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)

Rationalization	Why It's Wrong	Required Action
"I get the gist"	Gist-level understanding misses edge cases	Line-by-line analysis required
"This function is simple"	Simple functions compose into complex bugs	Apply 5 Whys anyway
"I'll remember this invariant"	You won't. Context degrades.	Write it down explicitly
"External call is probably fine"	External = adversarial until proven otherwise	Jump into code or model as hostile
"I can skip this helper"	Helpers contain assumptions that propagate	Trace the full call chain
"This is taking too long"	Rushed context = hallucinated vulnerabilities later	Slow is fast

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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