business-rules-analysis

What this skill does

# Business Rules Analysis

Comprehensive framework for eliciting, documenting, and validating business rules during requirements discovery.

## When to Use This Skill

**Keywords:** business rules, policies, constraints, calculations, derivations, inferences, decision tables, decision logic, rule templates, validation rules, authorization rules, computation rules, condition-action, if-then rules

**Use this skill when:**

- Identifying business policies and constraints
- Documenting calculation and derivation rules
- Creating decision tables for complex logic
- Eliciting authorization and validation rules
- Translating policies into requirement statements
- Analyzing rule interactions and conflicts
- Validating rule completeness and consistency

## Business Rule Categories

### Structural Rules (Facts)

Define the nature of things and relationships:

```yaml
structural_rules:
  definition: "Rules that define terms, concepts, and their relationships"

  types:
    terms:
      description: "Definitions of business concepts"
      example: "A 'Premium Customer' is a customer who has spent more than $10,000 in the last 12 months"

    facts:
      description: "Assertions about the business domain"
      example: "Each Order must have exactly one Customer"

    relationships:
      description: "How concepts relate to each other"
      example: "A Customer may have zero or more Orders"

  documentation_template:
    term: "{Term} is defined as {definition}"
    fact: "{Subject} {verb} {object}"
    relationship: "{Entity A} {cardinality} {Entity B}"
```

### Derivation Rules (Computations)

Calculate or derive values from other data:

```yaml
derivation_rules:
  definition: "Rules that compute values from other information"

  types:
    calculations:
      description: "Mathematical computations"
      example: "Order Total = Sum of (Line Item Quantity × Unit Price)"

    aggregations:
      description: "Summary calculations across sets"
      example: "Monthly Revenue = Sum of all Order Totals for the month"

    transformations:
      description: "Data conversions"
      example: "Full Name = First Name + ' ' + Last Name"

  documentation_template:
    calculation: "{Result} = {formula}"
    with_conditions: "IF {condition} THEN {Result} = {formula}"
```

### Constraint Rules (Restrictions)

Limit what can happen or exist:

```yaml
constraint_rules:
  definition: "Rules that restrict or mandate conditions"

  types:
    mandatory:
      description: "Must always be true"
      example: "Every Order must have at least one Line Item"

    prohibited:
      description: "Must never occur"
      example: "An Order cannot be shipped to a country on the embargo list"

    conditional:
      description: "Restrictions that apply under certain conditions"
      example: "IF Customer is under 18 THEN alcohol products cannot be ordered"

    range:
      description: "Numeric or value boundaries"
      example: "Order Quantity must be between 1 and 999"

  documentation_template:
    must: "{Subject} must {condition}"
    must_not: "{Subject} must not {condition}"
    if_then: "IF {condition} THEN {subject} {must/must not} {action}"
```

### Action Rules (Behaviors)

Define what should happen when conditions are met:

```yaml
action_rules:
  definition: "Rules that trigger actions based on conditions"

  types:
    authorization:
      description: "Who can do what"
      example: "Only Managers can approve orders over $5,000"

    triggers:
      description: "Events that initiate actions"
      example: "When inventory falls below reorder point, create purchase order"

    workflows:
      description: "Sequences of actions"
      example: "After order is placed, send confirmation email, then notify warehouse"

  documentation_template:
    authorization: "{Role} may/must/must not {action} {object} [when {condition}]"
    trigger: "WHEN {event} THEN {action}"
    workflow: "AFTER {event}, {action1}, THEN {action2}"
```

### Inference Rules (Deductions)

Derive new facts from existing information:

```yaml
inference_rules:
  definition: "Rules that infer new information from existing facts"

  types:
    classification:
      description: "Categorize based on criteria"
      example: "IF Customer lifetime value > $50,000 THEN Customer is 'VIP'"

    status:
      description: "Determine state based on conditions"
      example: "IF all line items shipped THEN Order status is 'Complete'"

    eligibility:
      description: "Determine if conditions are met"
      example: "Customer is eligible for discount IF loyalty points > 1000"

  documentation_template:
    inference: "IF {conditions} THEN {conclusion}"
    classification: "{Entity} is classified as {category} WHEN {criteria}"
```

## Decision Tables

For complex rules with multiple conditions:

```yaml
decision_table:
  structure:
    conditions: "Rows listing input conditions"
    actions: "Rows listing possible actions"
    rules: "Columns combining conditions and actions"

  example:
    name: "Order Discount Rules"
    conditions:
      C1: "Customer Type"
      C2: "Order Amount"
      C3: "Payment Method"

    actions:
      A1: "Apply Discount %"
      A2: "Free Shipping"

    rules:
      R1:
        C1: "VIP"
        C2: "> $500"
        C3: "Any"
        A1: "20%"
        A2: "Yes"

      R2:
        C1: "Regular"
        C2: "> $100"
        C3: "Credit Card"
        A1: "10%"
        A2: "No"

      R3:
        C1: "Any"
        C2: "Any"
        C3: "Any"
        A1: "0%"
        A2: "No"
```

### Decision Table Template

```text
┌─────────────────────────────────────────────────────────────┐
│ Decision Table: {Name}                                      │
├─────────────────┬───────┬───────┬───────┬───────┬───────────┤
│ CONDITIONS      │  R1   │  R2   │  R3   │  R4   │  Default  │
├─────────────────┼───────┼───────┼───────┼───────┼───────────┤
│ {Condition 1}   │   Y   │   Y   │   N   │   N   │     -     │
│ {Condition 2}   │   Y   │   N   │   Y   │   N   │     -     │
├─────────────────┼───────┼───────┼───────┼───────┼───────────┤
│ ACTIONS         │       │       │       │       │           │
├─────────────────┼───────┼───────┼───────┼───────┼───────────┤
│ {Action 1}      │   X   │       │   X   │       │           │
│ {Action 2}      │       │   X   │   X   │       │     X     │
└─────────────────┴───────┴───────┴───────┴───────┴───────────┘
```

## Rule Documentation Templates

### Standard Rule Template

```yaml
rule_template:
  id: "BR-{domain}-{number}"
  name: "{descriptive name}"
  category: "constraint|derivation|inference|action|structural"
  statement: "{clear, unambiguous rule statement}"

  source:
    origin: "{stakeholder, document, regulation}"
    date: "{when identified}"
    authority: "{who can change this rule}"

  conditions:
    - "{condition 1}"
    - "{condition 2}"

  actions:
    - "{action if conditions met}"

  exceptions:
    - "{exception case}"

  examples:
    positive:
      - "{example where rule applies}"
    negative:
      - "{example where rule does not apply}"

  related_rules:
    - "{BR-xxx}"

  validation:
    testable: true
    test_approach: "{how to verify}"

  metadata:
    priority: "high|medium|low"
    volatility: "stable|volatile"
    enforcement: "automatic|manual"
```

### SBVR-Style Template

Semantics of Business Vocabulary and Business Rules (OMG standard):

```yaml
sbvr_template:
  vocabulary:
    term: "{term}"
    definition: "{meaning in business context}"

  structural_rule:
    format: "It is obligatory/permitted/forbidden that {statement}"
    example: "It is obligatory that each order has at least one line item"

  operative_rule:
    format: "If {condition} then {consequence}"
    example: "If order total exceeds $1000 then manager approval is required"
```

## Elicitation Techniques

### Rule Discovery Questions

```yaml
discovery_questions:
  constraints:
    - "What must always be true?"
    - "What must never happen?