AI agent development

AI agents that hold up when the demo audience leaves

Most agent projects die between the impressive prototype and the first thousand real cases. We build the unglamorous layer that closes that gap — grounded retrieval, validated tool calls, evaluation suites and escalation paths — so the agent still works in month six.

  • 8-12 weeks to production
  • Fixed-price 2-week scoping sprint
  • Claude
  • OpenAI
  • LangGraph

What is ai agent development?

AI agent development is the engineering work of turning a language model into a system that completes a business process on its own — reading from your systems, deciding what to do, taking action through tools, and escalating to a human when it is not confident. The hard part is not the model. It is the retrieval, the tool contracts, the guardrails, the evaluation suite and the observability that keep the agent correct once it is handling thousands of real cases a day rather than five in a demo.

Why teams call us

What usually goes wrong before we get involved

Almost every engagement starts from one of these. If none of them sound familiar, you probably do not need us yet.

The demo worked, production did not

A prototype tested on a dozen hand-picked cases hides everything that matters. Real inputs are messier, real users ask things the prompt never anticipated, and the long tail of edge cases is where the process actually spends its time. Without an evaluation set drawn from your own historical cases, nobody discovers this until the agent is live.

Typically 2-3 months of rework, plus the internal credibility cost of a visible failure.

No one can tell whether a change helped

Teams without an evaluation harness end up tuning prompts by vibe. Someone changes a wording, it looks better on the three examples they checked, and a regression ships silently. Six weeks later the agent is measurably worse than at launch and there is no record of which change caused it.

Quality drifts downward invisibly until a customer or auditor finds it.

The agent can do more than anyone intended

Agents are given broad credentials early because it is faster, and the permissions are never narrowed. The result is an autonomous system with write access to production data, no spend ceiling, no approval step on high-impact actions, and no audit trail that would let you reconstruct what it did.

One incident is usually enough to get the whole programme paused.

Token spend scales worse than usage

Routing every step through a frontier model — including classification, extraction and routine formatting — makes unit economics collapse as volume grows. The bill is fine in pilot and indefensible at scale, and by then the architecture assumes one model everywhere.

Commonly 4-10x more inference spend than the same workload needs.

Scope

What ai agent development covers

Agent architecture and task decomposition

We start by deciding what should not be an agent. Deterministic steps stay deterministic; the model is used only where judgement is genuinely required. That single decision is the difference between a system you can debug and one you cannot.

  • Process mapping to separate rule-based steps from judgement steps
  • Single-agent versus multi-agent decision, with the reasoning written down
  • State and memory design, including what the agent must deliberately forget

Tool and system integration

Agents are only as useful as the actions they can take. We build typed tool contracts against your CRM, ERP, ticketing, database and internal APIs, with validation at the boundary so a malformed model output can never reach a system of record.

  • Schema-validated tool definitions with structured output enforcement
  • Idempotency and retry semantics for actions that must not double-fire
  • Least-privilege credentials scoped per tool, not per agent

Grounded retrieval

An agent reasoning over stale or irrelevant context will confidently do the wrong thing. We build the retrieval layer — chunking, hybrid search, reranking, freshness handling — and make every answer traceable to the source document it came from.

  • Hybrid keyword and vector retrieval with reranking
  • Citations on every claim, linked to the source the user can open
  • Retrieval quality measured independently of end-to-end agent quality

Guardrails and human-in-the-loop design

We classify every action by blast radius and design the approval path accordingly. Reversible, low-impact actions run autonomously; anything that moves money, touches a customer record or cannot be undone gets a human checkpoint.

  • Action-level permission model with enforced spend and volume ceilings
  • Confidence thresholds that route uncertain cases to a named queue
  • Full decision audit trail, exportable for compliance review

Evaluation harness

We build an evaluation set from your real historical cases, including the ones that went wrong, and wire it into CI. Every prompt, model or retrieval change is scored against it before it ships.

  • Golden dataset assembled from your own transcripts and records
  • Automated scoring for accuracy, grounding, tone and refusal correctness
  • Regression gates that block a deploy on a quality drop

Observability and cost control

Once live, you need to see quality, latency and cost per action — not just error logs. We instrument traces end to end and route each step to the cheapest model that passes evaluation for it.

  • Per-step tracing with token and latency attribution
  • Model routing so routine steps do not run on frontier pricing
  • Alerting on quality regression, not only on exceptions

How it runs

The delivery process

Fixed checkpoints with a named deliverable at each one, so you can stop the engagement at any stage and still own something useful.

  1. Scoping sprint

    Weeks 1-2

    Two weeks, fixed price. We map the process end to end, identify which steps genuinely need a model, assemble the first version of the evaluation set from your historical data, and produce an architecture with a cost and latency model. If the honest conclusion is that this should not be an agent, that is what the document says.

    You receive: Written architecture, evaluation plan, cost and latency model, build estimate — yours to keep either way.

  2. Thin vertical slice

    Weeks 3-5

    We build the narrowest complete path through the process — one real case type, running against real systems, with retrieval, tool calls, guardrails and logging in place. It goes to a small internal group so the failure modes surface while they are cheap to fix.

    You receive: Working agent handling one case type end to end in a staging environment.

  3. Evaluation and hardening

    Weeks 5-7

    The evaluation suite is expanded to cover the long tail, and we work the failure modes it exposes: retrieval gaps, ambiguous instructions, tool errors, adversarial inputs. This is the phase most projects skip, and skipping it is why they fail.

    You receive: Evaluation suite in CI with a documented baseline score and regression gates.

  4. Production rollout

    Weeks 7-9

    We ship behind a feature flag, ramp traffic in stages, and keep a human review queue oversized at first so errors are caught by us rather than by your customers. Ramp decisions are made on evaluation and incident data.

    You receive: Agent live on production traffic with monitoring, alerting and rollback in place.

  5. Handover or operation

    Week 10 onward

    Either your team takes it — with documentation, a recorded architecture walkthrough and paired sessions on the evaluation tooling — or we operate it on a retainer. We will tell you which is cheaper for you over two years.

    You receive: Runbook, architecture documentation, evaluation ownership, and a monthly quality review.

What you end up owning

  • Agent architecture document covering state, tools, retrieval and failure handling
  • Evaluation suite built from your historical cases, running in CI
  • Typed, schema-validated tool integrations against your existing systems
  • Action-level permission model with audit logging
  • Observability dashboards for quality, latency and cost per action
  • Runbook and recorded walkthrough for your on-call engineers
  • Source code in your repository, under your licence, with no runtime lock-in

Typical stack

  • Claude
  • OpenAI
  • LangGraph
  • Pydantic AI
  • Temporal
  • pgvector
  • LangFuse
  • Python
  • TypeScript

Engagement

Typical timeline
8-12 weeks to production
Starting at
Fixed-price 2-week scoping sprint
Engagement models
Fixed-price scopingMilestone-based buildEmbedded with your teamManaged operation retainer

Results

What this typically moves

Scoping to first production traffic
6-10 weeks
Typical autonomous resolution on well-scoped processes
60-80%
Inference cost reduction from model routing
4-8x
Agent decisions captured in an audit trail
100%

Why most AI agent projects stall after the prototype

Building something impressive with a language model is now easy. A competent engineer can wire up a tool-calling loop over a weekend and produce a demonstration that makes a leadership team genuinely excited. That is the trap: the prototype is the cheap 20% of the work, and it creates the impression that the remaining 80% is a formality.

It is not. The prototype succeeds because it runs on a handful of clean, chosen examples. Production fails because real inputs are ambiguous, the process has a long tail of exceptions nobody documented, source systems return unexpected nulls, and users ask for things outside the intended scope on their first day.

The work that closes that gap is unglamorous and mostly has nothing to do with prompts. It is retrieval quality. It is validating model output against a schema before anything acts on it. It is deciding which actions require human approval. It is building an evaluation set so a change can be measured rather than guessed at. None of that demos well, and all of it determines whether the agent is still running in six months.

What an AI agent actually is, technically

Strip away the marketing and an agent is a loop with four parts:

  1. Perception — it reads state from somewhere: a ticket, a database row, a document, an event, a user message.
  2. Reasoning — a model decides what should happen next, given that state and the goal it was given.
  3. Action — it calls a tool: a function with a defined signature that queries or changes something in a real system.
  4. Evaluation — it checks whether the goal is met, and either loops or stops.

Everything that distinguishes a production agent from a prototype lives in the constraints around that loop. How many iterations before it gives up. What it is permitted to call. What happens when a tool errors. What confidence level is required before it acts unsupervised. How a human takes over mid-task. Whether you can reconstruct, three months later, exactly why it made a particular decision.

Where the engineering effort actually goes

On the agent builds we have shipped, the effort distribution is consistently lopsided:

AreaShare of effortWhy it dominates
Retrieval and data plumbing~30%Agents fail on context quality far more often than on reasoning quality.
Tool contracts and integration~25%Every system has undocumented behaviour, and the agent finds all of it.
Evaluation and testing~20%This is the only thing that makes quality measurable rather than anecdotal.
Guardrails and permissions~15%Blast radius has to be designed, not discovered after an incident.
Prompting and model selection~10%Real, but the smallest slice — and the easiest to change later.

Teams that expect the reverse distribution — most effort on prompts — are the ones that get surprised.

The evaluation set is the project

If we could enforce only one practice, it would be this: before writing agent logic, assemble a set of real historical cases with known correct outcomes, including the awkward ones and the ones a human got wrong.

That set becomes the thing you optimise against. It turns “this prompt feels better” into a number. It catches the regression introduced by a model version change. It gives you a defensible answer when someone asks how accurate the system is. And it is the only mechanism we know of that stops slow quality decay over months of small changes.

Building it takes real work — usually a week of pulling records and adjudicating correct answers with someone who knows the process. Teams resist it because it feels like a detour. It is the shortest path.

Guardrails: constrain capability, do not just instruct

A recurring mistake is treating safety as a prompting problem — writing “never issue a refund above $500” into the system prompt and considering it handled. Instructions are the weakest available control. They are probabilistic, and a sufficiently unusual input will route around them.

The controls that hold are structural, and they sit outside the model:

  • Capability scoping. The agent has credentials for exactly the systems it needs, at exactly the access level it needs. If it cannot call the refund API, no prompt injection makes it issue a refund.
  • Schema validation. Model output is parsed and validated before it becomes an action. A malformed or out-of-range value is rejected at the boundary.
  • Enforced limits. Spend ceilings, rate limits and volume caps live in code, not in instructions.
  • Approval gates. Actions classified as high blast radius stop and wait for a named human.
  • Audit trail. Every decision is logged with the context that produced it, so an incident can be reconstructed rather than speculated about.

Cost: the architecture decision that shows up on the invoice

The most common unit-economics mistake is running every step through a frontier model. Agent workflows are full of routine steps — classifying an intent, extracting a field, formatting an output — where a small model performs identically at a fraction of the price.

We benchmark step by step and route each one to the cheapest model that passes evaluation for that step, keeping frontier models for the genuinely judgement-heavy parts. On high-volume workloads this routinely cuts inference spend by four to eight times with no measurable quality change. Doing it later is harder, because by then the architecture assumes one model everywhere.

What working with us looks like

We start with a fixed-price two-week scoping sprint, and its output is yours whether or not you continue: architecture, evaluation plan, cost model, estimate. We do that because a scope you cannot take to another vendor is not a scope, it is a lock-in mechanism.

Sometimes that document concludes you should not build an agent — that the process needs fixing first, or that a deterministic workflow would be cheaper and more reliable. We would rather write that in week two than bill you for twelve weeks of building the wrong thing.

Frequently asked questions

What is the difference between an AI agent and a chatbot?
A chatbot produces text. An agent takes actions — it queries your database, updates a ticket, issues a refund, books a slot, calls another service — and decides on its own which action to take next. That difference is why agents create real operational leverage and also why they carry real risk: a chatbot that is wrong gives a bad answer, while an agent that is wrong changes something in your system of record. Every agent we build therefore ships with scoped permissions, a reversible action design where possible, and an audit log of every decision.
How much does AI agent development cost?
For a single well-scoped agent handling one process, most engagements land between a two-week fixed-price scoping sprint and a build measured in milestones over six to twelve weeks. The cost drivers are almost never the model tokens. They are the number of systems the agent has to integrate with, how clean your data is, how strict the compliance review is, and how many edge cases the process genuinely has. We give a range on the first call and a firm number at the end of scoping.
How long does it take to build a production AI agent?
Six to ten weeks from the end of scoping to real users on real data, for a typical mid-size company. What sets that timeline is rarely the engineering. It is getting credentialed access to source systems, passing security review, and getting a decision on who owns the agent's mistakes. We front-load all three in week one because they are the things that slip.
How do you stop an AI agent from doing something harmful?
By constraining what it is able to do rather than only instructing it not to. In practice that means: every tool the agent can call has a schema and validated inputs, high-impact actions require a human approval step, spending and volume limits are enforced outside the model, the agent cannot reach systems it was not explicitly granted, and every decision is logged with the inputs that produced it. Prompt instructions are the weakest layer of that stack, so we never rely on them alone.
Should we build AI agents in-house or hire an agency?
Build in-house if agentic AI will be a permanent core competency, you can compete for the talent, and you have the runway to learn the failure modes on your own traffic. Bring in a partner when you need the first system working this quarter, when the failure modes are unfamiliar and expensive to discover live, or when you want your own engineers to learn by building alongside people who have already made those mistakes. We are explicit about which case you are in, including when the answer is that you do not need us.
What happens to the agent after it launches?
Model providers deprecate versions, your data changes shape, and usage patterns move — so agent quality decays without maintenance. Post-launch we run the evaluation suite on a schedule, monitor cost and latency per action, alert on quality regressions rather than only on errors, and review degradation monthly. Teams that take the handover get the same tooling plus a walkthrough of how to read it.

Next Step

Tell us what you are trying to automate

A 30-minute technical call with an engineer who has shipped this before — not a sales qualification round. You leave with a feasibility read, a rough shape for the build, and an honest answer about whether it is worth doing at all.

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