The Engagement: Larkfield at Harbourline Freight

Every lesson in this course is set inside one customer engagement. Both companies are made up. All people, numbers, documents and events in it are fictional and simulated. The real cases that open each lesson are separate, cited, and clearly marked as real.

The two companies

Larkfield Systems is your employer. It sells Larkfield Assist, a platform for building AI assistants over a company's own documents and systems. You are a forward deployed engineer (FDE) at Larkfield. Your job is to make the product work inside a customer's organisation, on their data, against their constraints.

Harbourline Freight is the customer. It is a regional freight carrier based in the north of England. It moves pallets and parcels for about 3,000 business customers and has around 600 staff. It works in pounds sterling, writes dates day first, and follows the bank holidays of England and Wales. Personal data it holds falls under UK data protection law, which gov.uk names as the UK GDPR and the Data Protection Act 2018 (gov.uk/data-protection, checked 9 October 2026). That is context for the story, not legal advice.

The problem

When a delivery goes wrong, it becomes an exception: late, damaged, missing, or sent to the wrong address. Harbourline handles about 1,400 exceptions a week.

• A claims team of nine works them from a shared spreadsheet, exceptions_master.xlsx, and a shared email inbox.
• Each exception means looking in three places: the transport management system (TMS), the customer relationship system (CRM), and the email thread.
• The median time to resolve an exception is 6.5 working days. Only 18% are resolved within 2 working days.
• About 3.1% of paid claims in the last year were paid wrongly: too much, too little, or not owed.
• Customers who wait longest are the ones most likely to leave.

Harbourline has bought Larkfield Assist to speed this up. A previous vendor built a website chatbot, ClaimBot, in 2024. It was paused when the budget ran out and nobody uses it.

The target agreed during discovery (Module 3): 70% of exceptions resolved within 2 working days, measured from the TMS and the spreadsheet and judged on the four weeks after handover, with no increase in the share of wrongly paid claims.

What the engagement builds: a claims triage assistant for the clerks. It reads an incoming exception, finds the shipment and the customer across the systems, sorts it by type and urgency, drafts a reply and a proposed payment with the policy it relied on, and leaves every decision about money to a person. It does not reply to customers on its own.

The people

At Harbourline

At Larkfield

Minor characters (a depot supervisor, a customer's site manager) may appear in a single lesson. The main cast above does not change.

Harbourline's systems

The data for all of these is in 06-shared-data.md.

The claims policy

Short on purpose, so that you can check every answer yourself.

Two rules are not in the policy. They live only in Joan's spreadsheet notes: gold-tier accounts get a late credit without argument, and the hospital (St Mary's) gets a same-day reply. Module 3 writes them down as the hidden rules R1 (gold accounts) and R2 (St Mary's, customer code C-1203, same-day reply).

Colour codes in exceptions_master.xlsx: red means blocked or waiting, amber means a credit is due, green means done.

Dates

• Course date: Friday 9 October 2026. Model names, prices, laws and documentation were checked on this day. Lessons say "(checked October 2026)".
• The engagement: Monday 16 March 2026 to Friday 5 June 2026, twelve weeks. Lessons are told in the present tense, as if you are there.
• The data date: Monday 16 March 2026, your first morning. The shared data is a snapshot from then. Code measures "how late" from that date (DATA_AS_OF), never from the computer's clock.
• Bank holidays inside the engagement: Good Friday 3 April, Easter Monday 6 April, 4 May and 25 May 2026 (gov.uk, checked 9 October 2026). They are not working days.

Key events

Lessons refer to these events. They are fixed, so that every module tells the same story. Week N starts on the Monday shown.

Facts that later lessons rely on (simulated)

Lessons add these facts as the engagement goes on. They are kept here so that every module states them the same way. All are fictional.

Systems and environment

• Mei's nightly job copies the TMS export to tms/ in harbourline-exports with a manifest (row count and checksum). Until access was approved on 17 April, Mei emailed the export each morning (Module 4, Lesson 1). Viktor's team proposes a backup copy in eu-west-1 (Module 4, Lesson 3).
• Warehouse tables: CONSMST, CUSTMST and a leftover CUSTMST_OLD (Module 4, Lesson 1).
• The data dictionary, the data contract (8 columns, 5 working days' notice of change, stop the load above 20% quarantined rows) and Joan's crosswalk of five customers, including St Mary's C-1203 to CRM ACC-505, were agreed on 25 March (Module 4, Lesson 2 and lab).
• Directory groups HF-Claims-Clerks, HF-Claims-Senior, HF-Claims-Managers and HF-Finance-Approvers, deny by default. Service account svc-claims-crm (owned by Mei, secret in AWS Secrets Manager) and IAM role claims-exports-read. ClaimBot's admin account is disabled (Module 6, Lesson 1).
• Change process: the change advisory board meets on Tuesdays. Access is by VPN plus a jump host. The pilot virtual machine sits in a private subnet with outbound traffic only through proxy.harbourline.example:8080 (Module 6, Lesson 2).
• Model route for real claims: Amazon Bedrock in Harbourline's own AWS account, region eu-west-2 (London), reached through a VPC endpoint; a self-hosted model is the fallback (Viktor's model register, Module 5, Lesson 2). The course's provider setting (Groq, Gemini or Ollama) runs on simulated data only.
• Data after 5 June: the engagement's working copies and its data processing agreement end on 5 June (delete or return). After handover, the Larkfield Assist platform processes claims under the subscription's own data processing agreement. This is story context, not legal advice (Module 4, Lesson 3).
• Larkfield Assist counts lateness in calendar days by default. A harbourline branch has patched sla.py since week 5. Ines decides on a calendar setting by 30 June (Module 13).
• Larkfield's platform team works in Toronto. Larkfield support runs an out-of-hours rota for platform faults; Harbourline IT covers its own systems (Module 14).
• Other Larkfield customers named in the course: Ashby Vale Homes (a housing association), Corran Parts (Glasgow, Scottish bank holidays) and Lowther Estates (Module 13).

History and rules

• Two earlier attempts failed before ClaimBot: a TMS replacement shelved on cost in 2021, and inbox keyword rules added by IT in 2022 and switched off at Joan's request (Module 8, Lesson 1).
• HF-88207: Atlas claims £4,800. The photos arrived in MSG-3102, but Joan's sheet was never updated and still says "waiting on photos". Module 8 finds and settles the conflict; earlier lessons report what the sheet says.
• Pilot scope: the signed scope (Module 3) named late deliveries as the first slice. D3 widened the pilot to all four exception types from 6 May, with late deliveries still the first measured slice. D3 should have been a change request (Module 11).
• Ids that share a letter: D1 to D6 are the decision log (Module 11); D2 there means a person approves every payment (a clerk up to £500, Tom above) and the assistant never replies to customers on its own. Module 2's debt register numbers its own items D1 to D10, and its lab reuses those numbers (D4 is always the calendar question). R1 and R2 are the hidden rules (Module 3); R1 to R5 in Module 11 are risks.
• Releases: 0.4.0 (CHG-0417, 5 May) starts the pilot; 0.4.1 adds Tom's weekly approval sample and keeps the pilot at three clerks; 0.5.0 (26 May) fixes St Mary's; 1.0.0 (CHG-0461, 2 June) opens it to all nine.

Commercial

• Fixed price £124,200: 12 calendar weeks at £9,000 a week, bank holidays included, plus 15% for risk. Signed 27 February 2026.
• Subscription £60,000 a year, platform costs £4,800 a year, Larkfield support days £600 each; renewal 27 February 2027.
• Loaded day cost: FDE £850, Nadia £1,000. Planned 56 FDE days and 10 of Nadia's; actual 64 and 15. Margin 50.4% planned, 40.4% actual (Module 12).
• Model prices, the exchange rate and the triage cost (£0.21 a week) are kept only in Module 5, Lesson 1, section 7, the course's one place for prices.

Placeholder people

• The six clerks other than Joan, Dev and Priti are clerk4 to clerk9. Harbourline IT's out-of-hours engineers are IT-1 to IT-4. Customer contacts from the shared inbox: Ravi Shah (Atlas), Dana Price (Northgate), Sam Okoro (Greenway).

The one-month check (simulated)

On Monday 6 July 2026, one month after handover: 7 of the 9 clerks use the assistant at least once a week, Joan among them. Over the four weeks after handover, 52% of exceptions were resolved within 2 working days, up from 18% but short of the 70% target. The share of wrongly paid claims did not rise. Mei has changed one triage rule on her own, using the runbook, without calling you: a sign that she owns it. Modules 11, 12 and 15 use these numbers; they are the only "after" numbers in the course.

The engagement, module by module

The modules follow the engagement roughly in order, though real engagements loop back. Each one adds a piece to one repository.

What "done" means

One month after you leave, is it still being used, without you?

That is the measure the whole course works towards. Almost every lesson exists to move that number.