# ATLAS-GATE MCP Implementation Summary
**Complete implementation of governance, code enforcement, and audit system for production code quality.**
---
## What Was Implemented
### 1. Hard Block Policy (C2, C3, C5, C8 + Nulls)
**Absolutely forbidden, no exceptions, no plan override:**
- ❌ **C2 (Mock/Fake)** — Test doubles in production code
- ❌ **C3 (TODO/FIXME)** — Incomplete work markers
- ❌ **C5 (Policy Bypass)** — Always-allow, return true in auth
- ❌ **C8 (Simulated Outcome)** — SIMULATE, DRY_RUN flags that don't actually do work
- ❌ **Null Returns** — null, undefined, empty string returns
These patterns are detected in GATE 4 of write_file and cause immediate rejection with no possibility of override.
**Files**:
- `core/stub-detector.js` — Detection logic with HARD_BLOCK_PATTERNS
- `docs/HARD_BLOCK_POLICY.md` — Complete hard block policy documentation
---
### 2. Construct Taxonomy (C1-C8)
**Comprehensive audit specification for 15 programming languages:**
Languages covered:
- Java, Python, JavaScript/TypeScript, C#, C/C++
- Go, Rust, PHP, Ruby, Kotlin, Swift, Scala
- SQL, Bash, PowerShell
Each construct includes:
- Definition and risk classification
- Language-specific examples
- Detection signals
- True positive/false positive guidance
**Files**:
- `docs/CONSTRUCT_TAXONOMY.md` — Complete taxonomy (6000+ lines)
- `core/construct-detection-rules.json` — Machine-readable detection rules
- `docs/CONSTRUCT_AUDIT_GUIDE.md` — Developer audit reference
---
### 3. Code Enforcement Engine
**GATE 4 enforcement with multi-phase detection:**
Phase 1: **HARD BLOCKS** (immediate rejection)
- Scans for C2, C3, C5, C8, null/undefined returns
- No plan can override
Phase 2: **CRITICAL** (rejection)
- Scans for C1, C4, C6, C7
- All non-real constructs blocked
Phase 3: **AST Analysis** (JavaScript/TypeScript)
- Analyzes code structure
- Detects unconditional returns, empty functions, swallowed exceptions
**Files**:
- `core/stub-detector.js` — Enforcement logic
---
### 4. Plan Discovery System
**Supports multiple plan locations:**
Priority order:
1. `.atlas-gate/approved_plans/` (with underscore)
2. `.atlas-gate/plans/`
3. `.atlas-gate/approvedplans/` (no underscore)
4. `docs/plans/`
**Files updated**:
- `core/plan-enforcer.js` — Multi-location discovery
- `core/plan-registry.js` — Plan loading with fallbacks
- `tools/list_plans.js` — List all available plans
---
### 5. MCP Usage Documentation
**Complete guides for using the three core tools:**
#### read_prompt
- Unlocks write gates
- Required before any write_file call
- Usage: `await readPrompt({ name: "ANTIGRAVITY_CANONICAL" })`
#### read_file
- Read any file in the repository
- Understand existing code before writing
- Usage: `await readFile({ path: "src/auth.js" })`
#### write_file
- Create/modify files with full governance
- Requires approved plan
- Detects non-real constructs and blocks
- Runs preflight tests
- Records immutable audit log
- Usage: `await writeFile({ path, content, plan, role })`
**Files**:
- `docs/MCP_USAGE_GUIDE.md` — Complete step-by-step guide (700+ lines)
- `docs/MCP_QUICK_REFERENCE.md` — One-page reference card
- Real examples for each tool with correct and incorrect usage
---
### 6. Default Deny Policy
**All non-real constructs blocked by default:**
- C1 (Stub) — BLOCKED
- C2 (Mock/Fake) — HARD BLOCK
- C3 (TODO/FIXME) — HARD BLOCK
- C4 (Hardcoded Returns) — BLOCKED
- C5 (Policy Bypass) — HARD BLOCK
- C6 (Fake Approval) — BLOCKED
- C7 (Fake Limits) — BLOCKED
- C8 (Simulated Outcome) — HARD BLOCK
Only exception: Plans can authorize C1, C4, C6, C7 if documented. C2, C3, C5, C8 can NEVER be authorized.
**Files**:
- `core/construct-detection-rules.json` — Policy configuration
- `docs/HARD_BLOCK_POLICY.md` — No exceptions policy
---
## Key Design Decisions
### 1. Hard Block (C2, C3, C5, C8)
**Why permanent blocks?**
- **C5 (Policy Bypass)** — Security critical. If code says "return true", users can access anything.
- **C8 (Simulated Outcome)** — Data integrity. If code says "SIMULATE", orders get marked paid without charging.
- **C3 (TODO/FIXME)** — Incomplete code. TODOs become permanent technical debt.
- **C2 (Mock/Fake)** — Test doubles cause data loss and compliance violations.
**Why no plan override?**
- These aren't business decisions (which plans could authorize)
- These are fundamental integrity violations
- No amount of documentation makes them safe
### 2. Phase-Based Detection
```
GATE 4 Enforcement:
Phase 1: HARD BLOCKS (immediate rejection, no override)
└─ Throws immediately if found
Phase 2: CRITICAL patterns (C1, C4, C6, C7)
└─ Throws immediately if found
Phase 3: AST Analysis (null/undefined returns)
└─ Throws immediately if found
```
**Why separate phases?**
- Hard blocks are absolute (no negotiation)
- Critical patterns need same enforcement
- AST analysis provides deeper code structure validation
### 3. Default Deny
**All code assumed non-real until proven otherwise.**
- Every write scanned automatically
- Scanner looks for non-real patterns
- If found: BLOCKED
- If not found: Proceeds to other gates (role validation, preflight)
**Why?**
- Prevents accidental shipping of dev/test code
- Developers write real code intentionally, not accidentally
- Easier to review intent than to catch all bypass patterns
---
## Workflow Integration
### The 3-Step Workflow
```
STEP 1: PLAN
└─ Create or reference approved plan
└─ Plan must exist in .atlas-gate/approved_plans/ (or alternate location)
└─ Plan must have status: APPROVED
STEP 2: READ
└─ Understand existing code
└─ read_file(...) to view what's there
└─ read_prompt(...) to unlock write gates (required)
STEP 3: WRITE
└─ Create/modify file with governance
└─ Code is scanned for non-real constructs
└─ Hard blocks cause immediate rejection
└─ Preflight tests run
└─ Audit log recorded
```
### Error Flow
```
write_file(content, plan, ...)
↓
[Plan Validation] → Plan exists? Approved?
↓ (NO) → Error: PLAN_NOT_APPROVED
↓ (YES)
[GATE 4: Code Enforcement]
├─ Phase 1: Hard Blocks (C2, C3, C5, C8, nulls)
│ ↓ (FOUND) → Error: HARD_BLOCK_VIOLATION [NO OVERRIDE]
│ ↓ (NOT FOUND)
├─ Phase 2: Critical Patterns (C1, C4, C6, C7)
│ ↓ (FOUND) → Error: CONSTRUCT_TAXONOMY_VIOLATION
│ ↓ (NOT FOUND)
├─ Phase 3: AST Analysis
│ ↓ (FOUND) → Error: HARD_BLOCK_VIOLATION [nulls]
│ ↓ (NOT FOUND)
↓
[Role Validation] → Does metadata match code?
↓ (NO) → Error: ROLE_MISMATCH
↓ (YES)
[Preflight Tests] → Does code break the build?
↓ (YES) → Error: PREFLIGHT_FAILED [file reverted]
↓ (NO)
[Write to Filesystem]
↓
[Audit Log] → Record with full provenance
↓
Success: { status: "OK", plan, preflight: "PASSED" }
```
---
## Documentation Hierarchy
**3 levels of documentation:**
### Level 1: Quick Reference
- `docs/MCP_QUICK_REFERENCE.md` (1 page)
- The 3 tools, workflow, error fixes, best practices
- Start here if you know what you're doing
### Level 2: Complete Guide
- `docs/MCP_USAGE_GUIDE.md` (700+ lines)
- Step-by-step walkthrough
- Real examples for each tool
- Common errors and fixes
- Start here for first time
### Level 3: Reference Specifications
- `docs/CONSTRUCT_TAXONOMY.md` (6000+ lines)
- All 8 constructs, 15 languages, examples
- `docs/CONSTRUCT_AUDIT_GUIDE.md` (600+ lines)
- How to write legitimate code
- How to get plan authorization
- Detailed analysis of each construct
- `docs/HARD_BLOCK_POLICY.md` (300+ lines)
- Absolute rules
- No exceptions policy
- What to do instead
---
## Files Modified/Created
### Core Enforcement
- ✅ `core/stub-detector.js` — HARD_BLOCK_PATTERNS, 3-phase enforcement
- ✅ `core/plan-enforcer.js` — Multi-location plan discovery
- ✅ `core/plan-registry.js` — Fallback plan loading
- ✅ `tools/list_plans.js` — Plan discovery
### Documentation
- ✅ `docs/CONSTRUCT_TAXONOMY.md` — Complete 15-language taxonomy
- ✅ `docs/CONSTRUCT_AUDIT_GUIDE.md` — Developer guide
- ✅ `docs/CONSTRUCT_POLICY.md` — Policy document
- ✅ `docs/HARD_BLOCK_POLICY.md` — No exceptions rules
- ✅ `docs/MCP_USAGE_GUIDE.md` — Complete usage guide
- ✅ `docs/MCP_QUICK_REFERENCE.md` — One-page reference
### Configuration
- ✅ `core/construct-detection-rules.json` — Machine-readable rules
---
## Testing the Implementation
### Test Hard Blocks
```javascript
// These all cause immediate rejection with no override possible:
await writeFile({
path: "src/test.js",
content: "// TODO: implement", // ❌ C3 HARD BLOCK
plan: "PLAN_NAME"
});
await writeFile({
path: "src/test.js",
content: "return true;", // ❌ C5 HARD BLOCK
plan: "PLAN_NAME"
});
await writeFile({
path: "src/test.js",
content: "class FakePay { }", // ❌ C2 HARD BLOCK
plan: "PLAN_NAME"
});
```
### Test Real Code Passes
```javascript
// This should succeed:
await writeFile({
path: "src/auth/jwt-validator.js",
content: `
const jwt = require('jsonwebtoken');
async function validateToken(token) {
const decoded = jwt.verify(token, publicKey);
return decoded;
}
module.exports = { validateToken };
`,
plan: "PLAN_JWT_VALIDATION",
role: "EXECUTABLE"
});
// Response: { status: "OK", preflight: "PASSED" }
```
---
## Principles
### 1. Real Code Only
- No stubs, mocks, or placeholders
- No hardcoded test data
- No temporary hacks
### 2. Complete Code Only
- No TODOs or FIXMEs shipped
- All logic implemented
- No "will do later"
### 3. Auditable Code Only
- Every change tracked
- Plans documented
- No silent bypasses
### 4. Production-Ready Code Only
- Passes linting and tests
- No technical debt
- Real error handling
---
## What This Prevents
### Data Loss
- ✅ Prevents mocks/fakes that don't actually charge/transfer/persist
- ✅ No simulated outcomes that claim work was done
- ✅ No null returns that hide errors
### Security Breaches
- ✅ Prevents hardcoded "return true" in auth
- ✅ Prevents access control bypasses
- ✅ Prevents privilege escalation via fake policies
### Compliance Violations
- ✅ Prevents fake approval logic
- ✅ Prevents audit trail manipulation
- ✅ Prevents incomplete security controls
### Production Incidents
- ✅ Prevents shipped TODOs from breaking features
- ✅ Prevents hardcoded test data from going live
- ✅ Prevents silent failures via null returns
---
## Summary
**ATLAS-GATE MCP now provides:**
1. ✅ Hard block enforcement (C2, C3, C5, C8, nulls)
2. ✅ 15-language construct taxonomy
3. ✅ Plan-based governance
4. ✅ Immutable audit logging
5. ✅ Preflight testing
6. ✅ Complete documentation
7. ✅ Real code only guarantee
**Result**: Production code that is:
- **Real** — Actual implementations, not placeholders
- **Complete** — No incomplete markers
- **Auditable** — Full provenance tracking
- **Verified** — Passes all gates before shipping
