name: UltraCode Trace version: 1.0.0 description: Code tracing, debugging, "why not called", flow analysis, state dependencies triggers:

• debugging
• why not called
• flow analysis
• trace
• state dependencies

UltraCode Tracing — Claude Code Skill

Auto-activated for: Debugging, "why not called", flow analysis, state dependencies

Static analysis of code execution flow without running the code.

When to Use

trace_flow — Trace from A to B

Find all execution paths between two points:

trace_flow({
  from: "handleLogin",
  to: "redirectToHome",
  trackStates: true,     // Track state changes
  trackConditions: true, // Track branches
  maxDepth: 15,
  format: "mermaid"      // sequence | tree | graph | mermaid
})

Returns:

• Paths with confidence scores
• State changes at each step
• Conditions and branches
• Mermaid sequence diagram

trace_backwards — Why Not Called?

Understand why a method isn't being called:

trace_backwards({
  target: "FinishTask",
  question: "why_not_called", // | "what_affects" | "dependencies"
  depth: 15,
  includeStates: true
})

Question types:

• why_not_called — find blocking conditions
• what_affects — all dependencies
• dependencies — full dependency graph

Returns:

• List of callers with probability (always/conditional/rare)
• Blocking conditions with recommendations
• State dependencies
• Call chains
• Diagnosis with suggested debug points

trace_data_flow — Data Flow

Trace how data affects target state:

trace_data_flow({
  entryPoint: "AppInit",
  targetState: "startPage",
  dataSources: ["config", "api:fetchUser"], // auto-detect if empty
  trackTransformations: true
})

Data sources (auto-detect):

• API: fetch, axios, http
• Storage: localStorage, database
• Props: props, input, param
• State: state, store, redux
• Config: config, settings, env

Returns:

• Data flows from sources
• Transformations (parse, map, validate)
• Branches based on data
• Behavior matrix for different inputs

analyze_state_impact — State Impact

Understand how state affects different scenarios:

analyze_state_impact({
  state: "user.isAuthenticated",
  scenarios: [
    { value: true, label: "logged in" },
    { value: false, label: "logged out" }
  ]
})

Returns:

• All state usages (read/write/condition)
• For each scenario:
  • Available paths
  • Blocked paths
  • Enabled features
• Conflicts (multiple writers, race conditions)
• Ripple effects (direct and indirect)

find_decision_points — Decision Points

Find all places where code makes decisions:

find_decision_points({
  scenario: "checkout flow",
  includeGuards: true,
  includeEffects: true,
  groupBy: "impact" // | "location" | "type"
})

Decision point types:

• validation — input validation
• api_response — API response handling
• state_mutation — state changes
• guard — guard conditions (early return)
• loop — loop control
• error_handling — try-catch
• feature_flag — feature toggles

Impact levels:

• critical — blocks execution
• high — significant impact
• medium — moderate impact
• low — minimal impact

Returns:

• Decision points with classification
• Mermaid flowchart
• Summary: total, critical, possible outcomes

Usage Examples

Debugging: Why Doesn't It Fire?

// Step 1: Find blocking conditions
trace_backwards({
  target: "sendNotification",
  question: "why_not_called"
})
// → Finds: "user.preferences.notifications === false" blocks

// Step 2: Check setting impact
analyze_state_impact({
  state: "user.preferences.notifications",
  scenarios: [
    { value: true, label: "enabled" },
    { value: false, label: "disabled" }
  ]
})
// → Shows which paths are open/closed for each value

Understanding: How Does Data Affect UI?

trace_data_flow({
  entryPoint: "loadDashboard",
  targetState: "dashboardData"
})
// → Shows: API → parse → validate → setState
// → Matrix: if API error → fallback state

Refactoring: Where to Change Logic?

find_decision_points({
  scenario: "user authentication",
  groupBy: "impact"
})
// → List of all if/switch/guards related to auth
// → Grouped by importance

Output Formats

Text (default)

═══ Trace Flow: handleLogin → redirectToHome ═══

Found 2 path(s):

─── Path 1 (confidence: 85%) ───
Summary: Login flow via session creation

  1. → handleLogin (/src/auth.ts:10)
     └─ if: credentials.valid
  2. → createSession (/src/session.ts:5)
     └─ isAuthenticated: false → true
  3. → redirectToHome (/src/router.ts:100)

─── States ───
Modified: isAuthenticated, currentSession

Mermaid

sequenceDiagram
  participant P0 as handleLogin
  participant P1 as createSession
  participant P2 as redirectToHome
  P0->>P1: credentials.valid
  P1->>P2: session created

Semantic Integration

Tracing automatically uses semantic search (if available) for:

• Fuzzy search of entry/exit points by description
• Improved analysis quality
• Natural language queries

trace_flow({
  from: "user login handler",  // Semantic search finds handleLogin
  to: "home page redirect"     // Finds redirectToHome
})

Tool Reference

trace_flow

trace_backwards

trace_data_flow

analyze_state_impact

find_decision_points

Related Skills

• ultracode — Code analysis, semantic search, refactoring, code modification
• ultracode-autodoc — Working with .autodoc/ directory