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Custom models for procurement spend classification

Short answer

A custom spend classification model makes sense when supplier-based rules and your current purchasing system confuse different kinds of purchases from one supplier. Before training, agree the category split and check whether line item descriptions let you tell the categories apart, and settle the choice with a test on new line items.

How we workDetails ↓

  1. 01Call30 minutes with an engineer, free
  2. 02PrototypeA working system on your process and data, free
  3. 03ImplementationTarget and fixed price in the contract; 50% at signing
  4. 04Acceptance50% once the agreed target is met
model on your server or in the cloud in the EU
quoted after the review
same work in application with EU cloud model
from €3,000
task, data and equipment analysis
€0

We belong to the OpenAI and Anthropic partner programmes and learn through their official courses. What this means ↓

Author: Syntalith · 5 min read

Example: the morning request inbox
Agent · ready

Statistics

Purchasing and AI: statistics 2026

33 h

fewer correction hours a month at 6,000 line items: rules by supplier and description cut errors from 15% to 8%, fine-tuning to 4%. Scenario.

Figures checked: 22 October 2026

Before ordering a spend model
  • A category split agreed with the report's owner
  • Line item descriptions that let you tell categories apart
  • The result of current rules and the system on new line items
  • A person who checks line items with no clear category

One supplier, different purchases

Take an illustrative manufacturing company. The same distributor supplies it with protective gloves and machine spare parts. A rule that assigns all spend with the distributor to safety equipment gives a technically consistent report, and it hides maintenance spending. When the team plans a joint purchase of gloves with other plants, it works from the wrong basis.

A model that reads individual line items could separate these purchases, if it gets information that lets it recognise them. The description “protective gloves” tells you something different from “materials as per order”. In the second case a link to the purchase order may be needed. Using a more complex model will not fill in the missing context reliably.

In a pilot, assess line items with a clear description separately from those that need extra documents. If the improvement depends mainly on access to orders, connecting the data will be a key part of the project. Buying training alone will leave that problem unsolved.

Who decides which spend category an expense belongs to

A procurement taxonomy is an ordered split of spend into categories and subcategories. It should match the decisions the purchasing team takes. An accounting account describes a different dimension of the records; do not assume its code is enough to set the category used in negotiations. A project can use both pieces of information while keeping their meanings separate.

Before choosing technology, name the person responsible for the split and for settling disputes. In the distributor example, purchasing and maintenance have to agree where spare parts go. If each plant uses the same name for a different scope, a shared report will not be comparable even after AI is rolled out.

Before classifying spend, you need agreements with the report owners on the category split and the quality of the training data. For the buyer, that means checking whether the history of assignments reflects the current split. Good results at reproducing old categories may be of little value when the company is changing them.

What to compare before ordering your own model

Rules assigned to suppliers are worth checking where the company buys a clearly defined range from them. They are easy to explain to the team. For a distributor serving several areas, though, they need extra information about the line item.

If your current purchasing system has a spend classification feature, include it in the comparison. Check the category split it supports and whether its results can feed your current reports. Your own app has to justify the work needed to maintain it and connect it to your systems.

A general model can be assessed on understanding descriptions and assigning them to the agreed categories. When recurring errors specific to the company's range remain, a custom classifier or fine-tuning, adapting an existing model through further training, becomes a candidate for further testing. Fine-tuning is no mandatory stage and no guarantee of a better result.

The comparison should also cover handling exceptions. A solution that recognises frequent purchases correctly, but hands most harder line items to analysts, may still need a lot of work. Know that effort before you decide on a rollout.

How to accept the pilot result

Ask for the methods to be compared on the same, previously unseen line items. They should include both known suppliers and purchases from companies the model did not meet during adaptation. Such a test helps you tell recognising the type of purchase apart from relying on a familiar supplier name.

The overall result has to be broken down by category and by the effect of errors. Confusing two subcategories of gloves can matter differently from counting machine parts as safety equipment. Also assess the value of wrongly assigned spend: a few large line items can change the picture of a category even when many small purchases are classified correctly.

Agree what the system does with a description that does not allow a category to be chosen. You need a person who checks such line items and a way to pass them the context. Purchasing systems with spend classification often show the confidence of an assignment and allow manual correction, which is a reference point when you assess the team's workload. For your own project, check whether the confidence indicators help catch errors on the company's data.

Also set the point at which a result may feed the report. A proposed category waiting for review and an accepted assignment should be distinguishable to the reader of the analysis. The pilot scope can include a comparison report, a review of errors and a recommendation for next steps with its limits.

The scope of the rollout and ongoing responsibility

New suppliers and changes to the range can change the kind of descriptions that reach classification. A separate event is a rebuild of the categories, for example splitting spare parts out of the wider maintenance area. In both cases the results have to be assessed again, and only the second changes the definition of a correct answer. The offer should state who reports such changes and how the scope of updates is set.

Syntalith builds AI apps and solutions with custom models, as well as automations and custom software. For spend classification, this lets us consider the model, access to purchasing data and the handling of corrections together. What remains to agree is which parts the pilot covers and which a separate rollout does. We price a private model after a free call about the task, the data and the hardware. An app that uses the model starts from €3,000 net (pricing).

In your enquiry, describe the report you do not trust today and the purchasing decision that depends on it. Name the system you use, the information available about line items and the person responsible for the categories. Also prepare examples of errors and how they are checked today. From that you can settle whether the first order should be a comparison of classifiers, tidying the categories or access to the missing data.

What a spend classification model costs and what it saves

Scenario: 6,000 line items a month
Today: 15% errors × 6,000 × 3 min
45 h × €34.90 = €1,571
After a change without training (rules by supplier and description): 8%
24 h (€838)
After fine-tuning: 4%
12 h (€419)

Fine-tuning saves another 12 h (€419) a month beyond the simpler change

The error shares and the correction time are the scenario's assumptions, which we measure on cases not used for training. €34.90 an hour is the EU average hourly labour cost for 2025 according to Eurostat.

The comparison before the decision
  • Cases for assessment kept apart from training examples
  • The same set for the current solution, the simpler change and the new model
  • Decisions by the people who correct the results today
  • Errors counted separately for each type of mistake

Where to start

In the free process review we choose one process and 20 to 100 cases the team has already handled. We compare the simpler change with the adapted model on cases the model has not seen, and within 2 working days you get a written summary with a price. We adapt models as part of private LLMs, and build the app as an AI app.

Worked example · Scenario

How we count the payback: spend categories

We run the same count for your purchasing team in the free process review.

€2,792

a month for checking 800 supplier invoices by hand

Payback: 1.3 mo.

6 minutes to compare an invoice with the order and the goods receipt and checking in 15% of the old time are our assumptions. €34.90 an hour is the EU average hourly labour cost for 2025 according to Eurostat, for companies with 10 or more employees. Model cost: €0.0040 per invoice, measured in our invoice coding system (0.004514 USD), at the ECB rate of 1.1205 USD per euro on 22 October 2026.

See the full calculation →

This is how we implement it in companies

All case studies →

Client results.

All projects →
foap.comcustomer service

foap.com customer service: 95% of replies are sent automatically.

Users from several countries write to foap.com, in several languages. The system reads the entire conversation and the terms of that person, and then sends a response in that person's language. Questions about money and exceptions go to the team with a ready draft, so they have to check and send them.

the system sends the answers itself, without human typing
95%
time from the arrival of the e-mail to the ready response (median)
30 s
e-mails that require a response receive a ready-made draft
100%
less work for every 1000 answers (estimate)
47 h

Data from foap.com production, October 20-21, 2026. Estimate: 3 minutes for handwritten response.

How foap.com customer service works →
Sample messages. Money matters always come to the person.

Other implementations

jaktako.design

studio projektowe

−87%

Time to look for new customers, every day

4 hours → 30 min

approx. 73 hours less per month (21 days of work)

according to the studio

How the agent loop works →
Signature Estates

real estate

approx. −90%

Operator time spent browsing portals, per day

2–3 hours → 20 min

approx. 45 hours less per month (21 days of work)

respect · contact the seller 5 minutes after the announcement

How the agent finds property listings →
Kuba Koziej, CEO and co-founder of MoreGrowth and board member at Natu.Care

Kuba Koziej

CEO and co-founder, MoreGrowth

„We started with my own AI agent. During the training that followed, I learned to build new applications myself. Today I am bringing this way of working with AI into my business. Working with Syntalith gave me exactly the skills and tools I needed.”

View the original training review on LinkedIn ↗

A model on your server or in the cloud in the EU, proven on your tasks.Book a free process review (30 min) →

How we build automation and agents

From a conversation to a working system in four steps.

  1. 01 · 30 min

    Free process review

    €0

    You're talking to an engineer. You receive the written plan within 2 business days.

  2. 02 · 5 days

    Free prototype

    €0

    The system works on 20-100 cases that your team has already handled. You see every result.

  3. 03 · 2–16 weeks

    Build

    50%

    Fixed price and goal written in the contract. First installment upon signing.

  4. 04 · after reaching the goal

    Reception

    50%

    You pay the second installment when the system reaches its target on your cases.

How a free prototype is created

Mon.

We set a goal

What result do you consider good?

Tue–Wed

The system is working

It goes through your affairs, one by one.

Thu

We compare

We check every difference with the team's work.

Fri

Result and price

List of errors and fixed implementation price.

You choose the matters. We anonymize them upon request, they stay in the EU and we delete them after the test.

On the market, such a test usually costs from PLN 3,000 to PLN 8,000.

Book a free process review (30 min)

We establish a prototype during a free analysis.

Data checked on October 25, 2026.

„Is my data safe?”

Yes. You choose where they go: from your company account to the model on your server.

  1. 00Employee's private account

    Customer and company data ends up in an account that the company cannot see or control. There is no data processing agreement, so it is a violation of the GDPR. When an employee leaves, the chat history goes with them.

  2. 01ChatGPT or Claude corporate account

    The provider does not use your data to train models. A copy of the queries remains in his logs for up to 30 days.

  3. 02API with zero retention (ZDR)

    The provider processes the request and does not save anything. It requires his consent, we prepare the application together.

  4. 03Processing in the EU

    Queries are counted and stored in Europe: OpenAI in the EU region, Claude via clouds with the EU region.

  5. 04Model at your place

    The open model runs on your server or in your cloud in the EU. The data does not go outside the company.

What we do with every implementation

  • Confidentiality agreement and data processing agreement before we receive any data.
  • You choose the cases for the prototype and we anonymize them upon request.
  • The data stays in the EU and we delete it after the test.
  • Corporate accounts with an administrator on your side.

When data cannot leave the company

The open model runs on your server or in your cloud in the EU. To choose from:

White-tailed eagle
Polish model, SpeakLeash and ACK Cyfronet AGH
PLLUM
Polish model, HIVE consortium commissioned by the Ministry of Digitization
Qwen
Alibaba
GLM
Zhipu AI
DeepSeek
DeepSeek

We select a model for the task and check it on your cases. We run it, tune it and maintain it.

Source: Bielik and PLLuM, ACK Cyfronet AGH ↗ · PLLuM, Ministry of Digitization ↗

Do you have a lot of your own data? We will fine-tune the small model.

  1. 1 Your examples
  2. 2 tuning
  3. 3 test on new cases
  4. 4 model at your place

When you have thousands of similar emails, documents or reports, we teach a small open model based on your examples. It works for you, responds quickly and costs less to maintain than a large model. We measure quality on issues that the model has not seen while learning.

Przemysław and Piotr did it in large programming and consulting companies. Artem did it before and does it today at Syntalith. It's about models on your own infrastructure, tuning and quality measurement.

You choose the protection level during the interview. We sign the data processing agreement before we see any data.Schedule a free analysis →

Private AI models

A model on your server or in the cloud in the EU, proven on your tasks.

We select the model and equipment for the task, run it and measure the quality using your examples before you buy anything. The data stays in the company or in the cloud in the EU. We price implementation, hardware or hosting and support separately after analysis.

View private AI models →
model on your server or in the cloud in the EU
quoted after the review
same work in application with EU cloud model
from €3,000
task, data and equipment analysis
€0

Questions

  • When is it worth building a spend category model?

    When supplier rules confuse different kinds of purchases, the categories are agreed and line item descriptions let you tell them apart. A test on new line items settles the choice.

  • Is the history of assignments enough for training?

    Only when it reflects the current category split. Reproducing old categories well is of little value when the company is changing them.

  • How much does fine-tuning a model cost?

    An AI app at Syntalith costs from €3,000 net, and we price adapting the model after comparing it with a simpler change on cases the model has not seen. In the scenario, fine-tuning saves another 12 hours a month beyond what rules by supplier and description give.

Let's talk

Just write, call or choose a date.

We work fast because we hate corporate cotton wool. We don't have salespeople or managers to keep an eye on managers. You talk immediately to engineers who then build your system. We respect each other's time and yours too.

We will accept 3 more companies by the end of the year.

Mon–Fri 9:00–17:00 CET

What our OpenAI and Anthropic partnerships mean for you.

OpenAI makes ChatGPT and Anthropic makes Claude. We belong to the partnership programs of both companies, so we work with their tools every day and learn from the creators themselves.

OpenAI Select PartnerClaude Partner Network
01We will select a tool for the task
We implement both ChatGPT and Claude. We check both on your documents, and you choose the one that makes fewer corrections and saves more time.
02Knowledge straight from the creators
We learn from official OpenAI and Anthropic courses and materials. Your team learns about the features and settings that work today.
03Licenses without our margin
When we roll out ChatGPT, Claude or Copilot, you buy the licences directly from OpenAI, Anthropic or Microsoft and they invoice you. We add nothing to the licence.
04Certified engineers
On the team, we have an AWS certification in machine learning and an Anthropic certification in systems architecture on Claude.

Participation in programs does not mean that OpenAI or Anthropic endorses our services.