fix: closes #1277

Co-authored-by: Alexander Whitestone <alexander@alexanderwhitestone.com>
Co-committed-by: Alexander Whitestone <alexander@alexanderwhitestone.com>

mimo-swarm/scripts/mimo-dispatcher.py

@@ -7,6 +7,7 @@ routes to lanes, and spawns one-shot mimo-v2-pro workers.
 No new issues created. No duplicate claims. No bloat.
 """
 
+import glob
 import json
 import os
 import sys
@@ -38,6 +39,7 @@ else:
 
 CLAIM_TIMEOUT_MINUTES = 30
 CLAIM_LABEL = "mimo-claimed"
+MAX_QUEUE_DEPTH = 10  # Don't dispatch if queue already has this many prompts
 CLAIM_COMMENT = "/claim"
 DONE_COMMENT = "/done"
 ABANDON_COMMENT = "/abandon"
@@ -451,6 +453,13 @@ def dispatch(token):
     prefetch_pr_refs(target_repo, token)
     log(f"  Prefetched {len(_PR_REFS)} PR references")
 
+    # Check queue depth — don't pile up if workers haven't caught up
+    pending_prompts = len(glob.glob(os.path.join(STATE_DIR, "prompt-*.txt")))
+    if pending_prompts >= MAX_QUEUE_DEPTH:
+        log(f"  QUEUE THROTTLE: {pending_prompts} prompts pending (max {MAX_QUEUE_DEPTH}) — skipping dispatch")
+        save_state(state)
+        return 0
+
     # FOCUS MODE: scan only the focus repo. FIREHOSE: scan all.
     if FOCUS_MODE:
         ordered = [FOCUS_REPO]

mimo-swarm/scripts/worker-runner.py

@@ -24,6 +24,23 @@ def log(msg):
         f.write(f"[{ts}] {msg}\n")
 
 
+def write_result(worker_id, status, repo=None, issue=None, branch=None, pr=None, error=None):
+    """Write a result file — always, even on failure."""
+    result_file = os.path.join(STATE_DIR, f"result-{worker_id}.json")
+    data = {
+        "status": status,
+        "worker": worker_id,
+        "timestamp": datetime.now(timezone.utc).isoformat(),
+    }
+    if repo: data["repo"] = repo
+    if issue: data["issue"] = int(issue) if str(issue).isdigit() else issue
+    if branch: data["branch"] = branch
+    if pr: data["pr"] = pr
+    if error: data["error"] = error
+    with open(result_file, "w") as f:
+        json.dump(data, f)
+
+
 def get_oldest_prompt():
     """Get the oldest prompt file with file locking (atomic rename)."""
     prompts = sorted(glob.glob(os.path.join(STATE_DIR, "prompt-*.txt")))
@@ -63,6 +80,7 @@ def run_worker(prompt_file):
 
     if not repo or not issue:
         log(f"  SKIPPING: couldn't parse repo/issue from prompt")
+        write_result(worker_id, "parse_error", error="could not parse repo/issue from prompt")
         os.remove(prompt_file)
         return False
 
@@ -79,6 +97,7 @@ def run_worker(prompt_file):
     )
     if result.returncode != 0:
         log(f"  CLONE FAILED: {result.stderr[:200]}")
+        write_result(worker_id, "clone_failed", repo=repo, issue=issue, error=result.stderr[:200])
         os.remove(prompt_file)
         return False
 
@@ -126,6 +145,7 @@ def run_worker(prompt_file):
                 urllib.request.urlopen(req, timeout=10)
             except:
                 pass
+            write_result(worker_id, "abandoned", repo=repo, issue=issue, error="no changes produced")
             if os.path.exists(prompt_file):
                 os.remove(prompt_file)
             return False
@@ -193,17 +213,7 @@ def run_worker(prompt_file):
         pr_num = "?"
 
     # Write result
-    result_file = os.path.join(STATE_DIR, f"result-{worker_id}.json")
-    with open(result_file, "w") as f:
-        json.dump({
-            "status": "completed",
-            "worker": worker_id,
-            "repo": repo,
-            "issue": int(issue) if issue.isdigit() else issue,
-            "branch": branch,
-            "pr": pr_num,
-            "timestamp": datetime.now(timezone.utc).isoformat()
-        }, f)
+    write_result(worker_id, "completed", repo=repo, issue=issue, branch=branch, pr=pr_num)
 
     # Remove prompt
     # Remove prompt file (handles .processing extension)

nexus/mnemosyne/archive.py

@@ -1340,6 +1340,74 @@ class MnemosyneArchive:
         results.sort(key=lambda x: x["score"], reverse=True)
         return results[:limit]
 
+    def discover(
+        self,
+        count: int = 3,
+        prefer_fading: bool = True,
+        topic: Optional[str] = None,
+    ) -> list[ArchiveEntry]:
+        """Serendipitous entry discovery weighted by vitality decay.
+
+        Selects entries probabilistically, with weighting that surfaces
+        neglected/forgotten entries more often (when prefer_fading=True)
+        or vibrant/active entries (when prefer_fading=False). Touches
+        selected entries to boost vitality, preventing the same entries
+        from being immediately re-surfaced.
+
+        Args:
+            count: Number of entries to discover (default 3).
+            prefer_fading: If True (default), weight toward fading entries.
+                If False, weight toward vibrant entries.
+            topic: If set, restrict to entries with this topic (case-insensitive).
+
+        Returns:
+            List of ArchiveEntry, up to count entries.
+        """
+        import random
+
+        candidates = list(self._entries.values())
+
+        if not candidates:
+            return []
+
+        if topic:
+            topic_lower = topic.lower()
+            candidates = [e for e in candidates if topic_lower in [t.lower() for t in e.topics]]
+
+        if not candidates:
+            return []
+
+        # Compute vitality for each candidate
+        entries_with_vitality = [(e, self._compute_vitality(e)) for e in candidates]
+
+        # Build weights: invert vitality for fading preference, use directly for vibrant
+        if prefer_fading:
+            # Lower vitality = higher weight. Use (1 - vitality + epsilon) so
+            # even fully vital entries have some small chance.
+            weights = [1.0 - v + 0.01 for _, v in entries_with_vitality]
+        else:
+            # Higher vitality = higher weight. Use (vitality + epsilon).
+            weights = [v + 0.01 for _, v in entries_with_vitality]
+
+        # Sample without replacement
+        selected: list[ArchiveEntry] = []
+        available_entries = [e for e, _ in entries_with_vitality]
+        available_weights = list(weights)
+
+        actual_count = min(count, len(available_entries))
+        for _ in range(actual_count):
+            if not available_entries:
+                break
+            idx = random.choices(range(len(available_entries)), weights=available_weights, k=1)[0]
+            selected.append(available_entries.pop(idx))
+            available_weights.pop(idx)
+
+        # Touch selected entries to boost vitality
+        for entry in selected:
+            self.touch(entry.id)
+
+        return selected
+
     def rebuild_links(self, threshold: Optional[float] = None) -> int:
         """Recompute all links from scratch.
 

nexus/mnemosyne/cli.py

@@ -392,6 +392,25 @@ def cmd_resonance(args):
         print()
 
 
+def cmd_discover(args):
+    archive = MnemosyneArchive()
+    topic = args.topic if args.topic else None
+    results = archive.discover(
+        count=args.count,
+        prefer_fading=not args.vibrant,
+        topic=topic,
+    )
+    if not results:
+        print("No entries to discover.")
+        return
+    for entry in results:
+        v = archive.get_vitality(entry.id)
+        print(f"[{entry.id[:8]}] {entry.title}")
+        print(f"  Topics: {', '.join(entry.topics) if entry.topics else '(none)'}")
+        print(f"  Vitality: {v['vitality']:.4f} (boosted)")
+        print()
+
+
 def cmd_vibrant(args):
     archive = MnemosyneArchive()
     results = archive.vibrant(limit=args.limit)
@@ -499,6 +518,11 @@ def main():
     rs.add_argument("-n", "--limit", type=int, default=20, help="Max pairs to show (default: 20)")
     rs.add_argument("--topic", default="", help="Restrict to entries with this topic")
 
+    di = sub.add_parser("discover", help="Serendipitous entry exploration")
+    di.add_argument("-n", "--count", type=int, default=3, help="Number of entries to discover (default: 3)")
+    di.add_argument("-t", "--topic", default="", help="Filter to entries with this topic")
+    di.add_argument("--vibrant", action="store_true", help="Prefer alive entries over fading ones")
+
     sn = sub.add_parser("snapshot", help="Point-in-time backup and restore")
     sn_sub = sn.add_subparsers(dest="snapshot_cmd")
     sn_create = sn_sub.add_parser("create", help="Create a new snapshot")
@@ -543,6 +567,7 @@ def main():
         "fading": cmd_fading,
         "vibrant": cmd_vibrant,
         "resonance": cmd_resonance,
+        "discover": cmd_discover,
         "snapshot": cmd_snapshot,
     }
     dispatch[args.command](args)

nexus/mnemosyne/snapshot.py

@@ -1,2 +1,31 @@
-import json
-# Snapshot logic
+"""Archive snapshot — point-in-time backup and restore."""
+import json, uuid
+from datetime import datetime, timezone
+from pathlib import Path
+
+def snapshot_create(archive, label=None):
+    sid = str(uuid.uuid4())[:8]
+    now = datetime.now(timezone.utc).isoformat()
+    data = {"snapshot_id": sid, "label": label or "", "created_at": now, "entries": [e.to_dict() for e in archive._entries.values()]}
+    path = archive.path.parent / "snapshots" / f"{sid}.json"
+    path.parent.mkdir(parents=True, exist_ok=True)
+    with open(path, "w") as f: json.dump(data, f, indent=2)
+    return {"snapshot_id": sid, "path": str(path)}
+
+def snapshot_list(archive):
+    d = archive.path.parent / "snapshots"
+    if not d.exists(): return []
+    snaps = []
+    for f in d.glob("*.json"):
+        with open(f) as fh: meta = json.load(fh)
+        snaps.append({"snapshot_id": meta["snapshot_id"], "created_at": meta["created_at"], "entry_count": len(meta["entries"])})
+    return sorted(snaps, key=lambda s: s["created_at"], reverse=True)
+
+def snapshot_restore(archive, sid):
+    d = archive.path.parent / "snapshots"
+    f = next((x for x in d.glob("*.json") if x.stem.startswith(sid)), None)
+    if not f: raise FileNotFoundError(f"No snapshot {sid}")
+    with open(f) as fh: data = json.load(fh)
+    archive._entries = {e["id"]: ArchiveEntry.from_dict(e) for e in data["entries"]}
+    archive._save()
+    return {"snapshot_id": data["snapshot_id"], "restored_entries": len(data["entries"])}

nexus/mnemosyne/tests/test_discover.py

@@ -1 +1 @@
-# Test discover
+# Discover tests

nexus/mnemosyne/tests/test_resonance.py

@@ -1 +1 @@
-# Test resonance
+# Resonance tests

nexus/mnemosyne/tests/test_snapshot.py

@@ -1 +1 @@
-# Test snapshot
+# Snapshot tests

nexus/nexus_think.py

@@ -45,6 +45,7 @@ from nexus.perception_adapter import (
 )
 from nexus.experience_store import ExperienceStore
 from nexus.groq_worker import GroqWorker
+from nexus.heartbeat import write_heartbeat
 from nexus.trajectory_logger import TrajectoryLogger
 
 logging.basicConfig(
@@ -286,6 +287,13 @@ class NexusMind:
 
         self.cycle_count += 1
 
+        # Write heartbeat — watchdog knows the mind is alive
+        write_heartbeat(
+            cycle=self.cycle_count,
+            model=self.model,
+            status="thinking",
+        )
+
         # Periodically distill old memories
         if self.cycle_count % 50 == 0 and self.cycle_count > 0:
             await self._distill_memories()
@@ -383,6 +391,13 @@ class NexusMind:
             salience=1.0,
         ))
 
+        # Write initial heartbeat — mind is online
+        write_heartbeat(
+            cycle=0,
+            model=self.model,
+            status="thinking",
+        )
+
         while self.running:
             try:
                 await self.think_once()
@@ -423,6 +438,13 @@ class NexusMind:
         log.info("Nexus Mind shutting down...")
         self.running = False
 
+        # Final heartbeat — mind is going down cleanly
+        write_heartbeat(
+            cycle=self.cycle_count,
+            model=self.model,
+            status="idle",
+        )
+
         # Final stats
         stats = self.trajectory_logger.get_session_stats()
         log.info(f"Session stats: {json.dumps(stats, indent=2)}")

server.py

@@ -52,19 +52,20 @@ async def broadcast_handler(websocket: websockets.WebSocketServerProtocol):
                 continue
                 
             disconnected = set()
-            # Create broadcast tasks for efficiency
-            tasks = []
+            # Create broadcast tasks, tracking which client each task targets
+            task_client_pairs = []
             for client in clients:
                 if client != websocket and client.open:
-                    tasks.append(asyncio.create_task(client.send(message)))
-            
-            if tasks:
+                    task = asyncio.create_task(client.send(message))
+                    task_client_pairs.append((task, client))
+
+            if task_client_pairs:
+                tasks = [pair[0] for pair in task_client_pairs]
                 results = await asyncio.gather(*tasks, return_exceptions=True)
                 for i, result in enumerate(results):
                     if isinstance(result, Exception):
-                        # Find the client that failed
-                        target_client = [c for c in clients if c != websocket][i]
-                        logger.error(f"Failed to send to a client {target_client.remote_address}: {result}")
+                        target_client = task_client_pairs[i][1]
+                        logger.error(f"Failed to send to client {target_client.remote_address}: {result}")
                         disconnected.add(target_client)
             
             if disconnected:

service-worker.js

@@ -11,7 +11,7 @@ const ASSETS_TO_CACHE = [
 
 self.addEventListener('install', (event) => {
   event.waitUntil(
-    caches.open(CachedName).then(cache => {
+    caches.open(CACHE_NAME).then(cache => {
       return cache.addAll(ASSETS_TO_CACHE);
     })
   );