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:
thought: "Analyzing the problem: [describe problem]" nextThoughtNeeded: true thoughtNumber: 1 totalThoughts: 5
Step 2 - Decomposition:
thought: "Breaking down: [sub-problems]" nextThoughtNeeded: true thoughtNumber: 2 totalThoughts: 5
Step 3 - Revision (if needed):
thought: "Revising thought 2: [correction]" isRevision: true revisesThought: 2 thoughtNumber: 3 totalThoughts: 5 nextThoughtNeeded: true
Final Step - Conclusion:
thought: "Conclusion: [final answer]" thoughtNumber: 5 totalThoughts: 5 nextThoughtNeeded: false
UltraThink Mode
Enhanced analysis mode activated by --ultrathink flag.
Activation:
"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:
thought: "Analyzing user request: [content]" nextThoughtNeeded: true thoughtNumber: 1 totalThoughts: [estimate]
Subtask Decomposition:
thought: "Breaking down: 1) [task1] 2) [task2] 3) [task3]" nextThoughtNeeded: true thoughtNumber: 2
Agent Mapping:
thought: "Mapping: [task1] → expert-backend, [task2] → expert-frontend" nextThoughtNeeded: true thoughtNumber: 3
Execution Strategy:
thought: "Strategy: [tasks1,2] parallel, [task3] depends on [task1]" nextThoughtNeeded: true thoughtNumber: 4
Final Plan:
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