cnx_vinyl/docs/plant-assistant.md

Plant Assistant: Ask the Plant

Decided (Alexander, 26 October 2026): the plant gets an agent that management and operators can ask, which reads the plant's knowledge base and its data and gives insight into the process. This document plans it on the systems of the digital factory: ERPNext as the system of record, the machine-data store, the factory application and the NixOS fleet. It is a planning position; every figure without a source is an estimate.

In one paragraph

One assistant for the whole plant, asked in Thai or English at a press kiosk, at a desk or on a phone. It answers from two places: the knowledge base (procedures, vendor manuals, safety rules, this planning repository) and the records and data (ERPNext documents, press cycles, inspection results, time series, alarms). Every answer names its sources; every number comes from a query it shows. It sees only what the person asking may see, it can draft but never submit a record, and it never touches a machine. It runs on site on an open-weights model, so it works when the internet does not.

Who asks what

Who	Typical questions	What it uses	Where
Press operator	"What is the band for the mould temperature at 180 g on the Classic?" "Non-fill rejects since 14:00, what changed?" "Show me the stamper change steps for the HRP 12." "Is compound lot L-0412 released?"	Quality Procedures (the SOPs), the recipe and inspection templates, the press's cycle rows and zone environment, the lot's Quality Inspection	press kiosk, Thai first, the station and job card already known
Shift lead	"Handover: what happened on the last shift?" "Which stampers are near retirement?" "Downtime by reason this week."	job cards, downtime entries, stamper serial numbers and play counts, open holds, alarms	kiosk, office
QC engineer	"Trace the record with this sleeve code." "Compare today's run of this title with the last repress." "Audio score against play count for stamper S-1187."	the record key's chain (cycle, stamper, mother, lot, environment) per traceability, inspection results, audio scores	office
Maintenance	"Alarm history of boiler B-1 this month." "Hours since the last oil change on the Duplex hydraulics?" "Page of the manual for the chiller's low-pressure fault." "Is the seal kit in stock?"	alarm history, run hours, ERPNext Asset Maintenance and stock, the vendor manuals attached to the Asset	workshop kiosk, phone
Cutting and galvanics	"Current density in cell 2 over the last father." "Which mothers of POY013 have sets left?"	rectifier and bath series, metal-part serial numbers	room kiosks
Management	"Yield and effectiveness per press this week, and why the Classic dropped." "Energy per record against the plan." "Orders at risk of missing their date." "Which gates are waiting on customers?"	ERPNext reports, the machine-data store, the design figures in this repository	office, phone
Customer service	"Where is order SO-0231, and when will it ship?"	the same records the customer portal shows	office
New staff and trainees	"Why must labels be dried before pressing?"	procedures and the training material, never live customer data	training mode

What it knows

The knowledge base: what should happen, and why

Source	Where it lives	Notes
Procedures and work instructions (SOPs), safety procedures, emergency steps	ERPNext Quality Procedure documents: structured, nested steps, versioned; a Non Conformance links to the procedure it breaks and a Quality Action carries the fix (ERPNext docs)	the SOPs are written into ERPNext during commissioning, not kept as loose files
Vendor manuals, datasheets, site requirements	attached to the ERPNext Asset (each press, boiler, chiller, lathe, cell) and Item	the vendor PDFs already filed under docs/equipment/ are the first ones
Recipes and limits	Item, BOM and Quality Inspection Templates (parameters and limits from quality automation)
Why the plant is built as it is	this planning repository, indexed from git	utility sizing, the metal archive, the QC layers, the decisions and their dates
Lessons learned	Non Conformance and Quality Review records with their actions
Thai and English terms	a glossary document (stamper, mother, non-fill, flash, run-out)	keeps the Thai answers consistent

Only approved, current versions are indexed. Superseded versions stay available for "what did the procedure say on 3 March?", marked as superseded.

Tacit knowledge is the part worth catching. P-Vine's pressing staff describe a room that changes every day with the weather despite air conditioning, so the settings (boiler temperature, a few seconds more or less of press time) are adjusted daily by feel (ele-king, VGAP interview; BRUTUS). Here every adjustment is a logged event next to the zone environment, so the assistant can answer "last time the press hall was this humid, what did the operator change, and did the rejects fall?" from the data, and a question nobody could answer goes to the shift lead as an ERPNext ToDo; the expert's answer, once approved, becomes a procedure note. The knowledge base grows from the floor's own questions.

The records and data: what did happen

• ERPNext: work orders, job cards, batches, quality inspections, metal-part serial numbers and their genealogy, downtime entries, stock, sales orders, gates, deliveries, assets and maintenance (who owns what).
• Machine-data store: press cycles, per-record optical results, audio scores, packaging scans and the hash-chained event log in PostgreSQL; 1 Hz machine tags, zone environment, energy and water in VictoriaMetrics (design decision 2).
• Alarms: vmalert and Alertmanager history.
• Catalogue data, for those who may see it (own catalogue).

What it does with it

1. Answers with sources: the procedure step and its version, the ERPNext document names, the query and time window behind a number.
2. Explains a number: yield down this week is broken down by press, title, stamper, compound lot, shift and zone environment. What moves together is reported as a correlation, never as the cause.
3. Traces: from a sleeve code or a complaint back through cycle, stamper, mother, lot and environment, in one answer.
4. Summarises: a handover note at each shift start (open holds, stampers near the end of their life, lots on hold, excursions, downtime), a daily plant note and a weekly management note.
5. Adds context to alerts: when vmalert fires, the alert still goes out through Alertmanager unchanged; the assistant follows it with what changed in the half hour before (lot start, stamper change, humidity, a neighbouring alarm).
6. Compares against the plan: actual cycle times, steam and energy per record, reject rates and repress lead times against the figures in this repository (scale, production timeline), so the plan learns from the plant.
7. Drafts records: a Non Conformance, a maintenance request, a ToDo, a revision of a Quality Procedure. A person reviews and submits.

What it never does

• Touches a machine. No writes to a PLC, an instrument, a recipe or a setpoint; the data platform is read-only toward machines (design decision 4).
• Submits a record. Drafts only; the person asking submits.
• Improvises on safety. For lockout, steam and boilers, hydraulics, galvanics chemistry, the crane and electrical work it quotes the approved procedure word for word with its version and names the responsible person. With no approved procedure it says so and stops. It is not an alarm and not an emergency channel (worker safety).
• Sees more than the asker. Every tool call runs with the asker's ERPNext role: an operator sees the job, not the customer's price; customer service sees orders, not payroll. The client audio vault and customers' artwork are never indexed. Questions that must be refused are part of the test set below.
• Answers from memory. A figure without a query or a document behind it is not given; missing data is said to be missing.
• Rates people. Operators' questions are logged to improve the answers and the procedures, not to assess the operator; that goes into the staff policy, and the logs are kept for a limited time (staff are data subjects under the PDPA).
• Needs the internet. Model, index and tools all run on site (design decision 8).

How it is built

• Model. Open weights, Thai and English, served on site. The first candidate is Typhoon 2.5 from SCB 10X, a Thai fine-tune of Qwen3-30B-A3B for Thai and English with a 256K context, Apache-2.0 (model card, checked October 2026), with a 4B sibling for quick kiosk answers. It is a mixture-of-experts model with about 3B parameters active per token, so it may run usefully on a CPU server before any GPU is bought (to be measured). The choice is made on our own test set, not on published benchmarks.

• Serving. llama.cpp or vLLM as a NixOS service on the clan, like every other plant service.

• Speech, optional. Typhoon ASR Real-time: open-source streaming Thai speech recognition that runs on CPUs, Apache-2.0 (model, code). Its authors name background noise and Thai-English code-switching as weaknesses, both of which the press hall has, so push-to-talk with a headset and a test on the floor come before any promise.

• Retrieval. Document chunks with embeddings in PostgreSQL with pgvector on vinyl-core, rebuilt from the sources (Quality Procedures and attachments in ERPNext, the repository). Derived and rebuildable; no business records.

• Tools. Exposed to the model over the Model Context Protocol, each a thin wrapper in cnx-factory:

  • ERPNext through the existing integration client, read as the asker, create drafts only;
  • SQL on the machine-data store through the PostgreSQL streaming replica on vinyl-backup, read-only with row and time limits, so a heavy question never slows the floor;
  • PromQL on VictoriaMetrics' read API;
  • document search, the event log and alarm history.

  An open-source MCP app for ERPNext exists (Frappe Assistant Core, AGPL-3.0); it runs inside Frappe as a second way into ERPNext, which the rule of one integration layer (how every tool interacts) does not allow, so its ideas are reused and the tools stay in cnx-factory.

• Front ends. An "Ask" panel in the factory application: on the station kiosks with the station, job card and the operator's language filled in, on office desktops, and on phones over the mesh. Same badge and sign-on identity as everything else.

• Machine. vinyl-ai in the IT room: one server with a 32 GB GPU. An RTX 5090 32 GB sells in Thailand for about 203,000 to 209,000 THB (Advice; JIB via BigGo; October 2026), so the server is roughly 250,000 to 300,000 THB (~7,500 to 9,000 USD, estimate). The cheaper start is CPU-only on the dev trio and then on vinyl-core, with the GPU bought only if answers are too slow for the kiosks.

Keeping it right

• A test set per role, in Thai and English: questions with known answers from the procedures and from recorded history, plus questions it must refuse (another customer's order, payroll, a safety step with no approved procedure). It runs on every change of model, index or tool, and nothing is deployed that fails it, the same rule as an ERPNext upgrade.
• Feedback on every answer; wrong answers are reviewed weekly by the QC lead, and the fix goes into the source (the procedure, the glossary, the data), not into a prompt.
• Measures: share of answers with a source, share of questions it could not answer, time to answer, use per role, incidents where it was wrong.
• Owners: the automation and IT engineer the digital factory plan adds to the headcount runs it; the QC lead owns the content.

Phasing

Roadmap phase	Step
0 to 1, now	Prototype on the dev trio over this planning repository: the team asks the plan ("how much steam does the launch plant need, and why?") in Thai and English, CPU-only; the test-set habit starts here
3, build	SOPs written as Quality Procedures during commissioning (vendor training sessions recorded and transcribed into procedures), manuals attached to the Assets; assistant v1 on documents and ERPNext records; vinyl-ai installed if the CPU trial says so
4, launch	"Ask" on the kiosks with station context; machine-data and alarm tools; shift handover notes; alert context
5, expand	Voice at the presses if the floor test passes; the catalogue advisor as one of its roles; galvanics and audio QC data; offered with the open plant stack to other plants (digital factory)

Rough cost (estimates)

Item	Estimate
vinyl-ai server with one 32 GB GPU	250,000 to 300,000 THB (~7,500 to 9,000 USD); none while CPU-only
Tools, retrieval and the "Ask" panel in cnx-factory	2 to 3 person-months
Test set and evaluation harness	0.5 person-month, then part of the IT role
Speech at the kiosks	0.5 person-month plus headsets
Writing the SOPs into ERPNext	part of commissioning and training, not IT time

Not in the digital factory hardware total or in the total investment.

Risks

• A confident wrong answer. Sources on every answer, no source no answer, and the safety quoting rule carry most of it; the test set catches the rest before a release.
• Stale procedures. Only approved versions are indexed, and every answer shows the version and date.
• Training replaced by asking. It supports training; training and sign-off stay with the supervisors and the safety programme.
• Noise and gloves. Voice is optional and tested on the floor first; the touch panel always works.
• Leaks across customers. Permissions per asker, refusals in the test set, and no customer audio or artwork in the index.

Open decisions

1. Model: Typhoon 2.5 or another open model, chosen on the test set.
2. Hardware: CPU first and a GPU only if needed (recommended), or vinyl-ai from the build.
3. Voice at the presses, after a floor test.
4. Web search for management questions through a fleet-hosted search, or none: the assistant stays on plant data and the repository.
5. Log retention for questions and answers.
6. Name on the kiosks.