Initial Arka plugin registry: Official plugins mirror + Arka-signed index

11 plugins from github.com/librefang/librefang-registry plugins/.
index.json / index.json.sig are signed with Arka's Ed25519 key
(not upstream stats.librefang.ai). Private key is not in this repo.

plugins/episodic-memory/hooks/ingest.py

@@ -0,0 +1,144 @@
+#!/usr/bin/env python3
+"""Episodic memory ingest hook.
+
+Loads the episode store for the current agent, scores completed episodes
+against the incoming message's keywords using keyword overlap ratio, and
+returns the top 2 matching episodes as contextual memories.
+
+This hook is read-only -- it never modifies the episode store.
+
+Receives via stdin:
+    {"type": "ingest", "agent_id": "...", "message": "user message text"}
+
+Prints to stdout:
+    {"type": "ingest_result", "memories": [{"content": "..."}]}
+"""
+import json
+import os
+import re
+import sys
+
+# ---------------------------------------------------------------------------
+# Stopwords & keyword extraction
+# ---------------------------------------------------------------------------
+
+STOPWORDS = frozenset({
+    "a", "an", "the", "and", "or", "but", "in", "on", "at", "to", "for",
+    "of", "with", "by", "from", "is", "are", "was", "were", "be", "been",
+    "being", "have", "has", "had", "do", "does", "did", "will", "would",
+    "could", "should", "may", "might", "shall", "can", "need", "must",
+    "it", "its", "i", "me", "my", "you", "your", "he", "she", "we",
+    "they", "them", "their", "this", "that", "these", "those", "what",
+    "which", "who", "how", "when", "where", "why", "if", "then", "so",
+    "not", "no", "just", "also", "very", "too", "about", "up", "out",
+    "all", "some", "any", "each", "every", "into", "over", "after",
+})
+
+MIN_WORD_LEN = 3
+
+# Minimum overlap ratio to consider an episode relevant
+MIN_OVERLAP = 0.2
+
+# Maximum episodes to return
+MAX_RESULTS = 2
+
+
+def extract_keywords(text):
+    """Extract deduplicated keywords from text.
+
+    Lowercases, removes stopwords, filters words shorter than MIN_WORD_LEN.
+    """
+    words = re.findall(r"[a-zA-Z][a-zA-Z0-9\-]*[a-zA-Z0-9]|[a-zA-Z]", text)
+    seen = set()
+    keywords = []
+    for w in words:
+        lower = w.lower()
+        if lower not in STOPWORDS and len(lower) >= MIN_WORD_LEN and lower not in seen:
+            seen.add(lower)
+            keywords.append(lower)
+    return keywords
+
+
+def load_episode_store(agent_id):
+    """Load the episode store JSON for the given agent. Returns None on failure."""
+    store_dir = os.path.join(
+        os.path.expanduser("~"), ".librefang", "plugins", "episodic-memory"
+    )
+    store_path = os.path.join(store_dir, f"{agent_id}.json")
+    if not os.path.isfile(store_path):
+        return None
+    try:
+        with open(store_path, "r", encoding="utf-8") as f:
+            return json.load(f)
+    except (json.JSONDecodeError, OSError):
+        return None
+
+
+def score_episode(episode_keywords, query_keywords):
+    """Compute keyword overlap ratio between an episode and the query.
+
+    overlap_ratio = |intersection| / |union|  (Jaccard similarity)
+    """
+    if not episode_keywords or not query_keywords:
+        return 0.0
+    ep_set = set(episode_keywords)
+    q_set = set(query_keywords)
+    intersection = ep_set & q_set
+    union = ep_set | q_set
+    if not union:
+        return 0.0
+    return len(intersection) / len(union)
+
+
+def main():
+    try:
+        request = json.loads(sys.stdin.read())
+    except (json.JSONDecodeError, ValueError):
+        print(json.dumps({"type": "ingest_result", "memories": []}))
+        return
+
+    message = request.get("message", "")
+    agent_id = request.get("agent_id", "")
+
+    if not message.strip() or not agent_id:
+        print(json.dumps({"type": "ingest_result", "memories": []}))
+        return
+
+    query_keywords = extract_keywords(message)
+    if not query_keywords:
+        print(json.dumps({"type": "ingest_result", "memories": []}))
+        return
+
+    store = load_episode_store(agent_id)
+    if not store:
+        print(json.dumps({"type": "ingest_result", "memories": []}))
+        return
+
+    episodes = store.get("episodes", [])
+
+    # Score only completed episodes
+    scored = []
+    for ep in episodes:
+        if ep.get("status") != "completed":
+            continue
+        overlap = score_episode(ep.get("keywords", []), query_keywords)
+        if overlap > MIN_OVERLAP:
+            scored.append((overlap, ep))
+
+    # Sort by overlap descending, take top MAX_RESULTS
+    scored.sort(key=lambda x: x[0], reverse=True)
+    top = scored[:MAX_RESULTS]
+
+    memories = []
+    for _score, ep in top:
+        timestamp = ep.get("ended", ep.get("started", "unknown"))
+        summary = ep.get("summary", "no summary")
+        memories.append({
+            "content": f"[episodic-memory] Past episode ({timestamp}): {summary}"
+        })
+
+    print(json.dumps({"type": "ingest_result", "memories": memories}))
+
+
+if __name__ == "__main__":
+    main()