Measure

---

name: measure description: Quantify values with uncertainty bounds. Use when estimating metrics, calculating risk scores, assessing magnitude, or measuring any quantifiable property. argument-hint: "[target] [metric] [unit]" disable-model-invocation: false user-invocable: true allowed-tools: Read, Grep, Bash context: fork agent: explore layer: UNDERSTAND

Intent

Quantify a specific metric for a target, providing a numerical value with explicit uncertainty bounds. This capability consolidates all estimation tasks (risk, impact, effort, etc.) into a single parameterized operation.

Success criteria:

• Numerical value provided for requested metric
• Uncertainty bounds explicitly stated
• Measurement method documented
• Units clearly specified

Compatible schemas:

• schemas/output_schema.yaml

Inputs

Parameter	Required	Type	Description
target	Yes	any	What to measure (system, code, entity, process)
metric	Yes	string	The metric to quantify (risk, complexity, effort, size, etc.)
unit	No	string	Unit of measurement (optional, inferred if not provided)
method	No	string	Measurement approach (heuristic, statistical, model-based)

Procedure

1. Define the metric: Clarify exactly what is being measured

   • Establish clear definition of the metric
   • Identify appropriate unit of measurement
   • Determine measurement methodology

2. Gather measurement inputs: Collect data needed for measurement

   • Read relevant files, logs, or data sources
   • Identify quantifiable indicators
   • Note data quality and completeness

3. Calculate measurement: Apply measurement method to inputs

   • Use appropriate calculation for the metric type
   • For risk: probability * impact assessment
   • For complexity: cyclomatic, cognitive, or structural metrics
   • For effort: decomposition and estimation techniques

4. Establish uncertainty bounds: Quantify measurement confidence

   • Calculate or estimate lower and upper bounds
   • Consider data quality, method limitations
   • Express as confidence interval or range

5. Ground the measurement: Document evidence and method

   • Reference specific data points used
   • Note any assumptions in calculation
   • Document measurement methodology

Output Contract

Return a structured object:

value: number  # The measured value
uncertainty:
  lower: number  # Lower bound (confidence interval)
  upper: number  # Upper bound (confidence interval)
  type: string  # Type of uncertainty (confidence_interval, range, std_dev)
unit: string  # Unit of measurement
metric: string  # What was measured
method: string  # How it was measured
breakdown:  # Optional component breakdown
  - component: string
    value: number
confidence: 0..1  # Confidence in measurement accuracy
evidence_anchors: ["file:line", "data:source"]
assumptions: []

Field Definitions

Field	Type	Description
value	number	Primary measurement value
uncertainty	object	Bounds and type of uncertainty
unit	string	Unit of measurement
metric	string	Name of measured property
method	string	Measurement methodology used
breakdown	array	Optional decomposition of measurement

Examples

Example 1: Measure Code Complexity

Input:

target: "src/services/order_processor.rb"
metric: "complexity"
unit: "cyclomatic"

Output:

value: 24
uncertainty:
  lower: 22
  upper: 26
  type: "range"
unit: "cyclomatic complexity"
metric: "complexity"
method: "counted decision points (if, case, loops, &&, ||)"
breakdown:
  - component: "process_order method"
    value: 12
  - component: "validate_items method"
    value: 8
  - component: "calculate_totals method"
    value: 4
confidence: 0.9
evidence_anchors:
  - "src/services/order_processor.rb:15-120"
assumptions:
  - "Ruby control flow statements counted as decision points"
  - "Exception handling counted as branches"

Example 2: Measure Risk

Input:

target: "database migration: add user_preferences column"
metric: "risk"
method: "probability_impact"

Output:

value: 0.35
uncertainty:
  lower: 0.25
  upper: 0.50
  type: "confidence_interval_90"
unit: "risk score (0-1)"
metric: "risk"
method: "probability (0.5) * impact (0.7) normalized"
breakdown:
  - component: "probability_of_failure"
    value: 0.5
  - component: "impact_if_failed"
    value: 0.7
  - component: "data_loss_risk"
    value: 0.2
  - component: "downtime_risk"
    value: 0.4
confidence: 0.7
evidence_anchors:
  - "migrations/20240115_add_preferences.rb:1-25"
  - "tool:grep:similar_migrations"
assumptions:
  - "Table has ~1M rows based on user count"
  - "Migration will lock table during ALTER"
  - "No concurrent deployments during migration"

Verification

• Numerical value provided
• Uncertainty bounds are reasonable (lower < value < upper)
• Unit of measurement specified
• Method documented
• Evidence anchors reference measurement inputs

Verification tools: Read (to verify measurement inputs)

Safety Constraints

• mutation: false
• requires_checkpoint: false
• requires_approval: false
• risk: low

Capability-specific rules:

• Always provide uncertainty bounds, never claim false precision
• Document measurement methodology for reproducibility
• Flag when data is insufficient for reliable measurement
• Do not extrapolate beyond available data without noting assumptions

Composition Patterns

Commonly follows:

• observe - Measure properties of observed state
• detect - Measure characteristics of detected items
• retrieve - Measure retrieved data

Commonly precedes:

• predict - Measurements feed into predictions
• compare - Measurements enable quantitative comparison
• plan - Measurements inform risk-aware planning

Anti-patterns:

• Never use measure for binary detection (use detect)
• Avoid measure for categorical assessment (use classify)

Workflow references:

• See reference/workflow_catalog.yaml#digital_twin_sync_loop for risk measurement