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Research 0001 v0.0 · This is an old version. Read the latest. · 25 October 2026

Turning message streams into trustworthy world models

How people and machines turn chat, meetings and email into threads, topics, entities, events and commitments: the theory, the research, what shipped and what retreated, what is solved and what is still open, and a reference architecture for building it.

Extracting a "world model" from chat, meetings and email is half solved: the structural plumbing is industry standard, while the semantic layer people actually want stays open. Header-based threading, quoted-text deduplication, templated extraction from machine-generated email (Google reports 95-97% precision) and meeting transcripts with summaries are commodity. Human-to-human commitments are not. That means detecting who promised what to whom, by when, whether it was accepted and whether it was ever done. No peer-reviewed LLM-era benchmark measures commitment or action-item extraction from real email or meetings, and the best pre-LLM commitment classifiers lose much of their accuracy when moved from one company's mail to another's. The theory has been around for decades. Speech-act theory, Clark's grounding, Singh's social commitments, bi-temporal databases and truth maintenance together give a precise vocabulary for what to extract and how to store it. The engineering lesson that runs through the evidence is that a world model built from messages has to be a revisable, provenance-linked projection over an immutable log, not a set of facts. Every derived claim should point back to its source message, carry its confidence and extractor version, and be invalidated rather than deleted. A human should be able to contest it. Three further constraints shape any design. Ingested email is a proven attack channel (EchoLeak, CVSS 9.3). Published memory-benchmark numbers for the same product vary by 20 points or more depending on who ran them. And no regulator has yet said how GDPR erasure reaches derived graphs and summaries.

Scope and evidence note. This report synthesises eight research notes compiled in October 2026. Figures labelled "vendor-reported" were produced by a company about its own product (or, where stated, a competitor's). Items the notes could not verify are flagged or left out. Several 2026 arXiv preprints were seen only through search summaries; they are marked where cited.

Summary: main conclusions and limits

Limits of this research

Main conclusions

How the report is organised

Figure 1 is a map of the report: the four questions it answers in order, and the two concerns that cut across all of them. Figure 2 places the main papers, products and incidents on one timeline. Figure 3 takes eight everyday problems and sets how people cope next to how machines try, and where the machines are known to fail.

1THEORYWhat is worthextracting?Speech acts, uptakeGrounding (Clark)Social commitmentsSituation modelsWho knows what2PIPELINEHow do machinesextract it?ThreadingRequests, commitmentsMeeting action itemsTime and contractsKnowledge graphsEntity resolution3WORLD MODELHow to storeand revise it?Immutable message logClaims + provenanceBi-temporal graphCommitment statesHuman review4PRODUCTSWhat shipped,what retreated?CommodityTemplated extractionMeeting recapsSmart ReplyPaused or goneCortana commitmentsInbox, x.aiApple news summariesRisksprompt injection through email · memory poisoning · erasure of derived data · workplace lawEvidencecontested memory benchmarks · no commitment benchmark · solved, maturing and open mapAcross all four
Figure 1. Map of the report. Source: structure of this report.
Theory and human studiesResearch and benchmarksProducts and incidentsFoundations, 1962–19991962Theory and human studiesAustin: utterances are actions, not only content1980sProducts and incidentsThe Coordinator: users tag each message as a speech act1991Theory and human studiesClark & Brennan: grounding, the evidence of being understood1991Theory and human studiesWegner: transactive memory, a “who knows what” directory1993Theory and human studiesSuchman: speech-act categories as discipline and control1996Theory and human studiesWhittaker & Sidner: the inbox doubles as a to-do list1998Theory and human studiesZwaan & Radvansky: situation models indexed by time, space, entity, cause, intent1999Theory and human studiesSingh: social commitments, a debtor owes a creditorClassic NLP and first products, 2004–20212004Research and benchmarksCohen, Carvalho & Mitchell: email speech acts; commitment F1 0.11–0.472010Research and benchmarksLampert, Dale & Paris: email zoning lifts request accuracy 72.3% → 83.8%2013Products and incidentsGmail: rule-based extraction from bookings and receipts in production2016Products and incidentsSmart Reply: 10% of Inbox mobile replies2017Products and incidentsCortana: suggested reminders from promises in sent mail2019Research and benchmarksKummerfeld et al.: 77,563-message chat disentanglement corpus2019Research and benchmarksAzarbonyad, Sim & White: commitment AUC falls 0.86 → 0.67 across companies2019Products and incidentsInbox by Gmail shut down2020Products and incidentsGoogle: ML extraction reaches 95–97% precision2021Products and incidentsx.ai acquired by BizzaboLLM era, 2023–20262023Products and incidentsMicrosoft pauses the Briefing commitments email2023Research and benchmarksGreshake et al.: indirect prompt injection2025Products and incidentsApple pauses news notification summaries after false headlines2025Research and benchmarksZep vs Mem0: the same benchmark scored 66.0 and 75.12025Research and benchmarksGraphRAG-Bench: graphs win on reasoning, tie on lookups2025Products and incidentsEchoLeak: zero-click injection through one email (CVSS 9.3)2026Products and incidentsGmail AI Inbox: suggested to-dos, US English first2026Research and benchmarksEmailBench: best agent passes 33.5% of scenarios
Figure 2. Timeline of the field. Source: dates and figures as cited in the sections below.
ProblemHow people copeHow machines tryKnown failure modeKeeping promisesRely on memory and flags;promises live in sent mailDetect commitments in sentmail (Cortana, 2017)Accuracy drops on anothercompany's mail (AUC 0.86 →0.67); Briefing email paused2023Reading indirectrequestsInfer intent from politeness,hedges and contextSpeech-act classifiers; LLMextractionHedged and conditionalrequests split even humanannotators (kappa ~0.68)Knowing it wasacceptedGrounding: look for evidencethe other side understoodTreat each detected requestas a taskUptake is rarely writtendown, and no benchmarkmeasures itAnchoring timeRead “next Friday” againstwhen it was saidLLMs resolve dates from thetextDurations 13.5–16% correct,off-by-one-day errors; nobenchmark on messagetimestampsFinding thingsagainScroll and search; heavyfolder users do no betterThreading, search, automaticbundles (Inbox)Automatic sorting tookcontrol away from users;Inbox closed in 2019Knowing who knowswhatTransactive memory: ask theright personInfer roles and experts fromwho writes to whomHierarchy inferencevalidated on one company(Enron) onlySummarisingMeeting notes and recapemailsLLM recaps and notificationsummariesApple's summaries producedfalse headlines and werepaused; GPT-4 Turbo spottedhallucinations with only 72%accuracyLabelling theconversationLeave acts implicit; peopleresisted declaring them (TheCoordinator)Infer acts automaticallyFeels like surveillance:Suchman's critique, theProductivity Score backlash
Figure 3. How people cope, how machines try, and how they fail. Source: the sections of this report on human practice, machine pipelines and industry; every entry is cited there.

Speech acts and grounding define what is worth extracting

The oldest and still most useful idea is that a message is an action, not just content. Austin separated what an utterance says from what it does (asserting, promising, ordering). His felicity conditions add that a request or promise is fully constituted only through uptake: the addressee has to take it up, or the act "misfires" (SEP Speech Acts). Indirect speech acts ("could you maybe look at…") depend on inferring intention, and some theorists treat them as implicature rather than a fixed form (SEP). Grice's maxims explain why meaning so often exceeds the literal text (Stanford handout). For a builder, these two ideas set the problem's ceiling: surface patterns will miss polite, hedged and conditional requests, and a request is not a commitment until there is evidence it was accepted.

Winograd and Flores turned this into a product, The Coordinator. Users labelled each outgoing message with a conversation category, and the system tracked pending commitments and project status (TOIS 1988 index, secondary description). Its successor, ActionWorkflow, modelled work as loops of request, commit, perform, declare complete and accept (Information Society 1993). Lucy Suchman's critique is the founding warning for this whole field. She argued that building systems on speech-act categories brings "an agenda of discipline and control" over the people categorised, and that the real politics lie in who defines the categories (EUSSET abstract). Winograd replied that explicit structure, like accounting procedures, supplies uniformity where ambiguity cannot be settled face to face (Winograd 1994, search summary). A 2010 essay says the Coordinator's demand for accountable communication limited it to "fairly small and dedicated networks" (ACM Interactions, snippet only). No adoption figures survive. The durable lesson is to infer acts from natural messages instead of asking users to declare them, while keeping the inference contestable. Automation removes the labelling burden but keeps the surveillance concern.

Multi-agent systems research gave commitments a data model. Singh argued that mentalistic (belief and intention) semantics fail in open systems and defined social commitments, which are directed (a debtor owes a creditor), arise in a context and can be manipulated in standard ways (Singh IJCAI-99; Singh AAAI-08). Castelfranchi required explicit acceptance by the creditor; Singh considers that right only for some applications (Commitments in MAS). Yolum and Singh's commitment machines compile commitment-based protocols into finite-state machines and allow exceptional moves that fixed message sequences forbid (Singh group). Symboleo applies the same approach to legal contracts. It gives state machines for the lifetimes of contracts, obligations and powers, and handles subcontracting, assignment and novation (Symboleo RE'20). These are ready-made schemas, not just philosophy. Contract-law tests (offer, acceptance, consideration) were not sourced in the notes, so the line between a social promise and a legally binding obligation remains a gap for human or legal review.

Clark and Brennan's grounding model adds the epistemic side. Shared understanding is built step by step, each contribution needs evidence that it was understood "to a level sufficient for current purposes", and the medium changes how costly that evidence is (Clark & Brennan 1991). Email is asynchronous, so acknowledgement often never arrives. One message does not establish common ground. Discourse theories supply structure. Grosz and Sidner describe intentional and attentional structure, including a focus stack. RST and SDRT give rhetorical relations (Grosz-Sidner discussion; SDRT intro). Together they suggest that a new message usually attaches to a recent open topic, which is a useful prior when linking messages.

Humans keep the world model in memory, inbox position and other people

Empirical HCI work shows how people actually cope, and it argues against designs that need users to file things. Whittaker and Sidner found email doubling as a to-do list and archive, with filing failures causing messages to be "lost" (CHI '96). A ten-year follow-up across 600 mailboxes found inbox sizes roughly unchanged while archives grew about tenfold (Microsoft Research). A field study of 345 users and more than 85,000 refinding actions found heavy folder users were no more successful at refinding and were marginally slower. Search and threading helped, and scrolling was the most common behaviour (bespacific summary; abstract-level only). Bellotti's Taskmaster grouped email, links and attachments into "thrasks" (thread plus task). Users received it well, but it never became a full product (CHI 2003). Microsoft Research found that promises live in outgoing mail and that people "just rely on memory" or on flags to track them (MSR blog). An open-commitments ledger therefore replaces a fragile human function, and it is useful only if it can tell an open commitment from a discharged one.

Cognitive science suggests what dimensions a world model should track. Zwaan and Radvansky's event-indexing model says readers build situation models, not textbases, indexed by time, space, entity, causation and intentionality. Long-term memory is a network of event nodes linked by shared indexes (Zwaan & Radvansky 1998). Wegner's transactive memory shows groups spreading memory across members through a directory of "who knows what". Couples who divided memory work naturally did better than strangers, and imposed assignments hurt performance (Wegner, Erber & Raymond 1991). The Pirolli-Card sensemaking model separates a foraging loop from a schema-building loop (Wikipedia summary). Its implication is that a machine world model should behave like a set of hypotheses revised as evidence arrives, not like a ledger of settled facts.

Machine pipelines work stage by stage, with uneven maturity

Threading is deterministic when headers survive and hard when they do not

Email threads are best rebuilt from Message-ID, In-Reply-To and References headers, with content similarity as a fallback. Some clients strip those headers, and threading on subject alone merges unrelated conversations (mail-threading docs). Chat without reply structure needs disentanglement, which is framed as predicting reply-to links and then clustering. The reference benchmark is Kummerfeld et al.'s 77,563 annotated Ubuntu IRC messages. That work also found that about 80% of conversations in the widely used Ubuntu dialogue corpus were missing messages or contained extra ones (arXiv 1810.11118). Getting whole threads exactly right is still hard. On that test set, supervised models reach cluster F1 of 36.6-51.7. A 2026 workshop paper reports prompted GPT-4.1 at 47.5 and Gemini-2.5-pro at 61.3; it has not been independently replicated (CEUR Vol-4178). A separate LREC 2026 study found out-of-the-box GPT-4o "performs poorly", while a fine-tuned GPT-4o Mini reached 74.4 link F1 but only 45.3 cluster F1 (ACL Anthology 2026.lrec-1.229). Zero-shot ChatGPT and GPT-4 trailed supervised BERT on IRC speaker identification by 25.6 and 12.3 points (arXiv 2310.16301). The practical reading is to use platform-native thread IDs as primary keys for structure, and to treat any content-inferred thread as a revisable cluster. Threads are also not topics. A 2026 Slack case study, a preprint seen only via search, argues that one thread can cover several unrelated topics (arXiv 2605.19627). The notes found no benchmark for linking one topic across threads.

Email speech acts and commitments: mature methods, low ceilings, poor transfer

Classifying email by intent is a 20-year-old, small-data field. Cohen, Carvalho and Mitchell's verb-noun taxonomy (Request, Propose, Commit, Deliver × Meeting, Information) reached precision above 80% and recall above 50% for some classes (EMNLP 2004). In the full paper, Commitment F1 ranged only 0.11-0.47, and annotator kappa sat between 0.72 and 0.83 (PDF). Lampert, Dale and Paris showed that preprocessing matters more than the model. On Enron, a request classifier rose from 72.3% to 83.8% accuracy once email "zoning" separated quoted, forwarded and signature text (a 41%+ error reduction). Human agreement was only kappa 0.681, and conditional or indirect requests drove the disagreement (NAACL 2010). Microsoft's sentence-level commitment work reached F1 0.78-0.81 within one corpus. Moved from Avocado to Enron, F1 fell to 0.73 and AUC fell from 0.86 to 0.67; adversarial domain adaptation recovered part of the loss (Azarbonyad, Sim & White, WSDM 2019). Smart To-Do reported 86% precision and 84% recall for commitment sentences on Avocado, against an annotator kappa of 0.694 (arXiv 2005.06282). Three conclusions follow. Human agreement near kappa 0.7 caps achievable accuracy. Zoning is a prerequisite. Per-organisation evaluation is unavoidable. Two targeted searches found no peer-reviewed 2023-2026 benchmark for LLM commitment or request detection in email. The closest is EmailBench, a September 2026 preprint seen via search, in which the best of eight agent configurations passed 33.5% of 206 scenarios even though 99.7% of its tool calls succeeded (arXiv 2609.31906).

Meetings: summaries are measurable, action items barely are

Action-item detection has very little labelled data. AMI has no direct action-item labels. Its 381 items across 101 meetings are derived by linking dialogue acts to summary sentences, and ICSI's annotations are no longer public (Liu et al., ICASSP 2023). Purver and colleagues found flat labels performed poorly and replaced them with utterance roles: task description, timeframe, owner and agreement (SRI, MLMI 2006; SIGDIAL 2007). That scheme remains the closest annotated model of an informal commitment. LLM-era work concentrates on summary errors. On the QMSum Mistake set (200 LLM summaries, 9 error types), GPT-4 Turbo detected errors with about 89% average accuracy but only 72% for hallucination (arXiv 2407.11919). Structured pipelines (FRAME) cut hallucination and omission scores by 2 of 5 points (arXiv 2509.15901). One signal matters for owner extraction. In Meeting Delegate, phonetically corrupted names, used as a stand-in for ASR errors, cut GPT-4o's explicit-cue response rate from 94.3% to 68% (arXiv 2502.04376). That paper did not measure action items, so the effect on assignee extraction is inferred. The notes found no verified LLM action-item F1 on AMI or ICSI.

Dialogue IE, time and contracts: strong where the schema is tight

Where the schema is fixed, conversation-to-state is close to solved. Cleaning MultiWOZ's labels (version 2.4) raised every state-of-the-art tracker's score (arXiv 2104.00773). Correcting inconsistent tags added 7-10% joint goal accuracy, while unseen entities cut it by 29%, a sign of entity memorisation (Qian et al., SIGDIAL 2021). Open relation extraction from dialogue is harder. On DialogRE, BERT scored 61.2 F1 overall but 55.4 when relations had to be found early in a conversation (Papers with Code). LLMs are competitive there but weak on inverse relations (IJCAI 2024).

Time is a specific weak spot. In the synthetic Test of Time benchmark, frontier models scored about 90-93% on "when did X happen" lookups. On timelines they scored 24-36%, and on duration arithmetic 13.5-16%, with frequent off-by-one-day errors (ICLR 2025). The paper's text and table disagree on one GPT-4 number (20.33% vs 40.25%). Relative expressions are hard for every system (Frontiers). The notes found no benchmark for resolving "next Friday" against a message timestamp. The design inference is to let the LLM output the unresolved expression and to do the date arithmetic deterministically.

0%25%50%75%100%Look up when an event happenedLook up when an event happened: 90–93%90–93%Convert time zonesConvert time zones: 74–90%74–90%Multi-step date arithmeticMulti-step date arithmetic: 26.6–62.6%26.6–62.6%Count events in an intervalCount events in an interval: 29.7–61.4%29.7–61.4%Order events on a timelineOrder events on a timeline: 24–36.3%24–36.3%Compute a durationCompute a duration: 13.5–16%13.5–16%
Figure 4. LLM accuracy on time questions. Source: Test of Time, ICLR 2025. Each bar spans the scores of GPT-4, Gemini 1.5 Pro and Claude 3 Sonnet (2024 models); the lookup row is approximate.

Contract clause extraction from formal documents works at "junior legal assistant" level. ContractEval ran 19 LLMs on CUAD (510 contracts, 41 clause types). Open models over-answered "no related clause", and thinking mode lowered correctness (arXiv 2508.03080). The best configuration in another CUAD study reached recall 0.77 and precision 0.66 (arXiv 2505.12837). The notes found no benchmark for obligation extraction from informal dialogue. The nearest relative, CraigslistBargain, captures only the agreed price (arXiv 1808.09637).

Graph construction, entity resolution and memory systems

LLM knowledge-graph construction comes in two schools. Schema-based extraction is precise but scales poorly; schema-free extraction is flexible but inconsistent (survey arXiv 2510.20345). KGGen's author-run MINE benchmark scores fact capture at 66% for KGGen, 48% for GraphRAG and 30% for OpenIE, with backbone models ranging from 44% to 73%. The authors acknowledge that "over or under de-duplication" remains, and their test texts are encyclopedic articles, not conversations (arXiv 2502.09956). For person and organisation identity, classical Fellegi-Sunter matching is mature: Splink trains unsupervised and scales past 100M records (PyPI). Generative LLMs match or beat fine-tuned models with little training data and generalise better to unseen entities (Peeters et al., EDBT 2025). Senzing's "principle-based" resolution reasons about how attributes behave, for example shared values versus stable ones. These are vendor claims (Senzing). The notes found no measured duplicate or merge-error rate on conversational data.

Schema-firstDefine the types, then extract into themEXAMPLESPalantir Ontology · Gmail templated extraction ·MultiWOZ slots · Symboleo contractsSTRENGTHS+Precise, consistent types+Easy to query, check and audit+Proven at scale on templated mailWEAKNESSES−Misses whatever the schema does not name−New types need modelling work−Brittle on entities it has not seenRESULTS•Gmail ML extraction: 95–97% precision•Dialogue state: fixing labels adds 7–10% accuracy•Unseen entities cut that accuracy by 29%Schema-freeLet the model propose entities and relationsEXAMPLESOpenIE · KGGen · GraphRAG · LightRAGSTRENGTHS+No upfront modelling+Captures the long tail+Helps multi-hop and summary questionsWEAKNESSES−Inconsistent types and relations−Duplicate or wrongly merged entities−High token cost per queryRESULTS•Fact capture: KGGen 66%, GraphRAG 48%, OpenIE 30%(author-run)•Same method, different model: 44% to 73%•Reasoning 53.4 vs plain RAG 42.9; lookups tie•Up to ~100K prompt tokens per query (LightRAG)•Mem0 removed graph memory from its open-source SDKA hybrid · this report's synthesisA schema for the core (people, commitments, events, time); open extraction for the long tail,promoted into the schema once a type keeps recurring; every claim keeps its source.Open questions · no answers foundHow should a schema grow from open extractions? What are real duplicate and merge-error rates onconversations? Does a graph still win against million-token context? Who approves a new type?
Figure 5. Two schools of graph construction. Sources: survey arXiv 2510.20345, KGGen, GraphRAG-Bench, Qian et al., CIDR 2020, Mem0 docs. The hybrid is this report's synthesis.

Agent-memory products fall into three families. Graph-indexed RAG includes GraphRAG, LightRAG and HippoRAG 2. Conversational fact stores include Mem0, Zep/Graphiti and MIRIX. Agent-managed files include Letta and Anthropic's memory tool. Of the systems verified, only Graphiti has first-class bi-temporal edges that invalidate old facts rather than deleting them (Graphiti GitHub). Graphiti also needs strong structured-output models; smaller ones often fail the schema. Mem0 has since removed graph memory from its open-source SDK, keeping entity linking only as a retrieval signal (Mem0 migration docs). Graphs earn their cost on multi-hop and summary questions, not lookups. In GraphRAG-Bench, plain RAG scored 60.9 on fact retrieval against HippoRAG2's 60.1. On complex reasoning HippoRAG2 led 53.4 to 42.9, and on summarisation MS-GraphRAG led 64.4 to 51.3. Prompt tokens per query ranged from about 880 for vanilla RAG to 38,700 for MS-GraphRAG local search and 100,800 for LightRAG (arXiv 2506.05690). Long context is not a free alternative. NoLiMa found 11 of 13 models fell below half their short-context score at 32K tokens, with GPT-4o dropping from 99.3% to 69.7% (arXiv 2502.05167). Accuracy is also lowest for information in the middle of the context (arXiv 2307.03172). Those results come from 2024-25 models.

Accuracy by task (%)Plain RAGBest graph method050100Fact retrievalFact retrieval: Plain RAG 60.960.9Fact retrieval: HippoRAG2 60.160.1 HippoRAG2Complex reasoningComplex reasoning: Plain RAG 42.942.9Complex reasoning: HippoRAG2 53.453.4 HippoRAG2SummarisationSummarisation: Plain RAG 51.351.3Summarisation: MS-GraphRAG 64.464.4 MS-GraphRAGPrompt tokens per query050K100KPlain RAGPlain RAG: 879 tokens879MS-GraphRAG localMS-GraphRAG local: 38,707 tokens38,707LightRAGLightRAG: 100,832 tokens100,832
Figure 6. Graph RAG against plain RAG: accuracy and cost. Source: GraphRAG-Bench, arXiv 2506.05690, GPT-4o-mini on the novel-text dataset. The best graph method differs by task.

What shipped, what retreated, and how practitioners work

Industry history follows a clear rule: features that summarise or extract from templated mail became commodity, while features that need accountability (owner, due date, acceptance) retreated or remain unmeasured.

Google's Gmail extraction (Juicer) is the most rigorous production evidence and covers machine-generated mail. A rule-based extractor has run since 2013. Moving to ML raised event precision from 90.0 to 95.3 and purchase precision from 90.0 to 97.5. Templates were whitelisted only when a weekly random sample scored above 90% precision, fixing faulty legacy labels added 8-9 precision points, and more than 45,000 lines of rules were deleted (CIDR 2020). The system serves over a billion users without engineers seeing individual emails (Google Research). Senders can also supply structure themselves through schema.org markup (Google developers). Smart Reply shows that tightly constrained generation scales: it produced 10% of mobile replies in Inbox (KDD 2016). None of this is evidence for extracting human commitments.

Microsoft shipped commitment detection and then retreated. Cortana's 2017 "Suggested Reminders" spotted promises in sent mail (eWeek). The Briefing email listing outstanding commitments was paused on 15 January 2023, with no stated reason (Microsoft support). Cortana itself reached end of support, and its email feature Play My Emails was retired in June 2024 (Microsoft Support). Google Inbox closed in 2019 as part of product consolidation. Snooze, nudges and Smart Reply moved into Gmail, but bundles did not (Wikipedia). The assistant-as-participant model did not survive as a standalone business: x.ai was acquired by Bizzabo in June 2021 (CB Insights), and Clara Labs' acquisition dates conflict across sources. Apple's notification summaries falsely reported a news event in December 2024, so Apple paused news summaries in iOS 18.3. It restored them in the iOS 26 beta with the warning "Summarization may change the meaning of the original headlines" (AppleInsider). The fix was a UI disclaimer, not better accuracy. Gmail's January 2026 "AI Inbox" added suggested to-dos, starting with US English users (secondary sources only) (TechRepublic).

Meeting tools are commodity, and their accuracy is not measured. A university review of Zoom AI Companion found action items accurate "when explicitly stated" (Seattle U). An Otter pilot found them "sometimes incorrect" (Univ. of Alabama). A CSCW 2025 study of an LLM recap prototype with seven Microsoft employees found users adding, editing and deleting content, and noted hallucination risk on long dialogue (arXiv 2307.15793). No vendor publishes action-item precision or recall, and the notes found no independent product study. Vendor-reported impact numbers do exist. Microsoft's randomised Copilot trial (66 firms, 7,137 workers) reported that regular users cut email time by about 3.6 hours a week. The intent-to-treat effect was about 1.3 hours, and only about 40% of those offered access used it regularly (arXiv 2504.11436, vendor-authored).

Two older industries already solved parts of the problem. eDiscovery treats a thread as a graph with "inclusive" terminal messages that contain all earlier text, so reviewers read only the minimal set. Microsoft Purview flags both branches of a fork as inclusive, where Outlook's conversation view could hide unique mid-thread content (Purview docs; Relativity). Enterprise graphs take two approaches. Palantir's Ontology is schema-first: humans define objects, links and actions, and data is mapped in rather than learned from text (Palantir docs). Atlassian's Teamwork Graph builds from tool metadata and permissions, and opened through an MCP server in May 2026 (Nasdaq release). Contract-management vendors publish no comparable extraction benchmarks, and buyers are advised to run their own scored bake-off of about 200 contracts (Beri). The notes found no shipped product that tracks informal email and chat commitments across sources, apart from Microsoft's retreated features.

The solved, maturing and open map

Figure 7 names the problem domains of the field and marks each one; the table below gives the evidence for each mark.

24 named problem domains5 solved5 solved9 maturing9 maturing10 open10 openStructureEmail threadingSolvedZoning, inclusiveemailsSolvedTemplatedextractionSolvedChatdisentanglementMaturingActs andobligationsReply suggestionSolvedRequest detectionMaturingMeeting summariesMaturingIndirect, hedgedrequestsOpenCommitmentlifecycleOpenMeeting actionitems, decisionsOpenTime, events,contractsDialogue statetrackingMaturingDialoguerelationsMaturingFormal contractclausesMaturingRelative time,durationsOpenObligations ininformal talkOpenKnowledgeand memoryBi-temporal storage,provenanceSolvedLLM graphextractionMaturingEntityresolutionMaturingAgent memorystoresMaturingCross-threadtopic linkingOpenReasoning overmemoryOpenTrust andevaluationInjectionrobustnessOpenErasure ofderived dataOpenTrustworthybenchmarksOpen
Figure 7. The problem domains and their status. Source: the table below. A domain is "open" when no method or benchmark shows it working on real conversations.
Status Capability Evidence and caveat
Solved / industry standard Header-based email threading, inclusive-email detection, near-duplicate grouping Standard in Relativity and Purview (Purview); breaks when clients strip headers or servers insert footers
Solved Extraction from templated, machine-generated email (bills, bookings, purchases) 95-97% precision at Gmail scale (CIDR 2020); sender schema.org markup
Solved Transcription, meeting summaries, explicitly stated action items Commodity in Zoom, Teams, Otter, Granola; accuracy unpublished, explicit items reported fine (Seattle U)
Solved Constrained reply suggestion Smart Reply, 10% of Inbox mobile replies (KDD 2016)
Solved (engineering) Bi-temporal storage, event sourcing, provenance vocabularies, deterministic ER on strong keys, Fellegi-Sunter matching SQL:2011 temporal tables; Fowler; PROV-O; Splink
Solved (research) Email zoning as preprocessing +11.5 accuracy points on requests (Lampert 2010); zoners brittle across corpora
Maturing Chat disentanglement without reply metadata Cluster F1 roughly 45-61, single unreplicated LLM result at the top (CEUR)
Maturing LLM structured extraction into a graph; LLM entity matching KGGen 66% fact capture, author-run (arXiv 2502.09956); Peeters EDBT 2025
Maturing Agent memory stores (Mem0, Zep/Graphiti, Letta, MIRIX) Benchmarks contested, see the "conflicting numbers" section below
Maturing Graph RAG for multi-hop and corpus summaries Wins on reasoning and summary, ties on lookup, costs up to ~100× tokens (GraphRAG-Bench)
Maturing LLM thread and notification summaries Shipped everywhere; Apple's public failure; ROUGE does not track human judgment (EmailSum)
Maturing Contract clause extraction from formal documents "Junior legal assistant" level (ContractEval)
Maturing Schema-bound dialogue state tracking Close to solved on cleaned MultiWOZ; degrades on unseen entities (Qian 2021)
Open Commitment and request extraction from human email with lifecycle (accepted, delegated, discharged) No LLM-era benchmark; cross-corpus AUC 0.86→0.67 (WSDM 2019); Microsoft Briefing paused
Open Meeting action items and decisions with correct owner and deadline No verified LLM F1 on AMI or ICSI; labels derived, tiny (ICASSP 2023)
Open Indirect, conditional and hedged requests Main driver of annotator disagreement (Lampert 2010)
Open Relative-time resolution against message timestamp; timelines and durations No benchmark; durations 13.5-16% (Test of Time)
Open Cross-thread topic and story linking; new-topic detection No benchmark; TDT found first-story detection unreliable (Allan, UMass)
Open Reasoning over dependencies, absence and deletion in memory Cascade 3%, Absence 1% across six systems (MEME; independence unchecked)
Open Erasure propagated through derived facts, summaries, embeddings 2026 preprints only; no regulator guidance (arXiv 2602.17692)
Open Robustness to prompt injection from ingested messages Production CVEs, architectural defences only (arXiv 2509.10540)

The hard problems have one thing in common. They need pragmatic inference (intent, uptake, implicature), temporal reasoning anchored to context, or knowledge of what was not said. Much of the world never reaches the channel: calls, hallway decisions and documents. "Nobody wrote 'done'" therefore tells you nothing about whether a commitment was kept.

Figure 8 breaks the goal most people actually want, a ledger of who owes what, into the sub-problems it needs. Most of the tree is open.

19 sub-problems behind one goal3 solved3 solved4 maturing4 maturing12 open12 openGOALKnow who oweswhat to whom,by when, andwhether it wasdone1 Find theconversation2 Recognisethe act3 Fill in thecommitment4 Trackits life5 Keep the modelconsistent6 Make it safeand provableSolvedRebuild email threads from headersSolved · standard in eDiscovery toolsSolvedStrip quotes, signatures; inclusive emailsSolved · zoning adds 11.5 accuracy pointsMaturingUntangle chat without reply linksMaturing · cluster F1 roughly 45–61MaturingExplicit requests and promisesMaturing · F1 0.78–0.81 inside one corpusOpenIndirect, hedged, conditional requestsOpen · main source of annotator disagreementOpenWork on a new organisation's mailOpen · AUC 0.86 → 0.67 across companiesMaturingWhat: the task itselfMaturing · explicit items fine; no published F1OpenWho: the right ownerOpen · garbled names: response rate 94.3% → 68%OpenWhen: “next Friday” from the send timeOpen · no benchmark; durations 13.5–16%OpenWas it accepted?Open · uptake is rarely written; not measuredOpenDelegated, renegotiated or moved?Open · no system or benchmark foundOpenWas it done?Open · discharge is rarely written downSolvedStore history and provenanceSolved · bi-temporal tables, event sourcingMaturingSame person across addressesMaturing · solved on strong keys onlyOpenReason over dependencies and absenceOpen · 3% and 1% across six memory systemsOpenLink one topic across threadsOpen · no benchmarkOpenResist instructions hidden in emailOpen · EchoLeak, CVSS 9.3OpenErase derived facts on requestOpen · 2026 preprints onlyOpenProve accuracy on real mailOpen · no public commitment benchmark
Figure 8. The problem tree behind "who owes what". Source: synthesis of this report; each leaf's evidence is cited in the sections above.

A reference architecture: log, claims, beliefs, review

This section is synthesis. Each layer is grounded in the sources cited, but the composition and several mechanisms (marked "inference") go beyond what any single source tested. The central design choice, inferred from the knowledge-representation notes, is to keep three layers apart. The first is the immutable message. The second is the claim extracted from it, a statement about a statement with provenance and confidence. The third is the believed world state computed from claims. RDF 1.2 "triple terms" with reifiers are the standards-track way to say "A claimed P" without asserting P. RDF 1.2 was still a Candidate Recommendation as of 7 April 2026 (W3C RDF 1.2). Property graphs get the same effect by promoting each claim to a node.

SolvedMaturingOpen1Immutablemessage logSolvedSolvedevent sourcing2Normaliseand zoneSolvedSolvedquotes, signatures3Thread anddisentangleMaturingMaturingheaders solved4ExtractclaimsOpenOpencommitments open5ResolvetimeOpenOpenno benchmark6EntityresolutionMaturingMaturingstrong keys solved7Bi-temporalbelief graphMaturingMaturingparts solved8Commitmentstate machineOpenOpenlifecycle untested9Topics, stories,casesOpenOpenlinking threads10HumanreviewOpenOpenno study found
Figure 9. The reference pipeline, coloured by maturity. Source: synthesis of this report; the maturity colour is the status of the hardest part of each layer, from the solved, maturing and open table.
Layer What it does Grounding Status
1. Immutable message log Append-only store of raw messages, metadata, attachments and every extraction output (model id, prompt version, input hash) Fowler: state is a replay of events; external query results must be logged so replays are deterministic (Fowler); PROV-O Entity/Activity/Agent (W3C) Sourced pattern; treating LLM calls as "external queries" is inference
2. Normalise and zone Strip quotes, signatures and footers; detect inclusive messages; deduplicate Zoning +11.5 points (Lampert); inclusive sets (Relativity) Sourced
3. Thread and disentangle Native IDs first, header threading second, content disentanglement as a revisable cluster Kummerfeld 2019; CEUR 2026 Sourced; "thread is not a primary key" is inference
4. Extract claims LLM or classifier emits typed acts (request, commit, decision, fact, event) with span evidence, debtor/creditor, raw time expression and confidence Purver role scheme (SRI); Singh commitments (AAAI-08); SEM Event/Actor/Place/Time (SEM) Schema is inference from these
5. Resolve time deterministically Anchor relative expressions to message send time and time zone; represent fuzzy times as intervals OWL-Time intervals (W3C); LLM duration failures (ToT) Inference (no benchmark exists)
6. Entity resolution Auto-merge on strong keys (exact address), probabilistic plus review on weak keys (display names); merges stored as reversible sameAs assertions Splink; Senzing (vendor); Peeters Reversibility is inference
7. Bi-temporal belief graph Each fact has valid time and transaction time; supersession closes intervals instead of deleting; conflicts surface as flags; current belief is computed from justifications (TMS-style) so retracting a source retracts its consequences Snodgrass bitemporal (Wikipedia); Graphiti invalidation (GitHub); Doyle TMS vs AGM (Shapiro) Sourced components; combination is inference
8. Commitment state machine proposed → accepted/declined/unanswered → active → discharged (inferred vs confirmed) / cancelled / delegated; "violated" set by a clock-driven evaluator Commitment machines (Singh group); Symboleo; uptake (SEP) States are inference
9. Topics, stories, cases Thread (structural) → topic (semantic cluster) → story (TDT-style temporal cluster) → case or matter (human-curated, authoritative) BERTopic; TDT Layering is inference
10. Human review Confidence-gated queues; one-click confirm or dismiss; corrections logged as highest-authority events Suchman contestability (EUSSET); users edit recaps (CSCW 2025) Mostly inference; no HITL study on commitments found

Several engineering consequences follow from Fowler's event-sourcing rules. Replays must never re-send real outgoing messages (reminders, notifications), so the outbound gateway has to be disabled during rebuilds. Re-extraction with a better model should be an explicit new run rather than silent drift, with idempotency keyed on (message id, extractor version), which is an inference (Fowler). "We moved the meeting" is a supersession, not a contradiction: the new claim closes the old valid-time interval and both remain queryable "as known on date X". A real contradiction, where two sources disagree about the same time, should be flagged rather than silently overwritten. Store extraction confidence separately from source reliability rather than multiplying them into one number. The notes did not verify how well-calibrated LLM confidence is.

Evaluation has to be built in, because the literature cannot supply the numbers for your domain. The notes propose, as inference, measuring:

Google's practice of whitelisting an extractor only when a weekly random sample clears 90% precision is a proven operational gate worth copying (CIDR 2020).

Ingested messages are an attack surface and a liability

Every inbound email is untrusted input to a privileged system. Greshake et al. named indirect prompt injection in 2023: instructions embedded in retrieved content can steal data, spread like a worm and contaminate ecosystems (arXiv 2302.12173). EchoLeak (CVE-2025-32711, CVSS 9.3) made it zero-click against Microsoft 365 Copilot through one crafted email. It was fixed server-side in June 2025, and Microsoft reported no exploitation in the wild (The Hacker News). The exploit chain evaded the injection classifier with plain, human-sounding wording. It used reference-style Markdown to get past link redaction, auto-fetched images, and a Teams proxy the content security policy allowed. The proposed defences are architectural: prompt partitioning, provenance-based access control, strict CSP and least privilege (arXiv 2509.10540). Gemini's Gmail summaries could be made to show an attacker's fake security warning hidden in zero-size white text (0DIN). Slack AI had a prompt-injection path to private-channel data (The Register). A commitment tracker that reads inbound mail, holds privileged context and can remind or act has exactly the EchoLeak shape.

Memory poisoning makes injection persistent. SpAIware planted lasting instructions in ChatGPT's macOS memory for continuous exfiltration across future chats (The Hacker News). MINJA showed attackers can plant malicious memory records through ordinary queries, without write access, with over 95% injection success, and that those records affect other users' later queries (arXiv 2503.03704). AgentPoison reached over 80% average attack success with under 0.1% of the store poisoned, though it needs write access (arXiv 2407.12784). For a world model, a forged email saying "the deadline moved to never" is a belief-revision attack. Mitigations implied by the evidence include:

The last two are inference.

Erasure of derived data is unsolved. No regulator has said how GDPR Article 17 applies to derived knowledge graphs, summaries or embeddings. EDPB Opinion 28/2024 says a model is anonymous only if identification is insignificantly likely by "all means" (secondary summaries only) (CMS). A 2026 preprint models agent memory as a dependency graph from raw memories through summaries to KG entities, so deletion can cascade. It documents "backflow", where deleted facts resurface through derived artifacts (arXiv 2602.17692). The GONE benchmark measures multi-hop leakage after KG fact unlearning (arXiv 2603.12275). The architecture above makes deletion cascades possible only if every derived fact keeps a provenance edge back to its source messages. Bi-temporal "invalidate, never delete" conflicts with erasure, so a separate hard-delete path is needed. That last point is inference.

Workplace context adds legal and social limits. The EU AI Act bans inferring emotion from biometric data in workplaces; text-only sentiment is arguably outside the ban (FPF). In Germany, tools capable of monitoring behaviour trigger works-council co-determination (Reusch Law). Otter faces a consolidated class action, so far only allegations, over recording without all-party consent (NPR/Boise State). Microsoft's Productivity Score removed per-user names within weeks of launch after surveillance criticism (PCWorld). Suchman's 1993 critique describes the same backlash.

Things you probably have not thought of

A request is not a commitment, and silence is not acceptance. Speech-act uptake and Castelfranchi's acceptance condition mean every directive needs a state of proposed, accepted, declined or unanswered. Clark's grounding means "sounds good" may not cover everything in the thread. Discharge is rarely written down, so "done" should have inferred and confirmed variants, and the model needs an explicit "not observed" value for off-channel outcomes.

A who-knows-what index may be worth more than the fact graph. Transactive-memory research shows that groups retrieve by asking the right person (Wegner 1991). Authorship and reply patterns already reveal owners and experts per topic. Enron studies recover hierarchy from volume, response time and centrality, validated against a real org chart for one company only (CorpRank). Answering "ask whom" sidesteps many extraction-accuracy problems.

Inclusive emails eliminate most duplicate extraction. A reply quotes its whole history. Without eDiscovery-style inclusive detection, the same commitment is extracted once per reply and entity resolution has to clean it up later. Two related traps: mail servers insert footers that break body matching (Relativity), and date-filtered searches combined with threading can silently drop messages (Above the Law).

Benchmark numbers for the same product disagree by 20 points or more.

Full context, no memory system: 72.9LoCoMo ceiling if 6.4% of the key is wrong: ~93.60255075100ZepLoCoMoZep on LoCoMo: 65.99 (run by Mem0)run by Mem0 66.0Zep on LoCoMo: 75.14 (Zep's rerun)75.1 Zep's rerunMem0LoCoMoMem0 on LoCoMo: 66.88 (Mem0 paper, 2025)Mem0 paper, 2025 66.9Mem0 on LoCoMo: 92.5 (Mem0 page, 2026)92.5 Mem0 page, 2026Vertex Memory BankLongMemEvalVertex Memory Bank on LongMemEval: 42.4 (Redis rerun)Redis rerun 42.4Vertex Memory Bank on LongMemEval: 70 (as reported)~70 as reported
Figure 10. The same memory system, scored by different people. Sources: Zep and Mem0 (both vendors), Redis (vendor rerunning others), Penfield Labs audit (competitor). Mem0's two scores are its own, a year apart.

Trust only same-harness reruns on your own data.

More memory can make answers worse. Mem0 reports that its multi-session score fell from 93.2 to 88.0 as more memories were retrieved (vendor-reported) (Mem0). Graphiti's invalidate-only design has no forgetting mechanism: schedule details and identity traits are structurally identical edges (analysis). Salience and decay need their own design.

Your training and evaluation data is probably contaminated or unrepresentative. Enron is one company in 2001, widely included in pretraining, and full of cleaning artefacts. Avocado cannot be redistributed. Commitment models lose much of their accuracy between the two (Azarbonyad). Budget for in-domain annotation, and expect a human-agreement ceiling around kappa 0.7. Fixing your own labels can be worth more than changing models, as Google's 8-9 point gain from cleaning legacy labels shows.

ASR errors become ownership errors. Corrupting names cut a meeting agent's response rate from 94.3% to 68% (Meeting Delegate). Without speaker diarisation and name verification, action items get assigned to the wrong person; one anecdote reports an item assigned to someone who did not attend (Jamie blog).

Users stop checking. A CHI 2025 study, seen only as a snippet, found participants often accepting AI outputs as accurate without verifying them (ACM DL). Review queues decay into rubber stamps unless confidence and evidence are shown at the moment of decision.

Valid tool calls are not completed tasks. EmailBench's 99.7% successful tool calls against a 33.5% scenario pass rate is a warning against operational metrics that look healthy while the world model is wrong (arXiv 2609.31906, preprint).

The schema is political. Suchman's question of who defines the categories, and the Productivity Score backlash, both say: show people the commitments attributed to them, let them contest, and avoid per-person scoring by default.

No single discipline owns this problem, so the vocabulary changes at every boundary. The literature is split across NLP and dialogue (ACL, EMNLP, NAACL, SIGDIAL, LREC), information retrieval and data management (SIGIR, WSDM, KDD, CIDR, VLDB, EDBT), semantic web (ESWC, Journal of Web Semantics, W3C), multi-agent systems (IJCAI, AAMAS-family commitment work), requirements engineering (RE, SoSyM for Symboleo), and HCI and CSCW (CHI, CSCW, ECSCW). Useful search terms include:

Datasets What it gives you Caveat
Enron (Klimt & Yang) ~200K cleaned messages, 158 users Single 2001 company; counts vary by version; pretraining contamination
Avocado (via Azarbonyad) ~940K emails, 279 accounts LDC licence, not redistributable
BC3 (Ulrich 2008) 40 W3C threads with summaries and speech-act labels Mailing list, not private workplace
EmailSum (ACL 2021) 2,549 threads with short and long summaries ROUGE weakly tracks humans
Ubuntu IRC disentanglement (Kummerfeld 2019) 77,563 reply-linked chat messages Technical domain
AMI / ICSI (Liu 2023) Meetings; 381 derived action items on AMI ICSI action labels not public
QMSum Mistake, MeetingBank (arXiv 2407.11919; Zenodo) Summary-error labels; 1,366 council meetings Summaries, not action items
DialogRE, MultiWOZ 2.4 (DialogRE; MultiWOZ 2.4) Dialogue relations; task-oriented state Not workplace
CUAD, ContractNLI (CUAD; ContractNLI) Formal contract clauses and entailment Formal text only
LoCoMo, LongMemEval (LongMemEval) Long-memory QA Contested scoring; few update questions

Surveys worth reading:

The notes found no survey of conversational information extraction as a whole.

A suggested reading order for a builder moves from what to extract, to how to store it, to what has been measured:

  1. What to extract. SEP on speech acts, then Clark & Brennan, then Suchman's critique (EUSSET), then Singh on commitments.
  2. How it has been measured. Cohen 2004, Lampert 2010, Azarbonyad 2019 and Kummerfeld 2019.
  3. How to store it. Fowler on event sourcing, bitemporal modelling, PROV-O, RDF 1.2, then Zep/Graphiti, then the Doyle/AGM overview.
  4. What production taught. Google's CIDR 2020 Juicer paper, then the GraphRAG-Bench and EchoLeak analysis.

Conclusion

The field's centre of gravity has moved from classification to state maintenance. The 2004-2019 work showed that speech acts and commitments can be detected moderately well inside one corpus. Industry has shown that accurate extraction is only possible where the text is templated. What nobody has demonstrated publicly is the next step: keeping a correct, current, contestable ledger of who owes what across email, chat and meetings, including acceptance, delegation and discharge. That gap is an opportunity. It is also where Microsoft retreated and where the benchmarks are weakest. A credible entrant therefore competes less on extraction accuracy than on trustworthiness of state, meaning provenance on every claim, bi-temporal history, reversible merges, a clock that marks commitments violated, a deletion path that actually cascades, and a review loop people use.

Two strategic implications follow. Because no public benchmark measures commitment lifecycles, a builder's own labelled evaluation set is a moat and a necessity: per-tenant samples, Google-style weekly precision gates, and task-level questions such as "what do I owe X?". And because the same ingestion pipeline that builds the world model is the injection vector, security architecture cannot be bolted on later. Untrusted senders' claims should never silently overwrite trusted state, and nothing extracted from an inbound message should trigger an outbound action without a human in the loop.

About this report and its session log

How it was made. One Claude Code desktop session on 25 October 2026, with Claude Opus 5.5 as coordinator, produced everything here. It followed the deep-research pattern:

The coordinator then added the summary chapter, the figures and the infographics. The researchers' notes, with every source, are in notes/.

Session log. The full transcript of that session, including every researcher's own transcript, is kept in the RESEARCH repository at:

LOG/0001-world-models-from-conversations/14ea11bf-dd20-4531-8b79-2fedea455aaa.jsonl

with the subagent transcripts in the folder of the same name beside it. The session id is 14ea11bf-dd20-4531-8b79-2fedea455aaa. LOG/ is not on GitHub. A weekly job (tools/research_sessions.py in the repository) copies any newer version of the transcript into LOG/ and freezes LOG/ to cold storage under the label research-sessions.

To ask this session a question later, copy the .jsonl file into the Claude Code project folder of the directory you start Claude in, then resume it by id. For the RESEARCH repository that folder is ~/.claude/projects/-Users-annakubasiak-repos-RESEARCH/. Then run claude --resume 14ea11bf-dd20-4531-8b79-2fedea455aaa from the repository. The repository's LOG/README.md gives the same steps, and how to thaw the file from the freezer if the local copy is gone.