sequential-thinking

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Structured reasoning framework for complex multi-step analysis using MCP sequential thinking tool. Provides state-based reasoning, branch/revise decision thresholds, quality scoring, and convergence rules for problems requiring 3+ logical steps, debugging unclear root causes, or handling multiple valid approaches.

⭐4stars🔀0forks📁View on GitHub🕐Updated Dec 22, 2025
[Debugging]

When & Why to Use This Skill

This Claude skill implements a structured reasoning framework using the MCP sequential thinking tool, specifically designed for complex multi-step analysis. It enables agents to perform state-based reasoning, branch into alternative hypotheses, and revise logic based on new evidence. By applying rigorous quality scoring and convergence rules, it ensures high-accuracy problem-solving for tasks that involve unclear root causes or require navigating multiple valid approaches.

Use Cases

  • Root Cause Analysis: Systematically debugging intricate software bugs or system failures by tracing causal chains and verifying state transitions.
  • Complex Technical Planning: Breaking down multi-layered engineering problems into a sequence of verified logical steps and preconditions.
  • Strategic Hypothesis Testing: Exploring and evaluating multiple valid approaches to a problem through branching and iterative revision to find the optimal solution.
  • Logical Validation: Enhancing the reliability of complex reasoning tasks by applying quality scoring to detect circular logic, invalid transitions, or unverified assumptions.
namesequential-thinking
descriptionStructured reasoning framework for complex multi-step analysis using MCP sequential thinking tool. Provides state-based reasoning, branch/revise decision thresholds, quality scoring, and convergence rules for problems requiring 3+ logical steps, debugging unclear root causes, or handling multiple valid approaches.
allowed-toolsRead, Write, Bash (*), mcp__sequential-thinking__sequentialthinking

Sequential Thinking Methodology

Framework for using /mcp__sequential-thinking__sequentialthinking tool effectively.

Quick Assessment

Skip entirely for: Simple facts, obvious fixes, single-step answers, routine tasks

Apply when:

  • Problem requires 3+ logical steps
  • Multiple valid approaches exist
  • Debugging with unclear root causes
  • Initial confidence <70%
  • State transitions or causal chains involved

Core Framework

1. Initial Classification

Simple → Skip tool
Medium → 3-4 thoughts  
Complex → up to 7 thoughts

Define: initial state → goal state → success criteria

2. State-Based Reasoning

For each thought:

  1. Current state: What's true now?
  2. Preconditions: What must be true for next action?
  3. Effects: How does action change state?
  4. Verify: Valid and closer to goal?
  5. Check: Success criteria met?

3. Thought Structure

Thought N: [Hypothesis/Analysis/Action]
- State: [explicit]
- Logic: [deduction|induction|abduction|causal]  
- Confidence: X%
- Next: [what this enables]

4. Decision Points

Branch (branch_from_thought + unique branch_id):

  • Confidence <60% WITH alternative
  • Contradiction found
  • Equal validity paths (Δ<10%)

Revise (is_revision=true + revises_thought):

  • Fundamental error
  • Precondition false
  • Better approach (>20% gain)

Extend (needs_more_thoughts=true):

  • Approaching limit but incomplete

5. Quality Scoring

Start: 0 | Minimum: 5 points

Positive: Clear mechanism (+2), Verified assumption (+2), Resolved contradiction (+2), Valid transition (+1)

Negative: Circular reasoning (-3), Invalid transition (-3), Unverified assumption (-2), Logical leap (-1)

If <5 after 3 thoughts → reassess approach

6. Convergence Rules

  • Thoughts 1-2: Explore breadth (20%)
  • Thoughts 3-5: Deep dive (60%)
  • Thoughts 6-7: Verify only (20%)

Terminate when: 7 thoughts reached | Confidence >90% for 2 consecutive | Cycling detected | Success met

Code-Specific Additions

Track: Variable states, Pre/postconditions, Resource constraints, Error paths

Verify: Execution traces, Edge cases, Resource cleanup, Thread safety

Natural Language Integration

Use markers like:

  • "Let me work through this systematically..."
  • "This leads me to consider..."
  • "A potential issue here is..."

Never expose: Internal scores, Framework mechanics, Artificial confidence percentages

Meta-Rules

  • Admit uncertainty rather than guess
  • Each thought must advance solution
  • No pure repetition
  • Don't fake confidence to avoid branching