| name | sequential-thinking |
| description | Structured reasoning tools for complex problem analysis with observation, hypothesis, analysis, and conclusion steps. Use when analyzing complex problems, debugging difficult issues, or making important decisions. |
| allowed-tools | Read, Write |
| mcp_tools | think_step, think_branch, think_summarize |
Sequential Thinking Skill
Version: 1.0.0
Purpose: Structured reasoning for complex problem analysis
Triggers
| Trigger |
Examples |
| Analyze |
"analyze problem", "think through", "問題分析" |
| Debug |
"debug this", "investigate issue", "調査" |
| Decide |
"help me decide", "evaluate options", "判断支援" |
| Reason |
"reason about", "think step by step", "段階的に考える" |
Integrated MCP Tools
| Tool |
Purpose |
think_step |
Record a reasoning step |
think_branch |
Create alternative thinking branch |
think_summarize |
Summarize thinking session |
Step Types
| Type |
Purpose |
Example |
observation |
Gather facts |
"The error occurs at startup" |
hypothesis |
Form theory |
"Configuration may be incorrect" |
analysis |
Evaluate |
"Testing hypothesis against logs" |
conclusion |
Final result |
"Root cause identified as X" |
question |
Open question |
"What is the expected behavior?" |
Workflow: Problem Analysis
Phase 1: Observation
Step 1.1: Gather Facts
Use think_step with:
- thought: "Observed: [specific observation]"
- type: "observation"
- confidence: 0.9 (high certainty)
Step 1.2: Document Context
Multiple think_step calls for each fact:
- System state
- Error messages
- Recent changes
- User reports
Phase 2: Hypothesis Formation
Step 2.1: Form Hypotheses
Use think_step with:
- thought: "Hypothesis: [potential cause]"
- type: "hypothesis"
- confidence: 0.5 (initial guess)
Step 2.2: Alternative Hypotheses
Use think_branch to explore:
- Different root causes
- Alternative explanations
- Edge cases
Phase 3: Analysis
Step 3.1: Test Hypotheses
Use think_step with:
- thought: "Testing: [method and result]"
- type: "analysis"
- confidence: [adjusted based on evidence]
Step 3.2: Eliminate Options
Use analysis steps to:
- Confirm or refute each hypothesis
- Document evidence
- Adjust confidence levels
Phase 4: Conclusion
Step 4.1: Draw Conclusions
Use think_step with:
- thought: "Conclusion: [final determination]"
- type: "conclusion"
- confidence: 0.9 (based on evidence)
Step 4.2: Summarize Session
Use think_summarize with:
- sessionId: Current session
- includeAlternatives: true
Branching Strategy
When to Branch
- Multiple valid hypotheses
- Need to explore alternatives
- Complex decision with trade-offs
Branch Usage
Use think_branch with:
- sessionId: Current session
- branchName: "alternative-approach"
- fromStep: Step number to branch from
Confidence Levels
| Level |
Value |
Meaning |
| Certain |
0.9-1.0 |
Strong evidence, verified |
| Likely |
0.7-0.9 |
Good evidence, probable |
| Possible |
0.5-0.7 |
Some evidence, uncertain |
| Unlikely |
0.3-0.5 |
Weak evidence |
| Doubtful |
0.0-0.3 |
Little to no evidence |
Example Session
1. [observation] Error: "Connection refused" on port 5432
2. [observation] PostgreSQL service status: stopped
3. [hypothesis] Database service crashed
4. [hypothesis] Port conflict with another service
5. [analysis] Checking service logs... no crash, clean shutdown
6. [analysis] Checking port usage... no conflict
7. [conclusion] Service was manually stopped, needs restart
Best Practices
✅ GOOD:
- Start with observations
- Form multiple hypotheses
- Document evidence for/against
- Update confidence as you learn
❌ BAD:
- Jump to conclusions
- Ignore contradicting evidence
- Single hypothesis bias
- Skip documentation
Checklist