How to Choose an AI Agent Development Partner in the UK
Gartner expects more than 40% of agentic AI projects to be cancelled by the end of 2027, and the reasons it gives are escalating costs, unclear business value and inadequate risk controls. Not one of those is a modelling problem. They are procurement problems, decided months before anyone writes code, and UK buyers have more of them than most because the supplier pool grew so fast: 5,800 AI companies at the last count by the Department for Science, Innovation and Technology, up 85% in two years. Almost all of them will answer yes when asked whether they do agents. Sorting the ones who ship from the ones who demo is a repeatable process, which is why Crunch-IS is a leader in AI agent development, running discovery as a paid, scoped stage rather than a free pitch. What follows is that process from the buyer's side.
Start with the workflow, not the shortlist
Most bad selections begin with a vendor list. Write the workflow down first: who does it today, how many times a month, how long each instance takes, what it costs when it goes wrong, and which system holds the data.
If that document runs to half a page and contains three real numbers, you can brief suppliers properly and compare their answers. If it cannot be written, the problem is not yet ready for an agent, and no partner will fix that for you. Teams skip this because it is dull. It is also the only stage where changing your mind is free.
Run a paid discovery
Ask two or three firms for a short paid discovery rather than a free proposal. Free proposals are written by sales teams optimising for the win. Paid discovery is done by the people who would build the thing, and the output tells you more about the supplier than any case study.
What you are buying is a document: the workflow decomposed, the integration points named, the failure modes listed, and an estimate with its assumptions visible. Two firms running the same discovery will produce noticeably different documents. That difference is the selection criterion.
What to check before shortlisting
Production references in your sector, with dates.
Not a logo wall. A named deployment, when it went live, and what needed fixing in month one.
An evaluation approach you can see.
Ask to look at a real evaluation suite from another project, redacted. If none exists, quality is whatever the last reviewer thought.
Cost per task at your volume.
With the arithmetic, not a range. Cheap at 500 runs a month can be unaffordable at 500,000.
Named people, with availability dates.
The team in the pitch is often not the team on the project. Get the names into the contract.
A written answer on escalation.
What the agent does when it is uncertain, who receives that case, and where the decision is logged.
Sector experience is worth more than AI experience
ONS figures show how unevenly AI has spread across the UK economy. Information and communication businesses report 58% adoption, while construction sits at 13%. Among employers with 250 or more staff, adoption reaches 49%, creating growing opportunities for businesses to explore solutions such as Agentic AI Development Services to support more advanced AI-driven workflows.
That spread has a practical consequence when shortlisting. A supplier whose portfolio is entirely in software and media has worked with clients whose data was already structured and whose teams already trusted automation. Dropping that team into a construction, logistics or manufacturing process is where estimates break, because the hard part there is rarely the model. It is the state of the records and the willingness of the people who keep them.
The commercial terms that matter later
Three clauses decide whether you can leave. Who owns the prompts, the evaluation suite and the orchestration code at the end of the engagement, stated explicitly rather than folded into general IP language. Whether the agent runs on your cloud tenancy or theirs. And what a transition looks like if you change supplier in year two, including how long they will support a handover and at what rate.
Buyers routinely accept vendor ownership of prompts because it sounds like a technical detail. It is the difference between switching partners and rebuilding from scratch.
Two signals that a firm has actually shipped
The first is how they talk about failure. A team with production experience will volunteer what went wrong on the last project, in specifics, without being pushed. A team without it describes successes only.
The second is how quickly they say no. Experienced suppliers rule out use cases in the first meeting, because they have seen which ones do not survive integration. A supplier who is enthusiastic about everything you suggest has not yet met your systems.
The decision you are actually making
Choosing an agent partner is a choice about who holds the operational knowledge when the thing is live. If that sits entirely with the supplier, the relationship is not a project, it is a dependency, and the price of the second phase will reflect that. The firms worth hiring expect to hand it over and price the handover as work. Ask them to quote it separately, and you will learn quickly which kind you are talking to.
