ReasonGraph

A graph-based memory for AI agents: it ingests facts, auto-extracts entities and cause->effect relations, and discovers connections across independent documents and across agent sessions -- with conflict resolution, time-travel, causal tracing, and counterfactuals.

Why ReasonGraph?

Standard RAG retrieves documents similar to your query. ReasonGraph is a persistent, updatable memory that discovers connections between facts that were written independently.

When you feed text into add_texts(), ReasonGraph automatically extracts entities (via GLiNER) and cause-effect relations (via a dedicated causal model) that become nodes and typed edges in a graph. Facts that share entities or causal chains get connected -- even if they never reference each other. Multi-hop traversal then walks these connections to build reasoning chains that span multiple sources.

On top of retrieval it works as agent memory: scopes/sessions (agents discover into each other's memory through shared entities), contradiction resolution (a new fact soft-supersedes what it contradicts), time-travel (query(as_of=...)), causal tracing (trace_effects / root_causes / causal_chain), counterfactuals (what_if), and a shippable MemoryService over HTTP and MCP.

Zero config, strong defaults. ReasonGraph() picks the best available entity extractor, causal model, embedder, and reranker automatically -- the eval numbers below come from these defaults. For the SOTA causal model (~0.70 F1) use pip install reasongraph[causal] and the graph uses it automatically. The configuration sections are optional depth, not required reading.

Use it in 60 seconds

Claude Code / Cursor / any MCP client, hosted (EU, no LLM in the loop):

claude mcp add --transport http memory https://memory.primaxiom.ai/mcp \
  --header "Authorization: Bearer rgm_YOUR_KEY"

Python, in-process:

pip install "reasongraph[all]"

from reasongraph import ReasonGraph

graph = ReasonGraph()
graph.initialize_sync()
graph.add_texts_sync(["TSMC is building a chip fab in Phoenix, Arizona.",
                      "Arizona ordered water cuts for industrial users in Maricopa County."])
print(graph.discover_sync("water and chips"))   # a path: water cuts -> Arizona -> TSMC fab

Any language, over HTTP (self-hosted or hosted):

curl -X POST https://memory.primaxiom.ai/sessions/notes/memory \
  -H "Authorization: Bearer rgm_YOUR_KEY" -H "Content-Type: application/json" \
  -d '{"text": "Apple sources M-series chips from TSMC in Arizona."}'

Ready-to-copy agents (Groq/OpenAI-compatible research agent, two agents sharing one memory, Claude Code with persistent memory, LangGraph) live in examples/agents/.

Hosted: ReasonGraph Cloud

memory.primaxiom.ai runs this library as a service: sign in, get a free key (10k requests a month), remote MCP endpoint, browser console and playground. Extraction runs with small models on servers PrimAxiom operates (currently in the EU); facts are only sent to an LLM provider if you ask for a synthesized answer. Early access.

Installation

pip install reasongraph[all]        # everything included

Or install only what you need:

pip install reasongraph             # core: in-memory backend, NER extraction, embeddings
pip install reasongraph[gliner]     # + GLiNER entity extraction + hybrid causal (default, recommended)
pip install reasongraph[causal]     # + SOTA span-pointer causal model (~0.70 F1) + hybrid fallback
pip install reasongraph[gliner2]    # + GLiNER2 alternative (single model does entities + causal)
pip install reasongraph[sqlite]     # + SQLite backend with sqlite-vec
pip install reasongraph[postgres]   # + PostgreSQL + pgvector backend
pip install reasongraph[service]    # + HTTP + MCP memory service
pip install reasongraph[fastembed]  # + pure-ONNX embedder / reranker (faster cold start)

Cross-Source Discovery

Two reports about different topics. Source A covers TSMC's semiconductor plant. Source B covers Arizona's water crisis. Neither mentions the other's subject.

import asyncio
from reasongraph import ReasonGraph

source_a = [  # Tech industry report
    "TSMC announced plans to build a $40 billion semiconductor fabrication plant in Phoenix, Arizona.",
    "The Phoenix fab requires 10 million gallons of purified water daily to cool wafers during the chip etching process.",
    "TSMC signed a long-term supply agreement with Apple to manufacture next-generation M-series processors at the Arizona facility.",
    "Construction delays at the Phoenix site pushed first production to late 2025, raising concerns among TSMC's major customers.",
]

source_b = [  # Environmental report -- never mentions TSMC, semiconductors, or chips
    "Arizona declared a water emergency after Lake Mead dropped to its lowest level since the 1930s, threatening water supply for millions.",
    "The Arizona Department of Water Resources ordered mandatory water cuts for all industrial users in Maricopa County, where Phoenix is located.",
    "Intel paused expansion of its Chandler, Arizona chip plant citing water availability concerns and rising operational costs.",
    "Apple warned investors that component shortages from its Asian and North American suppliers could impact iPhone production timelines through 2026.",
]

async def main():
    async with ReasonGraph() as graph:
        await graph.add_texts(source_a)
        await graph.add_texts(source_b)
        results = await graph.query("How does the Arizona water crisis affect semiconductor manufacturing?")
        for i, text in enumerate(results, 1):
            source = "A" if text in source_a else "B"
            print(f"{i}. [Source {source}] {text}")

asyncio.run(main())

1. [Source B] Intel paused expansion of its Chandler, Arizona chip plant citing water availability concerns and rising operational costs.
2. [Source B] The Arizona Department of Water Resources ordered mandatory water cuts for all industrial users in Maricopa County, where Phoenix is located.
3. [Source A] The Phoenix fab requires 10 million gallons of purified water daily to cool wafers during the chip etching process.
4. [Source B] Arizona declared a water emergency after Lake Mead dropped to its lowest level since the 1930s.
5. [Source A] TSMC announced plans to build a $40 billion semiconductor fabrication plant in Phoenix, Arizona.
6. [Source A] TSMC signed a long-term supply agreement with Apple to manufacture M-series processors at the Arizona facility.

Results come from both sources. No single document contains this chain. Here is what happens under the hood:

ReasonGraph extracts entities and causal relations from each text (requires an entity+causal extractor, e.g. pip install reasongraph[gliner] or [all]):

Three entities appear in both sources, creating bridge nodes:

The query traversal path:

Water crisis query -> finds water-related texts from both sources via embeddings -> follows Arizona and Phoenix entity edges to discover TSMC's water-intensive fab -> follows Apple entity edge from TSMC supply agreement to Apple's component shortage warning. The causal relation Lake Mead dropped -> water emergency connects the environmental trigger to the industrial impact.

Full demo: uv run python examples/cross_source_discovery.py

Quick Start

Using a built-in dataset

from reasongraph import ReasonGraph

graph = ReasonGraph()
graph.initialize_sync()
graph.load_dataset_sync("financial")

results = graph.query_sync("What caused the 2008 financial crisis?")
for i, text in enumerate(results, 1):
    print(f"{i}. {text}")

graph.close_sync()

Output -- a connected reasoning chain, not just keyword matches:

1. Lehman Brothers filed for bankruptcy in September 2008 after massive MBS losses.
2. Loose lending standards fueled a housing price bubble across the United States.
3. Lehman's collapse triggered a global credit freeze as interbank lending stopped.
4. Mortgage-backed securities built on subprime loans collapsed when defaults surged.
5. The U.S. government enacted TARP, a $700 billion bailout to stabilize the financial system.
6. Banks issued subprime mortgages to borrowers with poor credit histories.

Async API

import asyncio
from reasongraph import ReasonGraph

async def main():
    async with ReasonGraph() as graph:
        await graph.load_dataset("financial")
        results = await graph.query("What caused the 2008 crisis?")
        for text in results:
            print(text)

asyncio.run(main())

Features

• Cross-source discovery -- connect facts across independent documents through shared entities and causal relations
• Automatic extraction -- entities (GLiNER gliner_small-v2.5 by default) and cause->effect relations (a dedicated span-pointer / hybrid causal model) are extracted on add, both on by default; falls back to GLiNER2 then BERT NER when gliner is not installed
• Agent memory -- scopes/sessions with cross-session discovery, contradiction resolution (soft-supersede), time-travel (as_of), semantic dedup, and auto-forget
• Causal reasoning -- trace downstream effects, root causes, and directed causal paths; ask counterfactual what_if
• Hybrid search -- combine embedding similarity, keyword (trigram) matching, or both
• Multi-hop traversal -- follow graph edges to discover connected reasoning chains
• Cross-encoder reranking -- rerank results at each hop with ms-marco-MiniLM-L-6-v2
• Memory service -- ready HTTP + MCP server so agents share and query memory
• Built-in datasets -- load curated reasoning graphs for immediate use
• Async-first -- native async API with sync convenience wrappers
• Pluggable backends -- in-memory (zero-config default), SQLite, or PostgreSQL with pgvector

Built-in Datasets

graph.load_dataset_sync("financial")

Search Modes

The default (embedding) is the best general choice and matches hybrid on the eval below; keyword is for known-term lookups. You rarely need to change this.

# Pure embedding similarity (default)
results = graph.query_sync("credit freeze", search_mode="embedding")

# Pure keyword/trigram matching
results = graph.query_sync("credit freeze", search_mode="keyword")

# Hybrid: Reciprocal Rank Fusion of embedding + trigram rankings
results = graph.query_sync("credit freeze", search_mode="hybrid")

# Tune the RRF smoothing constant (default 60, lower = more weight to top ranks)
results = graph.query_sync("credit freeze", search_mode="hybrid", rrf_k=30)

Entity and Causal Extraction

Entity extraction and causal extraction are two independent, both-on-by-default capabilities. add_text() / add_texts() use gliner_small-v2.5 for entities (fast, multilingual, highest entity recall) when gliner is installed, falling back to GLiNER2 then BERT NER. Override per call with the extractor argument -- e.g. gliner_large-v2.5 for higher precision.

from reasongraph import ReasonGraph, NERExtractor, GLiNER2Extractor

graph = ReasonGraph()
graph.initialize_sync()

# Default: GLiNER gliner_small-v2.5 for entities (+ the default causal model),
# falling back to GLiNER2 then BERT NER
entities = graph.add_text_sync("Apple released the iPhone in 2007.")
print(entities)  # ['Apple', 'iPhone']

# Explicit: force BERT NER even if a GLiNER model is installed
entities = graph.add_text_sync("Apple released the iPhone in 2007.", extractor=NERExtractor())

# Explicit: GLiNER2 with custom entity types
gliner = GLiNER2Extractor(entity_types=["company", "product", "date"])
entities = graph.add_text_sync("Apple released the iPhone in 2007.", extractor=gliner)

# Conversational memory: ChatExtractor also captures preference/plan/topic,
# so "hard techno" or "visit" become bridgeable nodes -- not just people/places
from reasongraph import ChatExtractor
entities = graph.add_text_sync(
    "I love hard techno and plan to visit Berlin.", extractor=ChatExtractor()
)  # ['Berlin', 'hard techno', 'visit']

# Any callable works
entities = graph.add_text_sync("some text", extractor=lambda t: ["custom"])

Causal reasoning (default on)

Causality is the headline feature, so causal extraction runs by default (opt out per call with causal=False). Directed cause->effect relations become first-class typed edges (label="causes") in the graph, distinct from anonymous entity bridges, and discover() returns them per fact:

graph.add_text_sync("Heavy rainfall caused severe flooding.")
# -> typed edge  heavy rainfall --causes--> severe flooding

for fact in graph.discover_sync("flooding"):
    print(fact["content"], fact["causes"])  # [{'cause': 'Heavy rainfall', 'effect': 'severe flooding'}]

Causal chain tracing

Because cause->effect edges are directed and first-class, you can walk the causal graph -- something a flat vector store cannot do. Trace downstream impact, trace back to root causes, or find a directed causal path between two facts:

graph.add_texts_sync([
    "Heavy rainfall caused flooding.",
    "Flooding caused power outages.",
    "Power outages caused hospital disruptions.",
])

graph.trace_effects_sync("Heavy rainfall caused flooding.")["terminals"]
# e.g. -> ['hospital disruptions']       # downstream impact

graph.trace_causes_sync("Power outages caused hospital disruptions.")["terminals"]
# e.g. -> ['rainfall']                   # upstream causes (same as root_causes_sync)

graph.causal_chain_sync("Heavy rainfall caused flooding.",
                        "Power outages caused hospital disruptions.")
# -> ordered causal hops, each cited to the fact that asserted it

The exact spans depend on the causal extractor; a hop chains when one fact's effect span matches the next fact's cause span. Each hop is tagged with the fact that asserts it, its scopes, and a cross_session flag; with a conflict_resolver configured, retired (superseded) facts are skipped by default (include_superseded=True keeps them). Tunable with max_depth (default 6) and max_visited (default 1000). Exposed to agents as the trace_memory MCP tool and the /trace HTTP endpoint.

Counterfactual: what breaks if a fact were false

Because the causal edges are first-class, you can ask the inverse of a trace: if one fact were false, which downstream effects collapse? what_if prunes a fact hypothetically (no graph mutation), re-walks reachability, and reports which effect spans lost all causal support versus which survived via an alternate path. Only edges the pruned fact solely supports are removed -- an effect another fact also explains still stands.

graph.what_if_sync("Flooding caused power outages.")
# {
#   'pruned': 'Flooding caused power outages.',
#   'origin': 'Flooding caused power outages.',     # walk start (== pruned unless origin= given)
#   'pruned_edges': [{'cause': 'flooding', 'effect': 'power outages'}],
#   'collapsed': [                                 # lost their only causal path
#       {'span': 'power outages', 'fact': 'Flooding caused power outages.', 'depth': 0, ...},
#       {'span': 'hospital disruptions', 'fact': 'Power outages caused hospital disruptions.', 'depth': 1, ...},
#   ],
#   'survived': [],                                # spans an alternate path rescued
# }

Pass origin= to measure collapse relative to an upstream fact, or direction='causes' to see which upstream causes become orphaned. Exposed as the what_if_memory MCP tool and the /what_if HTTP endpoint.

The default causal extractor picks the best available backend. When the causal-span-model package is installed it uses the span-pointer model (CausalPointerExtractor): a fine-tuned mDeBERTa-v3 that scores ~0.70 F1 on the Causal News Corpus Subtask-2 official scorer -- beating the 0.627 organizer baseline, the hybrid, and a few-shot LLM baseline (~0.24-0.41). It is trained on English but multilingual at inference (script-aware segmentation, verified on es/fr/de/pt/tr/ru/ar and zh/ja) and has a built-in causal gate, so it returns nothing on non-causal text.

Otherwise it falls back to the hybrid (HybridCausalExtractor): a fast, model-free multilingual cue pass handles explicit and reversed phrasing with correct direction, and sentences with no causal connective (implicit causality) fall through to gliner-relex-multi (Apache-2.0, mDeBERTa, ~100 languages). On a four-regime probe set (explicit / multilingual / implicit / reversed) the hybrid reached 100% directed-pair recall vs 61-79% for either part alone -- each covers the other's blind spot -- and most sentences never touch the model, so the average cost is low. Reproduce with tests/bench_causal_extractors.py.

from reasongraph import CausalPointerExtractor, HybridCausalExtractor, GlinerRelexExtractor

ReasonGraph()                                          # best available (pointer if installed, else hybrid)
ReasonGraph(causal_extractor=CausalPointerExtractor())  # force the span-pointer model
ReasonGraph(causal_extractor=HybridCausalExtractor())  # force the hybrid
ReasonGraph(causal_extractor=GlinerRelexExtractor())   # relex model only
ReasonGraph(causal_extractor=False)                    # disable causal extraction

pip install reasongraph[causal] installs both the pointer model (causal-span-model) and the hybrid (gliner), so the graph uses the SOTA pointer by default and falls back to the hybrid automatically. If neither is available the default warns once rather than silently dropping causality; add_text(..., causal=True) raises when no causal extractor can be resolved.

Fast inference (optional, pure ONNX)

The defaults already deliver the eval quality below; this is purely a speed/memory optimization. Every model slot is pluggable, so you can trade the PyTorch defaults for CPU-optimized ONNX models at equal-or-better quality. Measured on the 32-case mixed-domain eval:

from reasongraph import ReasonGraph, FastEmbedEmbedder, FastEmbedReranker

graph = ReasonGraph(
    embed_model=FastEmbedEmbedder("sentence-transformers/all-MiniLM-L6-v2"),
    rerank_model=FastEmbedReranker("Xenova/ms-marco-MiniLM-L-6-v2"),
)

• Reranker → Xenova/ms-marco-MiniLM-L-6-v2: the ONNX build of the default reranker, so scores (and eval quality) are identical, but cold start drops from ~2.4s to ~0.03s.
• Embedder → all-MiniLM-L6-v2 (ONNX): ~2.3x faster load, equal-or-better eval quality.
• Full ONNX pipeline: ~3x faster cold start and ~23% less RAM at equal-or-better quality; per-query latency rises (~12ms to ~100ms), a good trade when cold start and memory matter more than warm latency.
• Multilingual embedder (paraphrase-multilingual-MiniLM-L12-v2) is available as an option; it costs a few points of English quality.

Requires pip install reasongraph[fastembed]. Benchmark any configuration with tests/bench_pipeline.py.

Choosing an extractor (optional)

You don't need to choose -- the default (gliner_small-v2.5 for entities plus the default causal model) is the recommended, benchmarked setup. This section is the evidence behind that default and the alternatives for special cases; swap the entity model with the extractor argument if you have a specific need (reproduce the numbers with tests/bench_extractors.py):

• GlinerExtractor (default) -- GLiNER v1 zero-shot with convert-and-cache ONNX inference (fast, flexible entity types; entities only -- causal relations come from the separate default causal model). Defaults to gliner-community/gliner_small-v2.5, which on a 10-language WikiANN benchmark led on entity recall (86%, vs GLiNER2's 74%) at ~67 ms/call and ~2.2 GB -- and unlike GLiNER2 it holds up on Korean/Arabic/Turkish/Russian. The checkpoint matters a lot: the older urchade/gliner_multi-v2.1 scores ~12%, so pin the model and benchmark with tests/bench_ner_multilingual.py.
• GLiNER2Extractor -- a single model that does entity types and causal relations in one pass. Reach for it when you want one model for both, but it is the heaviest (loads slowly, ~4.6 GB) and lower on multilingual entity recall.
• OnnxTokenClassifierExtractor -- runs any BIO token-classification model exported to ONNX, decoding entities from the model's own id2label. Fast (~30 ms/call) and multilingual with a suitable model; the label scheme is the model's, so a specialized place model or a custom general NER both drop in with no code change.

Size sweep (same WikiANN benchmark) -- bigger is not uniformly better:

Small ties large on recall; large's extra size buys precision (best F1). Medium is dominated -- skip it. large-v2.5 beats GLiNER2 outright (same precision, higher recall, faster, far stronger on Arabic/Korean). knowledgator/gliner-x-base (20+ languages) edges recall/precision above small-v2.5 but needs stanza + langdetect (with per-language models fetched at runtime), runs ~7x slower, and is no better on the WikiANN Chinese reconstruction -- so small-v2.5 stays the default; reach for x-base only when precision matters more than latency.

Running gliner_small-v2.5 through ONNX (GlinerExtractor(onnx=True)) cuts inference from ~67 ms to ~12 ms/call with recall preserved -- the fastest high-recall multilingual option (the conversion is cached on first use).

Rough guide: gliner_small-v2.5 for the best speed/RAM at high recall (add onnx=True for ~12 ms/call); gliner_large-v2.5 for the best overall quality and a strict upgrade over GLiNER2 on multilingual; GLiNER2 only when you need its causal-relation extraction; place ONNX for the fastest location-heavy path.

Scopes

Scopes are free-text tags on facts ("user-alice", "topic-economy", "session-42") -- not partitions. The graph stays shared: a fact can carry several scopes at once, and multi-hop reasoning follows shared entities across every scope. A scope on query() only narrows where the search seeds; traversal still reaches connected facts in other scopes.

await graph.add_texts(alice_facts, scopes=["user-alice"])
await graph.add_texts(economy_facts, scopes=["topic-economy"])
# One fact can belong to several scopes at once
await graph.add_texts(shared, scopes=["user-alice", "topic-economy"])

# Seeds come from user-alice; reasoning still bridges into topic-economy facts
results = await graph.query("Will it get harder to afford a home?", scopes=["user-alice"])

Adding the same content under a new scope unions the tags (never drops the old ones). For a hard boundary where a query can only reach its own scope's facts, pass isolate=True (see Multi-tenant and production). Full demo: uv run python examples/scoped_reasoning.py

Backends

By default, ReasonGraph() uses a pure Python in-memory backend (MemoryBackend). This works everywhere with zero dependencies beyond numpy. For persistence, pass a file path to save/load as JSON:

from reasongraph import ReasonGraph, MemoryBackend

# In-memory only (default)
graph = ReasonGraph()

# In-memory with JSON file persistence (loads on init, saves on close)
graph = ReasonGraph(backend=MemoryBackend(file_path="graph.json"))

SQLite Backend

For larger graphs or concurrent access, use the SQLite backend with sqlite-vec for vector search. Requires pip install reasongraph[sqlite].

from reasongraph import ReasonGraph
from reasongraph.backends import SqliteBackend

graph = ReasonGraph(backend=SqliteBackend(db_path="graph.db"))

PostgreSQL Backend

from reasongraph import ReasonGraph
from reasongraph.backends import PostgresBackend

graph = ReasonGraph(backend=PostgresBackend(database_url="postgresql://user:pass@localhost/db"))

Requires pip install reasongraph[postgres] and the pgvector + pg_trgm extensions enabled on your database.

Evaluation: Mixed-Domain Reasoning

We evaluate reasoning quality by loading all 6 built-in datasets into a single graph (~130 text nodes, ~104 entity nodes, ~280 edges) and testing whether the library can trace the correct causal chains, syllogistic proofs, taxonomic hierarchies, and data analysis patterns -- without being distracted by unrelated facts from other domains.

32 test cases simulate agent-style queries like "I need to understand what caused the 2008 financial crisis", "How does insulin resistance lead to kidney failure?", or "I have two numeric columns, check if related" and check whether the returned reasoning chain matches the expected ground truth.

Per-domain results (hybrid search, top_k=5, hops=4, rerank_top_k=4):

32/32 cases pass (>= 50% chain completeness). Split reranking gives chain continuations (text-to-text edges) priority over bridge discoveries (entity-to-text edges), keeping traversal focused.

Search mode comparison:

Keyword-only mode scores 0% because the eval queries are natural language questions that don't substring-match the dataset's declarative statements. This is expected -- keyword search is designed for known-term lookups, not question answering.

Reproduce: uv run python tests/eval_financial_reasoning.py

API Reference

ReasonGraph(backend=None, embed_model=None, rerank_model=None, forget_after=30, forget_every=None, synthesizer=None, causal_extractor=None, isolate_traversal=False, conflict_resolver=None)

• causal_extractor: None builds the best available causal extractor lazily (the span-pointer model when causal-span-model is installed, else the hybrid); False disables causal extraction; a callable/object with extract_causal uses it.
• isolate_traversal: graph-wide default for whether a scoped query confines traversal to its scopes (multi-tenant). Off keeps cross-scope discovery; override per call with query(..., isolate=...).
• conflict_resolver: enables contradiction resolution (soft-supersede) on write and retired-fact filtering on read (see Multi-tenant and production).

Ingest

Retrieve

Causal reasoning

Update, forget, temporal

Datasets and inspection

Lifecycle is initialize() / close(), or use async with ReasonGraph() as graph:. All methods are async; every one has a _sync twin with the same parameters (e.g. query_sync, what_if_sync, add_text_sync).

embed_model accepts a model name (str), a SentenceTransformer, or any object/callable that encodes text. The encoder must take a str (returning one vector) or a list[str] (returning one vector per text); numpy, torch, or list outputs are all accepted. This lets a host reuse an embedder it already runs instead of loading a second stack:

def encode(text_or_texts):
    # reuse your own embedding library; return list[float] or list[list[float]]
    ...

graph = ReasonGraph(embed_model=encode)

Agent memory service

A ready service turns reasongraph into shared, discoverable memory for many agents. Knowledge sessions are scopes: an agent pushes memory into its session, and a query seeds from that session but traversal crosses all sessions -- so agents discover connections into each other's memory through shared entities. pip install reasongraph[service].

from reasongraph.service import MemoryService
from reasongraph.backends import PostgresBackend

service = MemoryService(backend=PostgresBackend("postgresql:///memory"),
                        synthesizer=my_small_llm)   # synthesizer is optional

await service.push("research-bot", "TSMC is building a chip fab in Arizona.")
await service.push("news-bot", "Arizona declared a water emergency.")

# research-bot discovers news-bot's fact via the shared 'Arizona' entity
paths = await service.discover("Arizona", session="research-bot")
answer = await service.answer("Arizona", session="research-bot")   # logical free text

Expose it over HTTP (reasongraph.service.http.create_app) or MCP (reasongraph.service.mcp_server.create_mcp) -- the HTTP query/discover endpoints take a synthesize flag that adds the free-text answer. The demo uv run python examples/agent_memory_service.py pushes an economy / supply-chain / energy / health / policy world across five agent sessions and shows a markets query reaching a Taiwan drought and a chip fab recorded by other agents.

HTTP endpoints: POST /sessions/{session}/memory (and /batch; pass resolve_conflicts: true to check nearby facts for contradictions), /query (supports as_of and include_superseded for time-travel), /discover, /causal_chain, /supersede, /delete, /history, /trace, /what_if, /forget, GET /sessions, /stats, plus /health and /ready probes.

MCP tools: push_memory, query_memory, query_memory_detailed, discover_connections, causal_chain_memory, trace_memory, what_if_memory, answer, update_memory, delete_memory, memory_history, forget_stale, list_sessions.

Synthesizers

answer() and the synthesize flag rephrase retrieved facts and their connection paths into logical free text. The core stays model-free -- pass any callable(query, context) -> str, or one of the shipped adapters:

from reasongraph import TemplateSynthesizer, PromptSynthesizer, TransformersSynthesizer

ReasonGraph(synthesizer=TemplateSynthesizer())            # deterministic, no model
ReasonGraph(synthesizer=PromptSynthesizer(my_generate))   # bring any LLM: generate(prompt) -> str
ReasonGraph(synthesizer=TransformersSynthesizer())        # local small LLM (Qwen2.5-0.5B-Instruct)

PromptSynthesizer builds the prompt (question + facts + cross-session bridges) and calls your generate (sync or async); TransformersSynthesizer runs a small instruct model locally on the torch/transformers stack already pulled in by sentence-transformers.

Deploy

An env-driven entrypoint wires the backend, embedder, and synthesizer from environment variables. Run the Postgres-backed stack with Docker:

docker compose up --build          # Postgres (pgvector) + the service on :8000
curl localhost:8000/stats

Or serve directly (pip install reasongraph[service] adds the reasongraph-serve console script and the ASGI factory):

REASONGRAPH_BACKEND=postgres \
REASONGRAPH_DATABASE_URL=postgresql:///memory \
REASONGRAPH_SYNTHESIZER=template \
reasongraph-serve            # or: uvicorn reasongraph.service.app:create_app_from_env --factory

Use a persistent backend (PostgresBackend) for real multi-agent concurrency.

Multi-tenant and production

By default the graph is shared: a scoped query seeds from its session but the walk crosses sessions, which is the cross-session discovery feature. For a confidentiality boundary between tenants, turn on traversal isolation so a query can only reach its own session's facts:

ReasonGraph(isolate_traversal=True)               # graph-wide default
graph.query("...", scopes={"tenant-a"}, isolate=True)   # or per query

Other production controls:

• Auth: create_app(service, api_key="...") (or REASONGRAPH_API_KEY) gates every data endpoint; the MCP server exposes the same tools.
• Structured results: query_detailed(...) (and the HTTP detailed flag / query_memory_detailed MCP tool) return {content, score, created_at, scopes} for thresholding, dedup, and "remembered on ".
• Erasure: delete(content, purge_orphans=True) / supersede(..., purge_orphans=True) also remove entities left dangling by the deletion (right-to-be-forgotten); shared entities survive. Exposed as delete_memory / update_memory MCP tools.
• Semantic dedup: add_text(..., dedup_threshold=0.95) drops near-duplicate restatements instead of accumulating them, unioning scopes onto the kept fact.
• Contradiction resolution: ReasonGraph(conflict_resolver=NLIConflictResolver()) (or REASONGRAPH_RESOLVE_CONFLICTS=1) soft-supersedes facts a new one contradicts -- a supersedes edge drops the old fact from default query/discover recall while keeping it auditable and retrievable via include_superseded=True; supersession_history(fact) shows what replaced what. The resolver is pluggable (any object with contradictions(new, candidates)): the NLIConflictResolver cross-encoder needs no LLM but can over-flag complements (it treats "works in Munich" vs "lives in Berlin" as a conflict), while LLMConflictResolver(generate) brings any LLM and is more precise. Soft-supersede is deliberately reversible: re-asserting a fact revives it, and query(..., as_of=<datetime>) time-travels to what was current at that moment (each fact carries a created_at/invalid_at validity interval). Exposed to agents as the memory_history MCP tool and /history endpoint.
• Health: /health (liveness) and /ready (readiness) for orchestration probes.
• Postgres creates an HNSW cosine index, so vector search is index-accelerated rather than a sequential scan.
• Speed: tests/bench_speed.py measures write throughput and read latency (query / discover / trace, p50/p95) at a configurable graph size and backend (--fake for model-free timing). Indicative real-model, in-memory numbers: query ~14ms, discover ~7ms, causal trace ~3ms p50.

License

MIT