Summary

Mnemosyne is currently excluded from the 8 bundled memory providers documented at /docs/user-guide/features/memory-providers.md and the provider comparison table, despite being the most feature-rich local-first option available and having an active Hermes plugin since v2.6.0.

Technical Comparison

Full Integration Audit

Core lifecycle - all implemented:

• register(), initialize(), is_available()
• system_prompt_block() - injects memory context instructions
• prefetch() + queue_prefetch() - background recall per turn
• sync_turn() - persists each completed turn
• get_tool_schemas() - exposes 19 tools
• handle_tool_call() - routes all 19 tool dispatches
• shutdown() - clean flush on exit

Setup wizard integration:

• get_config_schema() - 14 configurable fields for hermes memory setup
• save_config() - writes to $HERMES_HOME/plugins/mnemosyne/config.json

Optional hooks implemented:

• on_turn_start() - turn-level metrics tracking
• on_session_end() - triggers memory consolidation
• on_memory_write() - mirrors builtin memory writes to Mnemosyne backend

Three hooks not yet implemented (cosmetic gap, not blocking):

• on_session_switch() - /resume /branch session rotation
• on_pre_compress() - pre-compression insight extraction
• on_delegation() - subagent task observation

19 Tools Exposed

mnemosyne_remember, mnemosyne_recall, mnemosyne_stats, mnemosyne_triple_add, mnemosyne_triple_query, mnemosyne_sleep, mnemosyne_scratchpad_write, mnemosyne_scratchpad_read, mnemosyne_scratchpad_clear, mnemosyne_invalidate, mnemosyne_export, mnemosyne_import, mnemosyne_update, mnemosyne_forget, mnemosyne_diagnose, mnemosyne_graph_query, mnemosyne_graph_link, mnemosyne_get, mnemosyne_validate

This is the largest tool surface of any bundled provider (Honcho: 5 tools, Holographic: 2 tools, Supermemory: 4 tools).

Unique Capabilities Missing From All 8 Bundled Providers

1. Hybrid semantic + FTS5 + temporal ranking - combines vector similarity, full-text search, and recency/time-aware scoring
2. Multi-agent conflict detection - detects and resolves contradictory facts across sessions
3. Episodic consolidation - automatically compresses short-term working memories into long-term episodic summaries
4. Temporal knowledge graph - triple-based facts with validity windows (valid_from dates)
5. Strict fact matching - configurable fact recall precision (lenient vs strict) with entity prefix guards
6. Collaborative validation - cross-agent memory attestation via mnemosyne_validate
7. Graph traversal - multi-hop BFS through linked memories via mnemosyne_graph_query / graph_link
8. Memory export/import - full JSON backup and cross-instance migration

What Would Be Required for Inclusion

Minimal - no code changes to Hermes core:

1. Add Mnemosyne to the provider comparison table in /docs/user-guide/features/memory-providers.md
2. Add a Mnemosyne section with setup instructions (pip install + plugin symlink + config)
3. Register mnemosyne as a valid provider name in hermes memory setup if not already discoverable via $HERMES_HOME/plugins/

The Hermes plugin discovery system already supports user-installed providers in $HERMES_HOME/plugins/ - Mnemosyne would not need special treatment beyond documentation.

Why Now

• Mnemosyne hit v3.1.2 with strict fact matching, multi-agent validation, and conflict detection
• Multiple Hermes users are already deploying it (Docker, fly.io, PEP 668 systems) - community questions in help-desk show active adoption
• It fills a gap: of the 8 bundled providers, only 2 are truly local-first (Holographic and ByteRover). Mnemosyne adds vector search, FTS5 hybrid ranking, temporal scoring, and knowledge graphs - capabilities neither local option provides.
• Zero cloud dependency, no API key, no subscription, no usage limits