Ultrathink Trigger

Automatically invoke maximum reasoning depth for complex problems.

Complexity Indicators

Signal	Weight	Example
Files affected > 5	+2	Refactoring across modules
Unfamiliar language/framework	+3	First time with codebase
Architecture decision	+4	Choosing patterns
2+ failed fix attempts	+3	Root cause unclear
Multi-domain interaction	+2	Frontend + Backend + DB
Security implications	+3	Auth, permissions, secrets
Performance-critical code	+2	Hot paths, algorithms
Breaking change potential	+3	API changes, schema migrations

Threshold

If total weight >= 5: Trigger ultrathink mode

Invocation

Prefix complex analysis with one of:

• "Think harder about this:"
• "ultrathink:"
• "Take your time to deeply analyze:"

These phrases trigger Claude's extended thinking mode for more thorough analysis.

Integration Points

With /fix command

After 2 failed attempts, automatically invoke:

ultrathink: What are all the possible root causes?
What assumptions am I making? What haven't I checked yet?

With /brainstorm command

Auto-triggers when topic complexity >= 5 (or

--deep

flag). Applied to EVALUATE and SYNTHESIZE phases:

ultrathink: Deeply analyze these options considering trade-offs,
edge cases, maintainability, and long-term implications.

Flags:

• --deep

  - Force ultrathink regardless of complexity

• --quick

  - Suppress auto-detect, stay fast

With orchestrator INNOVATE phase

For architecture decisions:

ultrathink: Evaluate these approaches considering
maintainability, performance, security, and complexity.

With sequential-thinking

For multi-step complex analysis:

mcp__sequential_thinking__sequentialthinking({
  thought: "ultrathink: [complex problem]",
  thoughtNumber: 1,
  totalThoughts: 10, // More steps for deep analysis
  nextThoughtNeeded: true
})

When to Use Proactively

1. Architecture Decisions: Before proposing patterns or structure
2. Debugging Deadlock: After 2+ failed fix attempts
3. Security Analysis: Any auth, permission, or secret handling
4. Performance Optimization: Before optimizing hot paths
5. Breaking Changes: Before proposing API/schema changes
6. Unfamiliar Code: First encounter with a new codebase area

Example Workflow

1. Encounter complex problem
2. Calculate complexity weight:
   - Multi-file change: +2
   - Architecture decision: +4
   - Total: 6 (>= 5, triggers ultrathink)
3. Invoke: "ultrathink: Design the data flow for..."
4. Extended analysis produces thorough solution
5. Proceed with implementation

Anti-Patterns

• Using ultrathink for simple, well-understood tasks
• Skipping ultrathink for complex problems to "save time"
• Not recalculating complexity when scope changes