/sequential-think

name: sequential-think
description: |
  Multi-step reasoning engine for complex analysis and systematic problem solving. Use when: (1) Complex debugging scenarios with multiple layers, (2) Architectural analysis and system design, (3) Problems requiring hypothesis testing and validation, (4) Multi-component failure investigation, (5) Performance bottleneck identification. Triggers: "--think", "--think-hard", "--ultrathink", "analyze step by step", "break down this problem", "systematic analysis". IMPORTANT: Do NOT use for simple single-step tasks.

Sequential Think

Structured iterative thinking for complex problem-solving. Standalone CLI only (no MCP dependency).

Execution Methods

Run `scripts/sequential_think_cli.py` via Bash:

# Process a thought
python scripts/sequential_think_cli.py think \
  --thought "First, let me analyze the problem structure..." \
  --thought-number 1 \
  --total-thoughts 5

# Continue thinking chain
python scripts/sequential_think_cli.py think \
  --thought "Based on step 1, I hypothesize that..." \
  --thought-number 2 \
  --total-thoughts 5

# Revise a previous thought
python scripts/sequential_think_cli.py think \
  --thought "Reconsidering step 1, I realize..." \
  --thought-number 3 \
  --total-thoughts 5 \
  --is-revision \
  --revises-thought 1

# Branch into alternative path
python scripts/sequential_think_cli.py think \
  --thought "Alternative approach: what if we..." \
  --thought-number 4 \
  --total-thoughts 6 \
  --branch-from 2 \
  --branch-id "alt-approach"

# Final thought (complete chain)
python scripts/sequential_think_cli.py think \
  --thought "Conclusion: the solution is..." \
  --thought-number 5 \
  --total-thoughts 5 \
  --no-next

# View thought history
python scripts/sequential_think_cli.py history [--format json|text]

# Clear thought history
python scripts/sequential_think_cli.py clear

Core Principles

Iterative Thinking Process

• Each tool call = one "thought" in the chain
• Build upon, question, or revise previous thoughts
• Express uncertainty when it exists

Dynamic Thought Count

• Start with initial estimate of `totalThoughts`
• Adjust up/down as understanding evolves
• Add more thoughts even after reaching initial end

Hypothesis-Driven Approach

1. Generate hypotheses as potential solutions emerge 2. Verify hypotheses based on chain-of-thought steps 3. Repeat until satisfied with solution

Completion Criteria

• Only set `nextThoughtNeeded: false` when truly finished
• Must have satisfactory, verified answer
• Don't rush to conclusion

When to Use

| Scenario | Use Sequential Think | |----------|---------------------| | Complex debugging (3+ layers) | ✅ Yes | | Architectural analysis | ✅ Yes | | Multi-component investigation | ✅ Yes | | Performance bottleneck analysis | ✅ Yes | | Root cause analysis | ✅ Yes | | Simple explanation | ❌ No | | Single-file change | ❌ No | | Straightforward fix | ❌ No |

Parameters

| Parameter | Type | Required | Description | |-----------|------|----------|-------------| | `thought` | string | Yes | Current thinking step content | | `thoughtNumber` | int | Yes | Current position in sequence (1-based) | | `totalThoughts` | int | Yes | Estimated total thoughts needed | | `nextThoughtNeeded` | bool | No | Whether more thinking needed (default: true) | | `isRevision` | bool | No | Whether this revises previous thinking | | `revisesThought` | int | No | Which thought number is being reconsidered | | `branchFromThought` | int | No | Branching point thought number | | `branchId` | string | No | Identifier for current branch | | `needsMoreThoughts` | bool | No | Signal that more thoughts needed beyond estimate |

Output Format

{
  "thoughtNumber": 3,
  "totalThoughts": 5,
  "nextThoughtNeeded": true,
  "branches": ["alt-approach"],
  "thoughtHistoryLength": 3
}

Workflow Pattern

Phase 1: Problem Decomposition

Thought 1: Identify problem scope and constraints
Thought 2: Break into sub-problems
Thought 3: Identify dependencies between sub-problems

Phase 2: Hypothesis Generation

Thought 4: Generate initial hypothesis
Thought 5: Identify evidence needed to verify

Phase 3: Verification & Iteration

Thought 6: Test hypothesis against evidence
Thought 7: Revise if needed (isRevision=true)
Thought 8: Branch if alternative path promising

Phase 4: Conclusion

Final Thought: Synthesize findings, provide answer (nextThoughtNeeded=false)

Best Practices

1. **Start with estimate, adjust as needed**

• Initial `totalThoughts` is just a guess
• Increase if problem more complex than expected
• Decrease if solution found early

2. **Use revisions for course correction**

• Mark `isRevision=true` when reconsidering
• Reference `revisesThought` for clarity

3. **Branch for alternative approaches**

• Use `branchFromThought` to explore alternatives
• Give meaningful `branchId` names

4. **Filter irrelevant information**

• Each thought should advance toward solution
• Ignore tangential details

5. **Don't rush completion**

• Only `nextThoughtNeeded=false` when truly done
• Verify hypothesis before concluding

Anti-Patterns

| Prohibited | Correct | |------------|---------| | Use for simple tasks | Reserve for complex multi-step problems | | Skip thought numbers | Always increment correctly | | Conclude without verification | Verify hypothesis before final thought | | Ignore previous thoughts | Build upon or explicitly revise | | Fixed totalThoughts | Adjust as understanding evolves |

Integration with Other Tools

With ACE-Tool

ACE-Tool → align current state → Sequential Think → analyze and plan

With Context7

Sequential Think → coordinate analysis → Context7 → provide official patterns

With Serena

Serena → symbol-level exploration → Sequential Think → systematic analysis