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"

Local MCP server (stdio, everything on your machine, SQLite):

pip install "reasongraph[service,gliner,fastembed,sqlite]"
claude mcp add memory -- reasongraph-mcp

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.

JavaScript and TypeScript

Agents that are not written in Python talk to the hosted service through a dependency-free client (clients/typescript). It uses the platform fetch, so it runs on Node 18+, Bun, Deno, Cloudflare Workers and the browser. npm install reasongraph.

import { Memory, memoryTools } from "reasongraph";

const mem = new Memory({ apiKey: process.env.REASONGRAPH_API_KEY });
await mem.remember("scout", "TSMC is building a chip fab in Phoenix, Arizona.");
const facts = await mem.discover("What could disrupt the Phoenix fab?");

memoryTools(mem) returns OpenAI-style tool definitions with their executors attached, for agents that call functions directly without a framework: remember, recall and why.

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]):

Text (abbreviated)	Entities	Causal relations
TSMC to build fab in Phoenix, Arizona...	TSMC, Phoenix, Arizona	--
Phoenix fab requires 10M gallons water...	Phoenix	--
TSMC supply agreement with Apple...	TSMC, Apple, Arizona	--
Construction delays at Phoenix site...	TSMC, Phoenix	Construction delays -> first production
Arizona water emergency, Lake Mead...	Arizona, Lake Mead	Lake Mead dropped -> water emergency
Mandatory water cuts in Maricopa County...	Arizona Dept. of Water Resources, Phoenix, Maricopa County	--
Intel paused Arizona chip plant...	Intel, Chandler, Arizona	--
Apple warned of component shortages...	Apple	component shortages -> iPhone production timelines

Three entities appear in both sources, creating bridge nodes:

Bridge entity	Source A connections	Source B connections
Arizona	TSMC fab, TSMC-Apple deal	water emergency, Intel pause, water cuts
Phoenix	TSMC fab, water usage, delays	water cuts for industrial users
Apple	TSMC supply agreement	component shortage warning

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 a cross-encoder (ms-marco-MiniLM-L-6-v2 by default, multilingual mMARCO in the hosted service)
• 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

Causal eval cases

tests/data/causal_cases.jsonl (40 reviewed cases), tests/data/causal_cases_batch2.jsonl (40 more, 8 domains x 5, 12 non-English) tests/data/causal_cases_batch3.jsonl (60 more: 20 each German, Spanish, French) and tests/data/causal_cases_batch4_trnl.jsonl (20 Turkish, 20 Dutch) each hold multi-source why-questions with a gold chain. Run python tests/eval_causal_cases.py --cases tests/data/causal_cases_batch2.jsonl. Baseline on batch2 with the default models: chain recovered 100%, ordered 47%, answer 100%, causal chain 65%.

Models

Every model slot is pluggable; these are the defaults and what ReasonGraph Cloud runs. All of them are small and run on CPU.

Step	Library default	ReasonGraph Cloud	Notes
Sentence splitting	off (split="sat" or "regex" to enable)	SaT sat-3l-sm (wtpsplit)	84% boundary recovery on messy text vs 40% for the regex splitter
Entities	GLiNER gliner-community/gliner_small-v2.5	same	zero-shot, multilingual; 97% recall on a 6-language check, ~19 ms/call. REASONGRAPH_ENTITY_NORMALIZE=1 (or canonicalizer=EntityNormalizer()) merges surface forms ("Sabah"/"sabah", "Bulk Export's"/"Bulk Export") into one node, and REASONGRAPH_ENTITY_CONTAINMENT=1 (or link_contained_entities=True) also links a fact to an existing entity that its entity whole-word-prefixes or extends ("malzeme" / "malzeme eksikliği"), through an indexed first-word lookup. Both are off by default: measured on the 80-case busy-tenant eval they gave no root-recall gain and containment linked across unrelated cases 79% of the time; they remain for experiments
Cause → effect	Berk/causal-span-pointer-v2 (fine-tuned mDeBERTa-v3, open weights)	v3 (private for now; purpose-clause direction 97% vs 20%, CNC 0.705), plus its token gate at threshold 0.1	0.70 F1 on CausalNewsCorpus dev; the gate keeps plain statements out of the causal graph. REASONGRAPH_CAUSAL_ONNX=hf://owner/repo/file.onnx runs the same model through onnxruntime, 2x faster on CPU with identical spans
Embeddings	all-MiniLM-L12-v2	paraphrase-multilingual-MiniLM-L12-v2 (fastembed)	switch when your facts are not only English
Span linking	embedding cosine ≥ span_link_threshold (0.85)	a span-link cross-encoder (REASONGRAPH_SPAN_LINKER, logit ≥ REASONGRAPH_SPAN_LINK_LOGIT) once measured; ties paraphrased hops cosine misses (17/20 vs 7/20 recovered at zero false links on held-out cases)
Reranker	cross-encoder/ms-marco-MiniLM-L-6-v2	cross-encoder/mmarco-mMiniLMv2-L12-H384-v1	the multilingual reranker lifted German discovery from 62% to 88% in our eval
Contradiction check	off (resolve_conflicts=True needs a resolver)	Berk/reasongraph-extractor-1.7b (fine-tuned Qwen3 1.7B, open weights) on llama.cpp, with an embedding pre-filter	0.95 F1 on the hand-checked pairs; ~0.4 s per pair on two CPU threads
Chat / written answers	none (bring your own call_model)	an outside provider, currently gpt-oss-120b on Groq	the only step that uses a large model, and only when you use chat or ask for an answer

Evaluation scripts for each slot are in tests/ (eval_causal_extraction.py, eval_causal_cases.py) and results are quoted next to the options below.

Built-in Datasets

Dataset	Description
syllogisms	Classical syllogistic reasoning chains
causal	Cause-effect reasoning with entity annotations
taxonomy	Hierarchical concept taxonomy
financial	Financial crisis causal chains (2008 crisis, dot-com, inflation, eurozone)
medical	Medical causal chains (heart disease, diabetes, infectious disease, cancer)
analysis_patterns	Data analysis reasoning: scenario detection, technique selection, implementation patterns

graph.load_dataset_sync("financial")

Search Modes

embedding (the default) finds seeds by meaning. hybrid fuses that with a word-level trigram channel (pg_trgm strict word similarity, index-assisted on Postgres): a name, a code, a number or a compound in the question matches the fact that contains it even when the embedder never saw the word. keyword is the trigram channel alone, for known-term lookups. The memory loop takes the same option (MemoryLoop(search_mode="hybrid"), or REASONGRAPH_LOOP_SEARCH=hybrid), and stays embedding by default.

Measured, so you do not have to guess: on the causal-root eval (180 cases, six languages, one busy tenant) hybrid does not help and slightly hurts: root recall 9% -> 7%, English 15% -> 8%, p95 latency +22%. The reason is structural, not a tuning failure: a root cause is phrased nothing like the question, so matching the question's words surfaces mid-chain filler that then competes for the context budget. Hybrid's own case (exact names, codes, part numbers, identifiers) is real but is a lookup task, which that eval does not measure. Turn it on for lookup-shaped workloads; leave it off for "why" questions.

How far the walk goes, and in which direction

hops bounds the walk's depth. causal_hops=(forward, backward) bounds it per direction: forward follows cause -> effect (consequences), backward follows effect -> cause (what led here). Entity bridges are unaffected. "Why" is a backward question, so a walk that spends its depth asymmetrically can reach a root cause a symmetric one misses:

loop = MemoryLoop(graph, session="chat", causal_hops=(3, 2))   # or REASONGRAPH_CAUSAL_HOPS=3,2

The default is symmetric (None), and on our own causal eval the split makes no difference at all: no path there runs more than two causal edges in one direction before the overall hops limit binds, so a per-direction cap never fires. Reach for this only when your graph has genuinely long one-directional chains, four or more hops of pure cause-to-cause. Raising hops itself was also measured: depth 5 buys two more correct answers in 180 for roughly twice the database work, which is why the default stays 3.

Linking two wordings of one event

The same event turns up written two ways: "costs were reduced" in one sentence, "the cost reduction" in the next. Cosine over a general retrieval embedder does not put those together, and when it fails the causal chain breaks, which is measurably where root causes get lost.

That decision is its own job, so it can use its own model. span_linker accepts either shape:

ReasonGraph(span_linker="bi:my-org/same-event-multilingual")   # a similarity model, scored by cosine
ReasonGraph(span_linker="my-org/same-event-cross-encoder")     # a cross-encoder, scored pairwise

or REASONGRAPH_SPAN_LINKER with the same values. Both see only direction-aware candidates: an effect span is only ever compared with a cause span. span_link_top_k sets how many near neighbours a span is compared against before anything judges them. It defaults to 6. It used to widen to 10 whenever a linker was configured, and that was measurably wrong: on 341 cases the wider shortlist floods the walk with look-alikes, halving the gain on rephrased chains and turning a small gain on ordinary chains into a small loss. Narrowing it back was the single largest improvement in this whole line of work, and it costs nothing.

By default a linker replaces the embedder's own cosine, which means it can also lose links cosine was right about. span_link_floor makes it add instead: cosine keeps every link it would have made, and the linker only speaks for pairs whose cosine falls in the band between the floor and the threshold.

ReasonGraph(span_linker="bi:my-org/same-event", span_link_floor=0.6)   # or REASONGRAPH_SPAN_LINK_FLOOR

On our own corpus the floor turned out to be a no-op at every setting: within the linker's candidate set, cosine and the trained model never disagree in the band the floor arbitrates, so there is nothing for it to keep or cut. It stays available because another corpus may well contain that disagreement, but do not expect it to help without measuring.

Keeping a long conversation inside its context window

Three things hold a long chat together: the recent messages verbatim, a summary of what came before, and recall of anything older that turns out to be relevant. The loop does the third by default, and the first two are configured on the session.

loop = MemoryLoop(
    graph, session="support-chat",
    max_history_tokens=6000,        # fold once the transcript passes this
    keep_tail_tokens=2000,          # this much of the newest talk stays word for word
    summarizer=my_model,            # fn(messages, max_tokens=None) -> str; omit and old turns are dropped
    summary_length_target=False,    # cap the summary at its share of the budget; costs detail
    summarize_in_background=True,   # summarise after the reply, never before it
)

Why a token budget rather than the last N messages. A fixed count is wrong in both directions: ten one-line exchanges are nothing, and ten pasted stack traces overflow the window. The budget counts what actually costs you.

Why fold a block at a time. When the transcript outgrows the budget, everything older than the tail becomes one summary and the tail stays verbatim. Summarising a block rather than a message means the summarizer runs rarely, and a conversation that never reaches the budget never summarises at all. The next fold takes the previous summary in with the newly-aged messages, so summaries merge instead of stacking.

What the summary costs, and why it is not capped by default. The summary and the verbatim tail share max_history_tokens, so what is left once the tail is counted is the room the summary has: loop.summary_budget_tokens. Nothing makes the model respect it. Measured on qwen2.5 7B over eight folds with a 110-token share, keeping a list of 17 details that a later reply could need:

	summary after 8 folds	details kept
no length asked for (default)	374 tokens	17 of 17
summary_length_target=True	228 tokens	11 of 17

Told a length, the model holds near it and drops detail to get there; told nothing, it keeps everything and overruns its share instead. Neither is free, so the choice is yours: the default keeps the detail, and summary_length_target=True passes summary_budget_tokens to the summarizer as max_tokens when the prompt has to fit. A summarizer that takes only messages still works either way. One model, one transcript, one seed — worth re-measuring on yours.

The summarizer is never on the hot path. Folding uses the summary the session already has and records what still needs summarising. With summarize_in_background the work happens after the reply is sent, so the summary lands one turn later; without it the fold waits. Either way a summarizer that is slow, down, or returns nothing leaves the conversation working, because losing the wording of old turns is survivable and stalling the answer is not.

What a summary is not. It is a model's paraphrase with no source behind it, so it arrives as its own system message and never mixes with the recalled facts, which carry theirs. And it matters less here than elsewhere: messages that fall out of the window were stored as facts by observe, so they come back by meaning when they are relevant. The summary is for continuity, not for remembering.

Notes that point backwards

People chain causes by pointing rather than repeating: "this broke checkout", "because of that we rolled back". Extraction reads one sentence at a time, so "this" refers to nothing it can see and the link is lost. On real incident write-ups about a fifth of the causal links between sentences are of this kind.

ReasonGraph(resolve_back_references=True)   # or REASONGRAPH_RESOLVE_BACK_REFERENCES=1

A sentence that opens with a back-reference and asserts a cause is linked to the note before it. The device differs by language and is often not a pronoun at all: German and Dutch carry the reference inside an adverb ("dadurch", "daardoor"), Turkish marks it with case endings ("bu nedenle", "bundan dolayı"), and a connective like "as a result" or "por ello" asserts the link on its own.

Off by default, and here is the honest state. On generated cases it recovers a third of these otherwise lost links with no wrong links at all, and it changes nothing on the standing evaluation. What is not established is its precision on ordinary traffic, so turn it on deliberately and check. Two limits no rule can fix: Spanish and Turkish often drop the subject entirely, leaving no marker to find, and Turkish tends to express cause inside a single sentence, so it has less of this to recover in the first place.

Measured, so you can skip what we tried. A general cross-encoder scored below plain cosine. A purpose-trained same-event model, on the other hand, triples root-cause recall on exactly the cases where the two sides are phrased differently (1.6% to 4.9%), while slightly hurting the cases that never needed it (6.0% to 5.0%). Whether that trade is worth it depends on your text: it breaks even when about a quarter of your causal links are phrased differently on each side, and in ordinary domain notes roughly two-thirds are, so it usually pays about three times over. Measure your own mix before assuming it.

Repeatable answers at scale

Measured on a 100k-fact tenant, and the answer is reassuring: a running service is already repeatable. Ask the same question twice against the same index and you get the same facts, every time, on every version. The order within a result is fixed too, at no cost.

What drifts is a rebuild. Two indexes built independently over the same data return slightly different neighbours, because the search is approximate. On that tenant, 30 of 80 questions differed between two fresh builds, and 4 of those changed the root cause itself, so it is not merely cosmetic.

Making two rebuilds agree requires exact search, which costs roughly 3.6x on recall latency. That is a migration setting, not a serving one:

REASONGRAPH_PG_DETERMINISTIC=1     # exact search: rebuild-stable, much slower
REASONGRAPH_PG_EF_SEARCH=<n>       # a wider candidate window, if you want it too

Leave both off for serving. Turn the first on when you rebuild a store and need the answers to match the one it replaces.

Walking in levels

A recall walks the graph outward from its seeds. Each level is fetched in one backend call (nearest_neighbors_many), not one call per node, because over a network a recall's cost is its round trips: measured at 110 round trips per recall, a 5 ms hop to the database nearly quadrupled recall latency. Backends that cannot batch inherit a default that loops, so this is transparent.

Within one recall, a fact's scopes, causal relations and timestamps are fetched once (ReasonGraph.request_cache(), opened by MemoryLoop.recall): a recall makes several passes over overlapping facts, and over a network every repeat is a round trip. The cache is dropped when the request ends, so nothing is stale across requests, and only read-only metadata is memoised.

Concurrency, for deployments that run several writers (an API plus extraction workers): node and edge upserts are ordered by key so writers cannot deadlock on the same rows, schema creation is serialised with an advisory lock, and transient write failures (deadlock, serialization failure, an aborted pipeline) are retried with backoff.

# 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.

The built-in gate can be replaced by a decoupled embedding gate: a small classifier on sentence embeddings (train one with scripts/train_embed_gate.py in causal-span-model; it saves a .joblib). It costs a millisecond per sentence, is retrained on any negative mix without touching the span heads, and on our causal eval it gave fewer, more precise edges than the built-in gate. Pass a local path or an hf://owner/repo/file.joblib reference:

ReasonGraph(causal_extractor=CausalPointerExtractor(
    model="Berk/causal-span-pointer-v2", gate_threshold=1.0,          # built-in gate off
    embed_gate="hf://Berk/causal-span-pointer-v2/embed_gate_mlp.joblib",
    embed_gate_threshold=0.9))                                        # keep P(causal) >= 0.9

causal_chain also bridges facts that phrase one event differently ("the system throttles performance" -> "Throttling performance", or a plain root fact whose words reappear in the next cause span), so directed chains survive wording changes even without span_link_threshold. trace_causes(..., bridge=True) walks back the same way: from a cause span to the effect spans of other facts that name its event ("the billing job ran twice whenever a payment retried" -> "The billing job ran twice"), and from a plain fact with no relation of its own to the effect spans that describe it, so a symptom someone noted ("the billing job started double-charging") leads to the explanation recorded later.

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.

Sentence splitting at ingest

Every model in the pipeline is trained on single sentences, so a paragraph pushed as one fact hurts entities, causal spans and retrieval alike (on our 39-case causal eval, chain recall drops from 79% to 10%). Pass a splitter and each text becomes one fact per sentence:

ReasonGraph(sentence_splitter="sat")          # Segment-any-Text, 85 languages: pip install reasongraph[split]
ReasonGraph(sentence_splitter="regex")        # dependency-free fallback (punctuation + newlines)
graph.add_texts([paragraph], split=True)      # or per call; split=False keeps a text whole

The service reads REASONGRAPH_SPLIT_SENTENCES=sat|regex; pushes accept split: true/false.

Deep memory integration: the memory loop

No tools, no prompts to write: wrap any chat model and every exchange becomes memory, and whatever is relevant comes back by itself before the next call.

from reasongraph import ReasonGraph, MemoryLoop

graph = ReasonGraph()                                  # or your Postgres-backed graph
loop = MemoryLoop(graph, session="support-chat", max_facts=8)

history = [{"role": "user", "content": "Why did the Rotterdam warehouse lose power?"}]
reply, context = loop.chat_sync(call_model, history, system="You are a careful assistant.")
# call_model is any fn(messages) -> str: OpenAI-compatible, Claude, Ollama, llama.cpp
# context.facts  -> what was recalled (with sources and cause->effect links)
# context.roots  -> for why-questions, the root cause(s) the chain walks back to;
#                   they are spelled out in the injected block so a small model
#                   answers with the root, not only the nearest cause
# the question and the reply are now remembered in "support-chat"

The loop also remembers the conversation itself. Those stored turns are recalled like any other fact, but judged after everything else: the question you just asked and an earlier "I don't know" would otherwise score highest and take every slot. graph.forget(scopes) erases a session (or a tenant, or a test run): facts and the entities only they linked are deleted; a sentence also held elsewhere is detached, not deleted.

loop.messages(history) returns the message list with the recalled facts injected as a system message, if you want to call the model yourself; loop.observe(user, assistant) stores an exchange. Options: max_facts / max_chars (context budget), min_score (no unrelated filler), rerank_min (an optional cross-encoder cutoff on top of it: cosine cannot tell "same topic" from "answers this", the reranker can; -4 with the default reranker), extend_query (when a why-question's chain ends in a root cause no recalled fact states, one more targeted query fetches the plain fact behind it), bridge_causes (on by default: the causal trace crosses facts that word one event differently and starts from a plain symptom, which is what a vague question such as "anything to watch before the next billing run?" seeds; on a busy 15-incident memory that took the root cause from 33% to 73% of such questions with the small production embedder), observe_user / observe_assistant, redact (a function that drops or rewrites text before it is stored), resolve_conflicts. The hosted service exposes the same loop as POST /chat. Example agent: examples/agents/memory_loop_agent.py.

LangChain and LangGraph

pip install langchain-reasongraph (the LangChain partner-style package, with LangChain's standard retriever tests; source in packages/langchain-reasongraph) or pip install "reasongraph[langchain]" adds three adapters that work with a local ReasonGraph or the hosted service through reasongraph.client.MemoryClient:

from reasongraph.integrations.langchain import ReasonGraphRetriever, with_memory, memory_tools

retriever = ReasonGraphRetriever(target=graph)          # documents = the facts the graph connects
model = with_memory(ChatOpenAI(...), graph, session="support-chat")   # recall in, exchange remembered
tools = memory_tools(graph, session="agent")            # remember / recall / discover for agents

Documents carry the sources, the names the fact was reached through and its cause->effect links in metadata. Full example: examples/agents/langchain_memory.py; a LangGraph agent that uses the tools: examples/agents/langgraph_agent.py.

A memory class for chains and agents

ReasonGraphMemory is the classic BaseMemory shape (load_memory_variables / save_context), so it drops in wherever a LangChain memory goes. Each turn the agent sees two things: memory, the facts the graph connects to the input with their sources and cause->effect links, and history, the transcript folded to a token budget with the oldest turns as one rolling summary and the newest verbatim.

from reasongraph.integrations.langchain import ReasonGraphMemory
from reasongraph.loop import make_summarizer

memory = ReasonGraphMemory(target=graph, session="ops-chat",
                           max_history_tokens=2000, keep_tail_tokens=800,
                           summarizer=make_summarizer(lambda msgs: llm.invoke(msgs).content))

seen = memory.load_memory_variables({"input": "Which version is staging on, and why?"})
seen["memory"]    # "- We rolled staging back to 2.3.1 because the certificate expired. [ops-chat]\n  because: ..."
seen["history"]   # "Summary: ...\nHuman: How do I speed up rollbacks?\nAI: Keep the previous image warm..."
memory.save_context({"input": "..."}, {"output": "..."})

Folding decides what the model sees and deletes nothing: a turn that left the window is still a fact and comes back through memory when it is relevant again. The summary is written after save_context, never in the middle of a turn, and without a summarizer the budget still holds. ReasonGraphChatMessageHistory offers the same transcript as a BaseChatMessageHistory for RunnableWithMessageHistory. Walkthrough with what the agent sees at every turn: examples/agents/langchain_memory_class.py.

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:

model	infer	RAM	recall	prec	F1
gliner_small-v2.5	67 ms	2.2 GB	86%	73%	79%
gliner_medium-v2.5	73 ms	2.7 GB	84%	75%	79%
gliner_large-v2.5	142 ms	4.8 GB	86%	84%	85%
knowledgator/gliner-x-base	151 ms	4.2 GB	87%	79%	83%
GLiNER2	250 ms	4.8 GB	74%	84%	79%

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):

Domain	Cases	Chain Completeness	Recall@5	Precision@5	Domain Accuracy
Causal	5	100%	100%	92%	100%
Financial	6	100%	82%	60%	100%
Medical	5	100%	92%	76%	92%
Syllogisms	5	100%	100%	92%	85%
Taxonomy	3	100%	83%	53%	92%
Analysis Patterns	8	96%	75%	45%	96%
Overall	32	99%	88%	68%	95%

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:

Mode	Chain Completeness	Recall@5	Precision@5	Domain Accuracy
Embedding	99%	88%	68%	95%
Keyword	0%	0%	0%	0%
Hybrid	99%	88%	68%	95%

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

Method	Description
add_nodes(nodes, scopes=None)	Add (content, type) tuples to the graph
add_edges(edges)	Add (from, to) or (from, to, label) content edges (label e.g. "causes")
add_text(text, extractor=None, scopes=None, causal_extractor=None, causal=None, dedup_threshold=None, resolve_conflicts=None)	Add text with entity + causal extraction; causal=False disables, True forces (raises if unavailable); dedup_threshold drops near-duplicates (unioning scopes); resolve_conflicts soft-supersedes contradicted facts when a conflict_resolver is set
add_texts(texts, extractor=None, causal_extractor=None, scopes=None, causal=None, dedup_threshold=None, resolve_conflicts=None)	Batch form of add_text (causal on by default)

Retrieve

Method	Description
query(query, top_k=5, hops=4, rerank_top_k=4, search_mode="embedding", rrf_k=60, recency_weight=0.0, scopes=None, isolate=None, include_superseded=False, as_of=None)	Search and traverse the graph. recency_weight in [0,1] blends recency into ranking; scopes narrows the seeds (traversal still crosses scopes unless isolate=True); as_of=<datetime> time-travels to what was current then; include_superseded=True keeps retired facts
query_detailed(...)	Same signature as query, but returns {content, score, created_at, scopes} per hit for thresholding/dedup
discover(query, top_k=5, hops=4, search_mode="embedding", rrf_k=60, scopes=None, max_results=10, max_visited=1000, isolate=None, include_superseded=False)	Like query, but returns connection paths -- how each fact links back to a seed via bridging entities, tagged with scopes, flagging cross-session links, and listing each fact's directed causes relations. The walk stops after max_visited nodes
answer(query, use_discover=True, top_k=5, hops=4, search_mode="embedding", scopes=None, max_results=10)	Rephrase the retrieved facts/paths into logical free text via the pluggable synthesizer

Causal reasoning

Method	Description
trace_effects(content, max_depth=6, scopes=None, isolate=None, include_superseded=False, max_visited=1000)	Forward causal walk: {origin, chain, terminals} for downstream impact
trace_causes(content, ...)	Backward causal walk: what led to content
root_causes(content, ...)	The root cause spans behind content (backward-walk terminals)
causal_chain(from_content, to_content, max_depth=6, scopes=None, isolate=None, include_superseded=False)	Ordered causal hops linking two facts, or None
what_if(content, origin=None, direction="effects", max_depth=6, scopes=None, isolate=None, include_superseded=False, max_visited=1000)	Counterfactual: prune a fact and report collapsed vs survived downstream spans

Update, forget, temporal

Method	Description
delete(content, purge_orphans=False)	Remove a node and its incident edges by exact content; purge_orphans=True also removes entities left dangling
supersede(old_content, new_text, extractor=None, purge_orphans=False)	Replace a stale fact: add new_text, then delete old_content
supersession_history(content)	Audit {supersedes, superseded_by} for a fact
delete_stale()	Remove nodes not accessed within forget_after days
maybe_forget()	Throttled delete_stale(): sweeps at most once per forget_every seconds (no-op when forget_every is None)

Datasets and inspection

Method	Description
load_dataset(name)	Load a built-in dataset
get_all_nodes(scopes=None) / get_all_edges()	Inspect graph contents (nodes optionally filtered by scope)

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

Variable	Default	Purpose
REASONGRAPH_BACKEND	memory	memory | sqlite | postgres
REASONGRAPH_DATABASE_URL	--	Postgres URL, sqlite path, or memory JSON path
REASONGRAPH_EMBED_MODEL	built-in	Model name; prefix fastembed: for pure-ONNX
REASONGRAPH_SYNTHESIZER	template	none | template | transformers
REASONGRAPH_SYNTH_MODEL	built-in	Instruct model for the transformers synthesizer
REASONGRAPH_FORGET_AFTER / REASONGRAPH_FORGET_EVERY	30 / off	Auto-forget window (days) and sweep interval (seconds). When the interval is set the service runs the sweep on a background task.
REASONGRAPH_ISOLATE	off	Confine traversal to the query session (multi-tenant). Off keeps cross-session discovery.
REASONGRAPH_RESOLVE_CONFLICTS	off	Enable contradiction resolution (soft-supersede) with the default NLI resolver.
REASONGRAPH_API_KEY	--	When set, data endpoints require it (Authorization: Bearer or X-API-Key); /health and /ready stay open.
REASONGRAPH_DEFER_EXTRACT	off	Run entity/causal extraction in a background worker (off the event loop) so pushes return immediately.
REASONGRAPH_SPAN_LINK_THRESHOLD	off	Cosine threshold (e.g. 0.85) above which a new cause/effect span is tied (same_as) to an existing causal span, so trace_* / causal_chain cross facts that phrase the same event differently.
REASONGRAPH_CAUSAL_MODEL	berk/causal-span-pointer-mdeberta	HF repo id or local dir of the span-pointer model.
REASONGRAPH_CAUSAL_GATE_THRESHOLD	0.5	Built-in gate: P(non-causal) above which the pointer abstains; 1.0 turns it off.
REASONGRAPH_CAUSAL_EMBED_GATE	off	Path or hf://owner/repo/file.joblib of an embedding-gate classifier; texts under REASONGRAPH_CAUSAL_EMBED_GATE_THRESHOLD (default 0.9) get no relations.
REASONGRAPH_DEDUP_THRESHOLD	off	Cosine threshold (e.g. 0.95) above which a pushed fact is treated as a paraphrase of an existing one: scopes are unioned, nothing new is stored.
REASONGRAPH_HOST / REASONGRAPH_PORT	0.0.0.0 / 8000	Bind address and port for reasongraph-serve.

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