Engraphis is a local-first, open AI memory engine for agents — Ebbinghaus decay,
interaction-aware reinforcement, bi-temporal facts, hybrid recall, and a native
workspace → repo → session → memory hierarchy. Python 3.9+ for the core (Python 3.10+
for the server/MCP stack), FastAPI, SQLite, and local embeddings; the external LLM is optional
and pluggable.
This is the canonical operating manual for any AI agent working in this repo. CLAUDE.md
imports it. Read §0 before editing anything.
There are two parallel codebases under engraphis/. Confusing them is the single
most common mistake here.
| v2 — current architecture (build here) | v1 — legacy reference server | |
|---|---|---|
| Status | Primary scoped, bi-temporal, interface-driven implementation. | Compatibility/reference implementation with flat namespaces. |
| Model | Scoped + bi-temporal + typed; interface-driven. | Single flat namespace string per memory. |
| Code | engraphis/core/, engraphis/backends/, eval/, tests/, scripts/migrate_to_v2.py |
engraphis/app.py, config.py, models.py, routes/, stores/, engines/, llm/, static/ |
| Data | new v2 schema (SCHEMA_VERSION = 16) |
engraphis_v1.db |
| Entry | engraphis.MemoryEngine.create() / engraphis.create_memory_engine() → engraphis/factory.py → core/engine.py |
Internal reference only; never a public launcher |
Rule: build new capability on v2 (core/ + backends/) behind the interfaces.
Only touch the v1 server for compatibility fixes or to keep the reference running. When a
task is ambiguous, decide which side it belongs to before editing.
# ── Install ──────────────────────────────────────────────────────────────────
pip install numpy pytest # v2 core + tests, fully offline (Python 3.9 floor job)
pip install -e ".[test]" # full offline CI test/lint/typecheck dependencies
pip install -e ".[all,dev]" # complete local stack: dashboard, MCP, embeddings, dev tools
# Config: process environment or owner-private ~/.engraphis/config.env; never a searched CWD .env
# ── Primary offline gate (no API key — KEEP THIS GREEN; mirrors CI's full-stack job) ──
ruff check . # pinned lint rules
python scripts/check_commercial_manifest.py # source/service boundary
python scripts/externalize_dashboard_assets.py # strict-CSP asset drift
python -m pytest tests/ -q # full offline unit suite
python -m eval.harness --dataset eval/datasets/sample.jsonl --k 5 # retrieval eval gate
python -m eval.harness --dataset eval/datasets/codemem.jsonl --k 5 # coding/conflict gate
python -m eval.ablation # vector-only vs hybrid
python -m eval.reinforcement # bounded retention trajectory
python -m eval.adversarial_memory_security # prompt/graph boundary
pyright # core + backends typecheck
# ── External benchmarks (real numbers need torch + the dataset; see eval/external.py) ──
python -m eval.external --dataset locomo10.json --format locomo --k 10 # LoCoMo
python -m eval.external --dataset longmemeval_s.json --format longmemeval # LongMemEval
python -m eval.external --dataset locomo10.json --format locomo --offline --limit 2 # plumbing check
# ── Unified dashboard + memory inspector ──
python -m scripts.start_dashboard # http://127.0.0.1:8700
# Use this unified launcher; there is no separate Inspector service.
# ── Onboarding (writes owner-private ~/.engraphis/config.env; doctor verifies install) ──
engraphis-init # or: python -m scripts.init
engraphis-init --check
# ── Customer-side hosted session ───────────────────────────────────────────
ENGRAPHIS_CLOUD_CONTROL_URL=https://api.engraphis.com
ENGRAPHIS_CLOUD_REFRESH_CREDENTIAL=... # secret; prefer the owner-only session file
ENGRAPHIS_CLOUD_TOKEN_SUBJECT=member # device or member, fixed at bootstrap
# Authorization, billing, relay, compute, and worker implementations are private services.
# ── Sleep-time consolidation (schedulable local job; also an MCP tool) ────────
python -m scripts.consolidate --db engraphis.db --workspace acme --dry-run
# ── Sync (local shared-folder transport or hosted Cloud Sync — see docs/SYNC.md) ──
python -m scripts.sync --db engraphis.db --workspace acme --remote ~/Dropbox/engraphis --dry-run
python -m scripts.sync --db engraphis.db --workspace acme --relay https://relay.engraphis.com # or bare --relay + ENGRAPHIS_RELAY_URL
# ── Compatibility server alias (v2, headless; needs the full install) ────────
python -m scripts.start_server # same v2 app as engraphis-dashboard, without opening a browser
python -m scripts.cli recall "what do we know about X" -n vault # CLI: ingest/recall/chat/thoughts/list
# ── v2 data migration (v1 flat namespaces → v2 scoped/bi-temporal) ───────────
python -m scripts.migrate_to_v2 --old engraphis_v1.db --new engraphis_v2.db --dry-run
python -m scripts.migrate_to_v2 --old engraphis_v1.db --new engraphis_v2.db
requires-python >= 3.9 (ruff targets py39). CI tests the NumPy-only core on 3.9, the full
offline stack on 3.10–3.14, and Pyright on 3.11; dedicated jobs also exercise encryption and built
artifacts. .github/workflows/ci.yml is authoritative when the matrix changes.
core/recall.py::RecallEngine.recall() is the heart of the system. Flow:
query
└─ SearchFilter (scope + valid_at/known_at anchors) core/interfaces.py
└─ optional QueryPlanner (off by default; original + at most 2 routes)
core/query_planner.py
└─ 4 retrieval arms (executed deterministically, then fused):
• vector — VectorIndex.search (cosine) backends/vector_*.py
• lexical — Store.fts_search (FTS5/BM25 + LIKE fallback) core/store.py
• graph — Personalized PageRank over entities+links core/recall.py + core/graphrank.py
(graph_mode="1hop" keeps the old expansion for ablation)
• code — symbols/files/calls with memory bridges core/engine.py
└─ priority-weighted query/arm RRF + six-term score core/scoring.py
└─ rerank top-N backends/reranker.py
└─ optional post-rerank memory-type maxima
└─ context packing (token budget) + optional explicit reinforcement
core/recall.py / core/store.py
Backends are selected by get_embedder() / get_vector_index() / get_reranker() and
injected through MemoryEngine — never imported directly inside core/ (see §3.1).
Grounded recall (MemoryEngine.grounded_recall() → core/grounded.py) wraps recall():
it answers strictly from the retrieved memories with [n] citations, or abstains when the
absolute query↔memory support (max of semantic cosine and lexical Jaccard, recomputed here — the
recall score is per-query-normalised and can't gate a fixed threshold) is below
GROUNDED_SUPPORT_FLOOR. Offline and deterministic (extractive answer) by default; an optional
LLM (injected, never imported in core/) can synthesise prose under the same source/abstain
contract, degrading to the extractive answer on any error. The abstain gate is what makes
"grounded, not guessed" real — an off-topic query doesn't get the nearest-neighbour dressed up as
fact. Measured by eval/grounded.py (answerable→ground, off-topic→abstain).
The write path (MemoryEngine.remember_with_resolution()) mirrors this: embed → find
same-scope neighbors via the vector index → core/resolve.py::resolve() decides
ADD / NOOP (reinforce, don't duplicate) / INVALIDATE (close old validity, insert new) from
two deterministic signals — token-overlap on the text itself, plus the embedding cosine
already computed at write time as joint evidence for strongly overlapping unkeyed text — no LLM
call on untrusted input. The dependency-free hashing embedder is lexical, so genuinely reworded
mutable facts need a stable subject_key/claim_kind (or explicit correction), not a cosine
threshold. An INVALIDATE also records
metadata.supersedes on the new record so the chain is queryable (why/timeline/Inspector).
After the decision, memory evolution (MemoryEngine._evolve, A-MEM-style) auto-links the
new memory to its closest live neighbors (bounded, idempotent, audited) and gives them a small
reinforcement touch. remember() is a thin wrapper that returns just the resulting id; use
remember_with_resolution() when you need the decision detail. MemoryEngine.ingest() is the
extract-then-remember path: with an Extractor configured (ENGRAPHIS_EXTRACTOR=llm) raw text
is distilled into discrete facts first; the offline default is passthrough.
- Interfaces before implementations. Every module in
core/, includingcore/engine.py, depends only on the Protocols incore/interfaces.py(Embedder,VectorIndex,LexicalIndex,GraphStore,Reranker,LLM) and injected collaborators. The sole outer composition root isengraphis/factory.py, which may import concrete backends and selects the dependency-lightIdentityRerankerdefault.engraphis/__init__.pyregisters that provider so the compatibilityMemoryEngine.create()entry point delegates outward; new callers may useengraphis.create_memory_engine()directly. Never import a concrete backend anywhere insidecore/. Swappingsqlite-vec→Qdrant, or a local embedder for an API, must be a config change, not a refactor. - Forgetting lowers retrieval priority; it never hard-deletes. Decay adjusts
stability. Hard deletion is explicit, governed, and audited (Store.audit). - Truth is temporal. Resolve contradictions by invalidation, not overwrite:
Store.close_validity()/invalidate_edge()setvalid_to. Preserve history; supportas_oftime-travel reads. - Everything is scoped. Every memory carries a
Scope+workspace/repo/session. Every read takes aSearchFilter. Scope promotion is an explicit operation. - Memory is typed (
working/episodic/semantic/procedural), each with its own weight profile (scoring.DEFAULT_WEIGHTS) and lifecycle. The append-only event ledger is outside that type system: userecord_eventfor raw occurrences and an episodic memory when the outcome must be recalled or consolidated. - Provenance always. Set
provenanceon memories and edges so "why is this known?" is answerable. - Prove "better" with a number. No retrieval/quality claim ships without an eval.
Keep the CI gate green; extend
eval/when you change ranking. - Local-first & offline-capable. The core must run with only
numpy(deterministic embedder + NumPy index). Do not add hard dependencies tocore/; gate heavy imports (sentence-transformers, sqlite-vec) behind the backend factories.
- Ordinary recall score (
score_memory):score = w_r·retention + w_s·semantic + w_l·lexical + w_g·graph + w_i·importance − w_x·staleness. Arm scores are min-max normalized before fusion so no arm dominates by raw scale. Recency (c) is used only by the separate queryless proactive agenda, avoiding a second age penalty alongside retention in ordinary recall. Default weights:r1.0 s1.0 l0.5 g0.7 i0.6 c0.3 x0.8, overridden per memory type. - Ebbinghaus retention:
R(t) = exp(−Δt_days / S). - Reinforcement (spacing effect): each event adds
(α·min(S, 1) + boost)·ln(1 + 1/access_count),α = 0.3, with a 100-day cap. The cumulative trajectory is logarithmic and bounded; this isStore.reinforce(). - Interaction boosts (
scoring.INTERACTION_BOOST): view/read 0.05 · recall 0.15 · react 0.20 · engage 0.30 · reply 0.50 · create 1.00. - Reciprocal Rank Fusion:
1 / (k + rank + 1),k = 60.
These are pure, unit-tested functions — change them only with a corresponding tests/ +
eval/ update.
- Scope hierarchy:
workspace → repo → session → memory. Scopes:session|repo|workspace|user. - Bi-temporal validity on every record: world-time
valid_from/valid_to+ system-timeingested_at/expired_at. Reads hide facts outside their validity window unlessinclude_invalid=Trueor anas_ofanchor is given. - IDs: ULID, time-sortable, typed prefixes (
ws_,repo_,ses_,mem_,ent_,edg_,sym_,evt_,job_,aud_,dev_,rcpt_,vlt_,src_) —core/ids.py. Lexicographic sort == chronological. - Tables:
workspaces,repos,sessions,memories,mem_vectors,embedding_state,mem_fts(FTS5 + plain-table fallback),entities,edges(bi-temporal),mem_links,memory_entities,symbols,code_edges,code_files,code_memory_links,operation_receipts,events,audit,memory_tombstones,source_vaults,source_imports,source_import_items,schema_migrations. - Local document sources: source collections are scope-bound, resumable manifests. Their
paths, digests, and import state are provenance; source folders never create implicit memory
scopes.
kind="documents"is the source-neutral adapter, whilekind="obsidian"retains the rich Markdown adapter and its existing lineage. Import jobs persist the optional session target, and schema checks keep source-job lineage and per-job items in that exact session. - Erasure markers contain no memory content.
memory_tombstones.export_classis strictlynever_export|remote_erasure; onlyremote_erasuremay cross a sync boundary. - Vectors are stored L2-normalized so cosine similarity == dot product.
- Offline by default at the public factory:
engraphis.MemoryEngine.create()andengraphis.create_memory_engine()select a deterministic hashing embedder + NumPy index, so tests need no model download or network. Passembed_model=...to load a real embedding model; choosevector_backend="sqlite-vec"separately when you need native exact-KNN acceleration. - First full-stack run downloads
all-MiniLM-L6-v2(~80 MB) for the ST embedder. - FTS5 may be missing on some SQLite builds →
Storeauto-falls back toLIKE(self.has_fts5). Don't assume BM25 is available. - Secrets & data are git-ignored:
.env,engraphis_v1.db,*.db-wal,*.db-shm. Never commit, print, or paste their contents. - Git history is authoritative: use
git log/git blamefor implementation history andCHANGELOG.mdfor release-level summaries. Keep commits logical and descriptive. - Synced-folder flakiness: if the repo sits on OneDrive (or any host-to-sandbox mount), a
transient
SyntaxError,AttributeErrorfor a method you just added, or a shell command reading back fewer lines than you just wrote is mid-sync, not your code. A single re-run is sometimes not enough — if a file's content looks stale from the shell after an edit, the reliable fix is to rewrite that file's content directly from the shell (e.g. a heredoc) and re-verify withwc -l/grepbefore trusting a test run against it; clearing__pycache__alone does not fix this (the staleness is in the source, not in cached bytecode).
README.md— installation, product surfaces, configuration, and public API usage.CHANGELOG.md— shipped capability and release history. Keep phase/status ledgers out of this operating manual.docs/HOSTED_PLANS.md— concise pricing, plan contents, trial, and hosted-service boundary.docs/MCP_TOOLS.md— standalone inventory of the public MCP surface; keep it synchronized withengraphis/mcp_server.py.docs/SYNC.md— cloud sync (Pro): architecture, the convergent merge, CLI usage, and the untrusted-bundle security model.docs/DOCUMENT_IMPORT.md— universal local-document import, source safety, re-import, conflicts, format adapters, and dashboard/CLI flows. Keep it synchronized with the parser, importer, dashboard, and import-report schema.docs/OBSIDIAN_IMPORT.md— the rich Obsidian Markdown adapter (frontmatter, wikilinks, aliases, attachments) and its compatibility command. It supplements, rather than replaces, the universal document-import guide.AGENTS.md(this file) +CLAUDE.md— how to work in the repo.skills/engraphis-memory/— portable Agent Skill (SKILL.md +references/) that teaches any MCP-capable agent the memory discipline (when to remember/recall, scoping, tool selection). Shipped as a Claude Code plugin via.claude-plugin/(marketplace.json+plugin.json). It documents the tool surface inengraphis/mcp_server.py, so keep tool names/params in sync when you change that file — this is a docs-drift surface likeREADME.md.
When code and docs disagree, the code wins — then fix the doc in the same change.