Pattern Library

The pattern library (@bpmnkit/patterns) provides domain knowledge for common business processes. When you run /bpmnkit:implement, Claude checks the library for a matching pattern (casen pattern list/get) and uses its readme and worker specs as context while writing the ProcessPlan — the pattern’s own template field predates the plan/synth pipeline and is a rough structural reference, not something pasted in directly.

Patterns are hints, not templates. Claude adapts them to the specific request and ignores them entirely when nothing relevant matches.

Available patterns

Pattern ID	Domain	Typical use
`invoice-approval`	Finance / accounts payable	Multi-level invoice review and ERP payment trigger
`employee-onboarding`	HR	Account provisioning, orientation scheduling, system access
`supplier-contract-review`	Procurement / legal	Contract classification, risk scan, CLM storage, e-signature
`incident-response`	IT / ops	Severity classification, on-call paging, post-mortem creation
`loan-origination`	Financial services	Identity verification, credit check, risk scoring, disbursement
`content-moderation`	Trust & safety	AI scan, action enforcement, CSAM reporting, user notification
`order-fulfillment`	E-commerce / supply chain	Inventory validation, payment, warehouse order, shipment tracking

How matching works

casen pattern get <query> (via findPattern()) scores each pattern by counting how many of its keywords appear in the request. The highest-scoring pattern is selected. Exact pattern ID matches take priority over keyword scoring.

Examples:

Request	Matched pattern
”invoice approval workflow”	`invoice-approval`
”employee onboarding with Okta and Jira”	`employee-onboarding`
”on-call incident escalation”	`incident-response`
”custom blockchain process”	(no match — Claude works from scratch)

What a pattern contains

Each pattern has four components:

README — domain context, common variations, relevant regulations, and conventions. Claude reads this before generating the BPMN.

Template — a compact BPMN template in the BPMNKit intermediate format (not raw XML). Used as a starting-point structure, not a fixed output.

Worker specs — typical service tasks with job type, inputs, outputs, and real integration options (e.g. “SAP, NetSuite, or QuickBooks” for a payment trigger).

Variations — common process variants (e.g. “3-way match”, “auto-approve below threshold”) so Claude can adapt the flow to the user’s specific context.

Using patterns from the CLI

casen pattern list
casen pattern get invoice-approval
casen pattern get "employee onboarding workflow"   # free-text match

Using patterns from code

You can access the pattern library directly in TypeScript:

import { ALL_PATTERNS, findPattern } from "@bpmnkit/patterns"

// List all patterns
console.log(ALL_PATTERNS.map((p) => p.id))

// Find by keyword match
const pattern = findPattern("employee onboarding workflow")
console.log(pattern?.id)  // "employee-onboarding"

// Find by exact ID
const invoice = findPattern("invoice-approval")
console.log(invoice?.workers.map((w) => w.jobType))

Pattern schema

interface Pattern {
  id: string
  name: string
  description: string
  keywords: string[]
  readme: string                // domain context, Markdown
  workers: WorkerSpec[]
  variations: string            // common customizations, Markdown
  template: PatternTemplate     // compact BPMN structure — a rough reference, predates ProcessPlan
}

interface WorkerSpec {
  name: string
  jobType: string
  description: string
  inputs: Record<string, string>
  outputs: Record<string, string>
  externalApis?: string[]  // e.g. ["Stripe", "Adyen", "Braintree"]
  optional?: boolean
}

Adding custom patterns

Create a new pattern file in packages/patterns/src/patterns/ and export it from index.ts. Follow the existing patterns as a reference — each is a single TypeScript file that exports a Pattern object.

For private or organisation-specific patterns, add them to your project and contribute the pattern object to ALL_PATTERNS via the findPattern API. Contributions to the seed library are welcome via pull request.