nexus/mnemosyne/archive.py

@@ -510,6 +510,77 @@ class MnemosyneArchive:
         bridges.sort(key=lambda b: b["components_after_removal"], reverse=True)
         return bridges
 
+    def add_tags(self, entry_id: str, tags: list[str]) -> ArchiveEntry:
+        """Add new tags to an existing entry (deduplicates, case-preserving).
+
+        Args:
+            entry_id: ID of the entry to update.
+            tags: Tags to add. Already-present tags (case-insensitive) are skipped.
+
+        Returns:
+            The updated ArchiveEntry.
+
+        Raises:
+            KeyError: If entry_id does not exist.
+        """
+        entry = self._entries.get(entry_id)
+        if entry is None:
+            raise KeyError(entry_id)
+        existing_lower = {t.lower() for t in entry.topics}
+        for tag in tags:
+            if tag.lower() not in existing_lower:
+                entry.topics.append(tag)
+                existing_lower.add(tag.lower())
+        self._save()
+        return entry
+
+    def remove_tags(self, entry_id: str, tags: list[str]) -> ArchiveEntry:
+        """Remove specific tags from an existing entry (case-insensitive match).
+
+        Args:
+            entry_id: ID of the entry to update.
+            tags: Tags to remove. Tags not present are silently ignored.
+
+        Returns:
+            The updated ArchiveEntry.
+
+        Raises:
+            KeyError: If entry_id does not exist.
+        """
+        entry = self._entries.get(entry_id)
+        if entry is None:
+            raise KeyError(entry_id)
+        remove_lower = {t.lower() for t in tags}
+        entry.topics = [t for t in entry.topics if t.lower() not in remove_lower]
+        self._save()
+        return entry
+
+    def retag(self, entry_id: str, tags: list[str]) -> ArchiveEntry:
+        """Replace all tags on an existing entry (deduplicates new list).
+
+        Args:
+            entry_id: ID of the entry to update.
+            tags: New tag list. Duplicates (case-insensitive) are collapsed.
+
+        Returns:
+            The updated ArchiveEntry.
+
+        Raises:
+            KeyError: If entry_id does not exist.
+        """
+        entry = self._entries.get(entry_id)
+        if entry is None:
+            raise KeyError(entry_id)
+        seen: set[str] = set()
+        deduped: list[str] = []
+        for tag in tags:
+            if tag.lower() not in seen:
+                seen.add(tag.lower())
+                deduped.append(tag)
+        entry.topics = deduped
+        self._save()
+        return entry
+
     def rebuild_links(self, threshold: Optional[float] = None) -> int:
         """Recompute all links from scratch.
 

nexus/mnemosyne/cli.py

@@ -2,7 +2,8 @@
 
 Provides: mnemosyne ingest, mnemosyne search, mnemosyne link, mnemosyne stats,
           mnemosyne topics, mnemosyne remove, mnemosyne export,
-          mnemosyne clusters, mnemosyne hubs, mnemosyne bridges, mnemosyne rebuild
+          mnemosyne clusters, mnemosyne hubs, mnemosyne bridges, mnemosyne rebuild,
+          mnemosyne tag, mnemosyne untag, mnemosyne retag
 """
 
 from __future__ import annotations
@@ -143,6 +144,42 @@ def cmd_rebuild(args):
     print(f"Rebuilt links: {total} connections across {archive.count} entries")
 
 
+def cmd_tag(args):
+    archive = MnemosyneArchive()
+    tags = [t.strip() for t in args.tags.split(",") if t.strip()]
+    try:
+        entry = archive.add_tags(args.entry_id, tags)
+    except KeyError:
+        print(f"Entry not found: {args.entry_id}")
+        sys.exit(1)
+    print(f"[{entry.id[:8]}] {entry.title}")
+    print(f"  Topics: {', '.join(entry.topics) if entry.topics else '(none)'}")
+
+
+def cmd_untag(args):
+    archive = MnemosyneArchive()
+    tags = [t.strip() for t in args.tags.split(",") if t.strip()]
+    try:
+        entry = archive.remove_tags(args.entry_id, tags)
+    except KeyError:
+        print(f"Entry not found: {args.entry_id}")
+        sys.exit(1)
+    print(f"[{entry.id[:8]}] {entry.title}")
+    print(f"  Topics: {', '.join(entry.topics) if entry.topics else '(none)'}")
+
+
+def cmd_retag(args):
+    archive = MnemosyneArchive()
+    tags = [t.strip() for t in args.tags.split(",") if t.strip()]
+    try:
+        entry = archive.retag(args.entry_id, tags)
+    except KeyError:
+        print(f"Entry not found: {args.entry_id}")
+        sys.exit(1)
+    print(f"[{entry.id[:8]}] {entry.title}")
+    print(f"  Topics: {', '.join(entry.topics) if entry.topics else '(none)'}")
+
+
 def main():
     parser = argparse.ArgumentParser(prog="mnemosyne", description="The Living Holographic Archive")
     sub = parser.add_subparsers(dest="command")
@@ -184,6 +221,18 @@ def main():
     rb = sub.add_parser("rebuild", help="Recompute all links from scratch")
     rb.add_argument("-t", "--threshold", type=float, default=None, help="Similarity threshold override")
 
+    tg = sub.add_parser("tag", help="Add tags to an existing entry")
+    tg.add_argument("entry_id", help="Entry ID")
+    tg.add_argument("tags", help="Comma-separated tags to add")
+
+    ut = sub.add_parser("untag", help="Remove tags from an existing entry")
+    ut.add_argument("entry_id", help="Entry ID")
+    ut.add_argument("tags", help="Comma-separated tags to remove")
+
+    rt = sub.add_parser("retag", help="Replace all tags on an existing entry")
+    rt.add_argument("entry_id", help="Entry ID")
+    rt.add_argument("tags", help="Comma-separated new tag list")
+
     args = parser.parse_args()
     if not args.command:
         parser.print_help()
@@ -201,6 +250,9 @@ def main():
         "hubs": cmd_hubs,
         "bridges": cmd_bridges,
         "rebuild": cmd_rebuild,
+        "tag": cmd_tag,
+        "untag": cmd_untag,
+        "retag": cmd_retag,
     }
     dispatch[args.command](args)
 

nexus/mnemosyne/tests/test_archive.py

@@ -343,3 +343,151 @@ def test_archive_topic_counts():
         assert counts["automation"] == 2
         # sorted by count desc — both tied but must be present
         assert set(counts.keys()) == {"python", "automation"}
+
+
+# --- Tag management tests ---
+
+def test_add_tags_basic():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        e = ingest_event(archive, title="T", content="c", topics=["alpha"])
+        archive.add_tags(e.id, ["beta", "gamma"])
+        fresh = archive.get(e.id)
+        assert "beta" in fresh.topics
+        assert "gamma" in fresh.topics
+        assert "alpha" in fresh.topics
+
+
+def test_add_tags_deduplication():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        e = ingest_event(archive, title="T", content="c", topics=["alpha"])
+        archive.add_tags(e.id, ["alpha", "ALPHA", "beta"])
+        fresh = archive.get(e.id)
+        lower_topics = [t.lower() for t in fresh.topics]
+        assert lower_topics.count("alpha") == 1
+        assert "beta" in lower_topics
+
+
+def test_add_tags_missing_entry():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        try:
+            archive.add_tags("nonexistent-id", ["tag"])
+            assert False, "Expected KeyError"
+        except KeyError:
+            pass
+
+
+def test_add_tags_empty_list():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        e = ingest_event(archive, title="T", content="c", topics=["alpha"])
+        archive.add_tags(e.id, [])
+        fresh = archive.get(e.id)
+        assert fresh.topics == ["alpha"]
+
+
+def test_remove_tags_basic():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        e = ingest_event(archive, title="T", content="c", topics=["alpha", "beta", "gamma"])
+        archive.remove_tags(e.id, ["beta"])
+        fresh = archive.get(e.id)
+        assert "beta" not in fresh.topics
+        assert "alpha" in fresh.topics
+        assert "gamma" in fresh.topics
+
+
+def test_remove_tags_case_insensitive():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        e = ingest_event(archive, title="T", content="c", topics=["Python", "rust"])
+        archive.remove_tags(e.id, ["PYTHON"])
+        fresh = archive.get(e.id)
+        assert "Python" not in fresh.topics
+        assert "rust" in fresh.topics
+
+
+def test_remove_tags_missing_tag_silent():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        e = ingest_event(archive, title="T", content="c", topics=["alpha"])
+        archive.remove_tags(e.id, ["nope"])  # should not raise
+        fresh = archive.get(e.id)
+        assert fresh.topics == ["alpha"]
+
+
+def test_remove_tags_missing_entry():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        try:
+            archive.remove_tags("nonexistent-id", ["tag"])
+            assert False, "Expected KeyError"
+        except KeyError:
+            pass
+
+
+def test_retag_basic():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        e = ingest_event(archive, title="T", content="c", topics=["old1", "old2"])
+        archive.retag(e.id, ["new1", "new2"])
+        fresh = archive.get(e.id)
+        assert fresh.topics == ["new1", "new2"]
+
+
+def test_retag_deduplication():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        e = ingest_event(archive, title="T", content="c", topics=["x"])
+        archive.retag(e.id, ["go", "GO", "rust"])
+        fresh = archive.get(e.id)
+        lower_topics = [t.lower() for t in fresh.topics]
+        assert lower_topics.count("go") == 1
+        assert "rust" in lower_topics
+
+
+def test_retag_empty_list():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        e = ingest_event(archive, title="T", content="c", topics=["alpha"])
+        archive.retag(e.id, [])
+        fresh = archive.get(e.id)
+        assert fresh.topics == []
+
+
+def test_retag_missing_entry():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        archive = MnemosyneArchive(archive_path=path)
+        try:
+            archive.retag("nonexistent-id", ["tag"])
+            assert False, "Expected KeyError"
+        except KeyError:
+            pass
+
+
+def test_tag_persistence_across_reload():
+    with tempfile.TemporaryDirectory() as tmp:
+        path = Path(tmp) / "test_archive.json"
+        a1 = MnemosyneArchive(archive_path=path)
+        e = ingest_event(a1, title="T", content="c", topics=["alpha"])
+        a1.add_tags(e.id, ["beta"])
+        a1.remove_tags(e.id, ["alpha"])
+
+        a2 = MnemosyneArchive(archive_path=path)
+        fresh = a2.get(e.id)
+        assert "beta" in fresh.topics
+        assert "alpha" not in fresh.topics