Sequential Thinking & UltraThink
Structured reasoning system for complex problem analysis and decision-making.
Activation Triggers
Use Sequential Thinking MCP when:
- •Breaking down complex problems into steps
- •Planning and design with room for revision
- •Architecture decisions affect 3+ files
- •Technology selection between multiple options
- •Performance vs maintainability trade-offs
- •Breaking changes under consideration
- •Multiple approaches exist to solve the same problem
- •Repetitive errors occur
Tool Parameters
Required Parameters:
- •
thought(string): Current thinking step content - •
nextThoughtNeeded(boolean): Whether another step is needed - •
thoughtNumber(integer): Current thought number (starts from 1) - •
totalThoughts(integer): Estimated total thoughts needed
Optional Parameters:
- •
isRevision(boolean): Whether this revises previous thinking - •
revisesThought(integer): Which thought is being reconsidered - •
branchFromThought(integer): Branching point for alternatives - •
branchId(string): Branch identifier - •
needsMoreThoughts(boolean): If more thoughts needed beyond estimate
Usage Pattern
Step 1 - Initial Analysis:
code
thought: "Analyzing the problem: [describe problem]" nextThoughtNeeded: true thoughtNumber: 1 totalThoughts: 5
Step 2 - Decomposition:
code
thought: "Breaking down: [sub-problems]" nextThoughtNeeded: true thoughtNumber: 2 totalThoughts: 5
Step 3 - Revision (if needed):
code
thought: "Revising thought 2: [correction]" isRevision: true revisesThought: 2 thoughtNumber: 3 totalThoughts: 5 nextThoughtNeeded: true
Final Step - Conclusion:
code
thought: "Conclusion: [final answer]" thoughtNumber: 5 totalThoughts: 5 nextThoughtNeeded: false
UltraThink Mode
Enhanced analysis mode activated by --ultrathink flag.
Activation:
code
"Implement authentication system --ultrathink" "Refactor the API layer --ultrathink"
Process:
- •Request Analysis: Identify core task, detect keywords, recognize complexity
- •Sequential Thinking: Begin structured reasoning
- •Execution Planning: Map subtasks to agents, identify parallel opportunities
- •Execution: Launch agents, integrate results
UltraThink Parameters:
Initial Analysis:
code
thought: "Analyzing user request: [content]" nextThoughtNeeded: true thoughtNumber: 1 totalThoughts: [estimate]
Subtask Decomposition:
code
thought: "Breaking down: 1) [task1] 2) [task2] 3) [task3]" nextThoughtNeeded: true thoughtNumber: 2
Agent Mapping:
code
thought: "Mapping: [task1] → expert-backend, [task2] → expert-frontend" nextThoughtNeeded: true thoughtNumber: 3
Execution Strategy:
code
thought: "Strategy: [tasks1,2] parallel, [task3] depends on [task1]" nextThoughtNeeded: true thoughtNumber: 4
Final Plan:
code
thought: "Plan: Launch [agents] in parallel, then [agent]" nextThoughtNeeded: false
When to Use
UltraThink is ideal for:
- •Complex multi-domain tasks (backend + frontend + testing)
- •Architecture decisions affecting multiple files
- •Performance optimization requiring analysis
- •Security review needs
- •Refactoring with behavior preservation
Benefits:
- •Structured decomposition of complex problems
- •Explicit agent-task mapping with justification
- •Identification of parallel execution opportunities
- •Context maintenance throughout reasoning
- •Revision capability when approaches need adjustment
Guidelines
- •Start with reasonable totalThoughts estimate
- •Use isRevision when correcting previous thoughts
- •Maintain thoughtNumber sequence
- •Set nextThoughtNeeded to false only when complete
- •Use branching for exploring alternatives