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AI agents & workflow automation

AI agents with context, tools, and control.

We build agents that retrieve context, call scoped tools, and execute persistent workflows. Business rules, human approvals, and confirmed system writes turn model output into actions your team can trust.

System architectureStacklane engineering
Intake → Context → Review → Record
The engineering problem

A readable invoice is not a valid transaction.

The invoice, purchase order and receipt can disagree. Extraction identifies the fields; application code checks the numbers, permissions and proposed ERP action.

Example integration surface
  • Gmail / Drive
  • LangGraph
  • PostgreSQL
  • ERP API

Inside the system

One document, four explicit state transitions.

Follow a synthetic invoice from source evidence to a confirmed bill record.

Execution model01 / 04
DOCUMENT → VALIDATED STATE → APPROVED TRANSACTIONInvoice documentINV-1042 · PDF page 1Typed extractionSchema + source references100 × $84.20ERP contextPO + goods receipt100 × $81.00Deterministic checkPrice variance: +$320Review checkpointSaved state + exact payloadAUTHORIZED APPROVALJournaled writeOperation key + API scopeConfirm receiptRead back ERP recordTimeout ≠ failureLook up before retry

Swipe to inspect the full diagram →

invoice.v1Example record
invoice_id
INV-1042
line
100 × $84.20
source
PDF page 1

Follow the architecture as you scroll, or select a layer.

01

Extract a typed record

Parse the document into a schema while preserving page references. Invalid or ambiguous fields remain visible for review.

Input
Invoice PDF and source metadata
Transform
Extract fields; validate schema
Output
Typed invoice with source references
Document deduplicationRequired-field validationSource text is not policy
02

Read the matching records

Resolve supplier and purchase-order references through scoped APIs. Keep the ERP snapshot separate from the document's claims.

Input
Supplier, order and item identifiers
Transform
Read purchase order and receipt
Output
Versioned comparison packet
Explicit identity matchingRead-only context toolsFreshness checks
03

Check and checkpoint

Code calculates the variance; the model explains the discrepancy. Save the workflow state before an authorized reviewer decides whether the proposed action may proceed.

Input
Invoice, ERP snapshot and approval policy
Transform
Calculate variance; checkpoint pending decision
Output
Reviewed payload or held exception
Durable checkpointPayload-specific approvalChanged evidence invalidates approval
04

Write once, then verify

Execute the approved payload through a journaled adapter. After an uncertain response, inspect the existing operation and destination record before retrying anything.

Input
Approved payload and operation key
Transform
Execute permitted write; read back result
Output
Confirmed record or unresolved operation
No blind resubmissionDestination readbackStep-level operation journal

Inspect the behavior

Change the evidence. Inspect the route.

Three simulated runs show a confirmed match, a price exception and recovery from a lost write response.

Illustrative system · Synthetic inputs
Input

Synthetic INV-1043 matches PO-45018 at $8,100. The authorized AP reviewer has approved bill creation.

Intake: passed
Context: passed
Review: passed
Record: passed
System decision

The bill record is confirmed.

The approved $8,100 bill is read back from the simulated ERP. No payment action exists in this workflow.

invoice
INV-1043
erp_record
VB-2048
amount
$8,100.00

Verification specification

Define what passes.
Inspect what fails.

We turn expected behavior into repeatable tests and operating controls. Acceptance thresholds are agreed for your workflow, data, and the consequences of an error.

System propertyVerification methodRelease / operating condition

01Field and identity integrity

Replay malformed documents and mismatched supplier references.

Unresolved required fields prevent a proposed write.

02Approval survives interruption

Restart the worker while a review is pending.

Resume the same durable state; recheck evidence freshness.

03No duplicate transaction

Lose the write response after remote acceptance.

Confirm the existing operation before any retry.

The handover

Engineering you
can build on.

A defined implementation, reviewable evidence, and an operating model your team can own.

How we work

Workflow and tool contracts

Typed state, integration boundaries, allowed actions and approval rules.

Review and recovery interface

Source evidence, proposed changes, durable checkpoints and operation receipts.

Evaluation and operating package

Replay cases, failure injection, deployment configuration and a runbook.

Architecture decisions

Questions that
shape the build.

When does a workflow need an agent?

An agent can help when the next step depends on interpreting unstructured information or choosing between tools. We use deterministic code for calculations, policy checks, and predictable transactions. Multi-agent orchestration is appropriate when tasks benefit from separate responsibilities and can be evaluated independently.

How do agents connect to our systems?

We assess APIs, webhooks, authentication, and rate limits, then define the permitted reads and writes. Where appropriate, Model Context Protocol (MCP) exposes tools through a shared interface. We design retries and idempotency so a repeated request does not create a duplicate transaction.

Let’s scope your next build.

Bring a workflow, a product brief, or an AI system that needs to ship.

Discuss your project