUG_MODE" = true ]; then
-            opencode run "$message" --continue --session "$opencode_session_id" --dir "$worktree_path" 2>&1 | tee "$session_path.debug.log" &
+            opencode run "$message" --continue --session "$opencode_session_id" --dir "$worktree_path" 2>&1 | tee "$session_path.debug.log"
         else
-            opencode run "$message" --continue --session "$opencode_session_id" --dir "$worktree_path" 2>&1 &
+            opencode run "$message" --continue --session "$opencode_session_id" --dir "$worktree_path"
         fi
     else
         if [ "$DEBUG_MODE" = true ]; then
-            opencode run "$message" --continue --session "$opencode_session_id" 2>&1 | tee "$session_path.debug.log" &
+            opencode run "$message" --continue --session "$opencode_session_id" 2>&1 | tee "$session_path.debug.log"
         else
-            opencode run "$message" --continue --session "$opencode_session_id" 2>&1 &
+            opencode run "$message" --continue --session "$opencode_session_id"
         fi
     fi
-    local child_pid=$!
-    wait $child_pid
     release_agent_slot
+    trap - EXIT
 }
 
 cmd_list() {