Deep Context Builder Skill (Ultra-Granular Pure Context Mode)

1. Purpose

This skill governs how Claude thinks during the context-building phase of an audit.

When active, Claude will:

• Perform line-by-line / block-by-block code analysis by default.
• Apply First Principles, 5 Whys, and 5 Hows at micro scale.
• Continuously link insights → functions → modules → entire system.
• Maintain a stable, explicit mental model that evolves with new evidence.
• Identify invariants, assumptions, flows, and reasoning hazards.

This skill defines a structured analysis format (see Example: Function Micro-Analysis below) and runs before the vulnerability-hunting phase.

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When to Use

Use when:

• Deep comprehension is needed before bug or vulnerability discovery.
• You want bottom-up understanding instead of high-level guessing.
• Reducing hallucinations, contradictions, and context loss is critical.
• Preparing for security auditing, architecture review, or threat modeling.

Do not use for:

• Vulnerability findings
• Fix recommendations
• Exploit reasoning
• Severity/impact rating

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2. How This Skill Behaves

When active, Claude will:

• Default to ultra-granular analysis of each block and line.
• Apply micro-level First Principles, 5 Whys, and 5 Hows.
• Build and refine a persistent global mental model.
• Update earlier assumptions when contradicted ("Earlier I thought X; now Y.").
• Periodically anchor summaries to maintain stable context.
• Avoid speculation; express uncertainty explicitly when needed.

Goal: deep, accurate understanding, not conclusions.

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Rationalizations (Do Not Skip)

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3. Phase 1 — Initial Orientation (Bottom-Up Scan)

Before deep analysis, Claude performs a minimal mapping:

1. Identify major modules/files/contracts.
2. Note obvious public/external entrypoints.
3. Identify likely actors (users, owners, relayers, oracles, other contracts).
4. Identify important storage variables, dicts, state structs, or cells.
5. Build a preliminary structure without assuming behavior.

This establishes anchors for detailed analysis.

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4. Phase 2 — Ultra-Granular Function Analysis (Default Mode)

Every non-trivial function receives full micro analysis.

5.1 Per-Function Microstructure Checklist

For each function:

1. Purpose

   • Why the function exists and its role in the system.

2. Inputs & Assumptions

   • Parameters and implicit inputs (state, sender, env).
   • Preconditions and constraints.

3. Outputs & Effects

   • Return values.
   • State/storage writes.
   • Events/messages.
   • External interactions.

4. Block-by-Block / Line-by-Line Analysis For each logical block:

   • What it does.
   • Why it appears here (ordering logic).
   • What assumptions it relies on.
   • What invariants it establishes or maintains.
   • What later logic depends on it.

   Apply per-block:

   • First Principles
   • 5 Whys
   • 5 Hows

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5.2 Cross-Function & External Flow Analysis

(Full Integration of Jump-Into-External-Code Rule)

When encountering calls, continue the same micro-first analysis across boundaries.

Internal Calls

• Jump into the callee immediately.
• Perform block-by-block analysis of relevant code.
• Track flow of data, assumptions, and invariants: caller → callee → return → caller.
• Note if callee logic behaves differently in this specific call context.

External Calls — Two Cases

Case A — External Call to a Contract Whose Code Exists in the Codebase Treat as an internal call:

• Jump into the target contract/function.
• Continue block-by-block micro-analysis.
• Propagate invariants and assumptions seamlessly.
• Consider edge cases based on the actual code, not a black-box guess.

Case B — External Call Without Available Code (True External / Black Box) Analyze as adversarial:

• Describe payload/value/gas or parameters sent.
• Identify assumptions about the target.
• Consider all outcomes:
  • revert
  • incorrect/strange return values
  • unexpected state changes
  • misbehavior
  • reentrancy (if applicable)

Continuity Rule

Treat the entire call chain as one continuous execution flow. Never reset context. All invariants, assumptions, and