How BooleX works
The principles, the sources BooleX cites and the parts of an answer.
Three rules that never change
- Read-only. BooleX only reads from PLCs, OPC UA servers, Modbus devices, historians, CMMS and document shares. No code path can write to them; every connector has a test that proves it.
- Advisory. BooleX tells you what it found and what to check. It never carries out a control action and never advises bypassing, defeating or resetting protection. A person decides.
- Cited. Every statement in an answer carries the source it rests on. A statement without a source is not shown. When nothing supports an answer, BooleX says so instead of guessing, and you can log the question as a knowledge gap.
Text read from documents and work orders is treated as data, never as instructions.
Sources and citations
Every citation is a source ID. Click one in an answer to open it in the source viewer.
| Scheme | Points to | Example |
|---|---|---|
plc:// | A rung, block, tag, alarm or interlock in the imported code | plc://bench/cip-bachmann/PRG_Interlocks/lines-29-33 |
doc:// | A document revision, page and section, or a spreadsheet row | doc://bench/OM-CIP-01@B/p14#4.2 |
wo:// | A work order or a technician journal record | wo://bench/WO-2025-0412 |
ts:// | A tag over a time window | ts://bench/TT101?from=…&to=… |
alm:// | One alarm occurrence | alm://bench/A017@2026-11-03T02:15:07Z |
dx:// | A confirmed diagnosis and its fix | dx://bench/DX-2026-0007 |
part:// | A spare part and its stock reading | part://bench/SEAL-P104-01 |
mdl:// | A behavioural model replayed on recorded data | mdl://bench/centrifugal-pump@2/P-101?variant=…&from=…&to=… |
The first part after the scheme is the site name from site.yaml. An answer records the content hash of each source it cites. If the source changes later, the viewer shows the cited revision and marks the citation as changed.
The parts of a diagnosis
- Evidence card. Shown within 2 seconds of opening a stop, before any language model is asked: the sequence of events, the first signs, the interlock that tripped, its cause chain in the code, the last confirmed fix and live values. It needs no model and works when the model is busy or offline.
- Sequence of events. The timeline rebuilt from alarm events and tag changes, with the candidate initiating event marked and up to two more ranked behind it. See Sequence of events.
- Candidate causes. Up to three, ranked. Each has its own cited statements, the values at the stop and now, and an evidence label that says which kinds of source support it.
- Checks. For each candidate, a check a person can carry out, with what would confirm it and what would rule it out. Report the result and the candidates are re-ranked.
- Labels. "AI-generated advice · read-only" on every answer; "Data quality" when a value was bad or missing; "Safety function involved" when the cause chain passes a safety program, with the site's safety procedure cited; "Drawing sets disagree" when two drawing sets wire a signal differently.
Draft causes stream in while the answer is written, so the first candidate shows early; the full answer replaces the drafts once every statement is checked.
Behavioural models and predictions
For equipment with a validated model (pumps, valves, tanks, heaters, and the sector equipment of the demo plants), BooleX can replay the model on the recorded inputs and compare it with what was measured. See Behavioural models. Predictions are always labelled "Model prediction", drawn dashed with their uncertainty band, and cited as mdl://. A model is used only after it passed validation against healthy runs of your plant.
Early warnings and workflows
- Early warnings flag a key tag that drifts outside the band of its good runs, or a start that runs longer than usual, before anything trips.
- Workflows run on plant events (an alarm, a stop, a work order, the end of a shift) and post a cited briefing to the inbox for a person to review.
Roles
BooleX has four roles: viewer, technician, expert and administrator. See Roles for what each can do.