ISA 5.1 · P&ID / MFD

The instrument index is already in the drawings.

EngAgents reads your revision-controlled P&ID and MFD set and drafts the full 16-column instrument index — every tag decoded against ISA 5.1, linked back to the page it came from, flagged where it is unsure. Your engineer reviews and approves instead of transcribing for a week.

Self-service signup · isolated workspace · TOTP required · drawings encrypted in your browser before upload

PID-2100-REV-C.pdf · unit 2100 · page 3 of 8reading
PT2101FIC2104LSHH2108TILE 2 / 5 · 300 DPI
instrument-index.xlsx18 tags
TagLocIOPg
PT-2101FieldAI3
FIC-2104DCSAO3
LSHH-2108ESDDI4
TT-21?2FieldAI4
1 tag needs a human read before approval
ISA 5.1
balloon shape → Field / DCS / ESD
16 columns
the standard index sheet, not our own
300 DPI
overlapping tiles keep small tags legible
AES-256-GCM
encrypted in the browser, before upload
The problem

A week of transcription, standing between you and the package.

The takeoff eats the schedule

Someone opens the drawing set and starts typing tags into a spreadsheet, one balloon at a time, for days. It is the least interesting work an instrumentation engineer will do all year, and it sits on the critical path.

Rev C makes you do it again

The set changes and the index drifts. Nobody can say with confidence which tags moved, which are new, and which quietly disappeared between revisions.

Procurement waits on it

Datasheets, RFQs, bid evaluations and IO counts all hang off the index. Every day it is not finished is a day the package downstream cannot start.

How it works

Four steps from a sealed PDF to an index you can defend.

No plugin, no template to fill in, no drawing conversion. Upload the set you already issued.

01

Upload the drawing set

A PDF up to 100 MB and 20 pages, A0 or smaller. Your browser encrypts it with AES-256-GCM before a single byte leaves the machine. The ciphertext lands in private object storage that has no public URL.

Encrypted in the browser
02

Render and tile at 300 DPI

Each page is rasterised at 300 DPI and cut into overlapping tiles, because a downscaled A1 sheet loses the 2 mm tag text that the whole index depends on. Dense A0 sheets get a finer cut.

No lost tag text
03

Read against ISA 5.1

Every tile is read with the ISA 5.1 identification standard in context: balloon shape decides Field / DCS / ESD, the letter string decodes to an instrument type, and line and equipment numbers are carried across from the drawing.

Decoded, not guessed
04

Merge, review, approve

Sightings of one tag across overlapping tiles are deduplicated — highest confidence wins, missing fields backfilled. You get a review table with the page each tag came from, then a draft XLSX, then an approved XLSX once an engineer signs off.

Engineer holds the pen
The output

The instrument index sheet your project already uses.

Sixteen columns, in the order your discipline expects, written straight to XLSX. Low-confidence rows are highlighted amber and flagged for manual verification rather than quietly shipped.

  • Page evidence on every row. Each tag records the page it was seen on, so a reviewer can go straight to the sheet instead of hunting.
  • Deduplicated across tiles. One tag seen in four overlapping tiles is one row — highest confidence wins, missing fields backfilled from the rest.
  • Draft and approved exports are separate files. You can circulate a draft without anyone mistaking it for signed work.
  • Manufacturer and Model come back as TBA. They are not on a P&ID, so they are not invented.
Column layout
01Unit No.02Loop Name03New Tag Numbers04Flange05Size06Instrument Type Description07Service08MFD Number09Line / Equipment Number10Indicator Location11IO Type Name12FSC/ESD Cabinet13Manufacturer Name14Model Name15Remark16REV

Instrument type descriptions are decoded from the ISA 5.1 letter string. Indicator location follows the balloon symbol — solid line for field, single line for a DCS-accessible shared display, ESD symbols kept distinct so safety instrumented functions do not get lost in the count.

Accountability

It drafts. A responsible engineer approves. That order is enforced.

EngAgents does not produce certified deliverables and does not pretend to. A job moves to approved only when a named, verified engineer approves it, and approval is blocked while required items are unresolved. Until then the export is labelled a draft for engineering review.

queued
Drawing set encrypted and registered
extracting
Page 3 of 8 · tile 2 of 5
review_ready
18 tags · 1 flagged for manual read
approved
Awaiting responsible engineer
Every state change is written to a client-scoped audit record.
Security & tenancy

Client drawings are the most sensitive thing you will ever email. Stop emailing them.

Isolation is not a setting in EngAgents. It is the shape of the schema, the storage, and the session.

Encrypted before it leaves the browser

Web Crypto AES-256-GCM with a one-object data key. The browser never receives the deployment master key or a tenant root key.

No public bucket, ever

Object storage holds ciphertext only, with no public URL and exact-origin uploads. Downloads are one-minute, one-use capabilities — never a storage URL.

Tenancy enforced in the database

Every query carries a client ID. Composite foreign keys and Postgres triggers reject cross-workspace ownership and tenant reassignment outright.

Row-level security as a second floor

Postgres RLS policies and a transaction-scoped tenant identity are implemented and tested underneath the application checks.

Verified email and TOTP, not optional

Self-hosted Better Auth handles accounts, sessions, organisations and TOTP. A Client Admin session is rejected without both controls.

Retention you set, deletion you can verify

Choose 0–30 days of retention at signup. Deletion revokes identity immediately and reports pending until two separate passes confirm the objects are gone.

The agent set

The index is the first agent, not the last.

Each agent takes the documents a discipline already produces and returns the artefact it already owes. Only the Index Agent is available today; the rest are planned and named here so you can see where the reviewed record goes next.

Available

Index Agent

P&ID / MFD drawing set → ISA 5.1 instrument index (XLSX).

Planned

RFQ Agent

Client spec plus datasheet template → a ready RFQ package.

Planned

TBE Agent

Vendor quotes against spec → technical bid evaluation matrix.

Planned

Inspection Agent

Field inspection workflows on the same reviewed record.

Questions

Straight answers.

What can I upload?+

One revision-controlled PDF drawing set per job: up to 100 MB, up to 20 pages, page size up to A0. Password-protected and structurally invalid PDFs are rejected at finalisation rather than half-processed.

What happens when the scan is poor?+

Uncertain tag characters are marked with a question mark and low confidence instead of being guessed. Those rows surface amber in the review table and in the workbook, so a bad scan costs you a check, not a wrong tag in procurement.

Why are Manufacturer and Model blank?+

They are returned as TBA. That information is not on a P&ID by nature — inventing it would be the one thing an instrument index must never do.

Does this replace the responsible engineer?+

No, and it is built so it cannot. Output is a draft for engineering review. Nothing is authorised for client use until a responsible engineer approves the job, and approval is blocked while required items are unresolved.

Who can see my drawings?+

One workspace maps immutably to one organisation, and a user belongs to one workspace. No authenticated request is allowed to name another workspace — the server derives it from your membership. Support access to a job is a separate, expiring, revocable, audited grant.

Where is the data stored?+

Neon Postgres and Cloudflare R2. Neither region selection nor a location hint guarantees South African data residency, so EngAgents makes no South African residency claim. If residency is a contractual requirement for you, tell us before you upload real project data.

Bring one drawing set. See the index it gives you back.

Signup is self-service and takes one step: your workspace, your admin account, your retention period. Verify your email, enrol TOTP, upload a set, review the result.

PDF · up to 100 MB · up to 20 pages · A0 and smaller