S-Class: Universal Trust & Control Plane

Version: v6.0.1 Canonical Production
Status: Full Production Hardening Complete — S0 through S5 + K1–K12 Crash Durability + IDE MCP Plugin Live
Normative Contract: 00-SPEC/S-CLASS-v6.0.1-FINAL-FIXED-DESIGN.md

S-Class is the universal trust and control plane between autonomous AI coding agents and developer workspaces. Operating as a Senior Staff SDE Co-Pilot and IDE governance plugin, it guarantees that no AI model or user action can alter workspace state without verifiable authority, bounded execution leases, deterministic observation, independent multi-engine verification, and canonical event reduction.

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Branch Taxonomy & Repository Map

To avoid confusion when navigating the repository, branches are strictly divided into Active Production Lines and Historical Archives:

gitGraph
   commit id: "legacy-v5"
   branch archive/v5-pre-canonical
   commit id: "v5-archive-head"
   checkout main
   branch research
   commit id: "research-head"
   checkout main
   branch working-pre-d0
   commit id: "pre-d0-head"
   checkout main
   branch survival-v0
   commit id: "survival-head"
   checkout main
   commit id: "787e8a1 (v6.0.1-canonical)"
   commit id: "P0-Security-Enclosure"
   commit id: "K1-K12-Durability"
   commit id: "Intelligence-Compiler"
   commit id: "MCP-IDE-Plugin (HEAD)"

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1. Active Production Branches

• main (Primary / Default):
  The authoritative production line for S-Class v6.0.1. Houses the complete runtime, fail-closed ExecutionGate, K1–K12 crash consistency engine, multi-engine verification plane, and the stdio MCP server for IDEs. All 210 automated tests pass cleanly here.
• v6.0.1-canonical:
  The upstream-synchronized canonical reference branch tracking the frozen v6.0.1 specification line.

2. Historical & Archived Branches (Do Not Delete)

• archive/v5-pre-canonical:
  Safety archive backing up the entire pre-v6 legacy main branch before the v6.0.1 canonical promotion. Preserves all past commit history and documentation.
• survival-v0:
  Historical branch containing the early v5 survival-mode architecture prototype.
• working-pre-d0:
  Historical branch containing early development prior to the D0 canonical event store milestones.
• research:
  Historical exploratory research branch.
• audit/truth-and-authority-gate:
  Local audit checkpoint from the September 25 DEFECT-07 compliance evaluation.

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Architecture Overview

S-Class replaces fragmented heuristics with a mathematically rigorous, fail-closed state machine architecture:

IDE User / Plain English Prompt
    ↓
Intent-to-Engineering Compiler (04-INTELLIGENCE)
    ↓
Engineering World Model & ContextPackage Guardrails
    ↓
ActionRequest / WorkProposal
    ↓
Authority / Policy Conjunction
    ↓
Admission & Capability Token (14-Step Gate)
    ↓
Descriptor-Relative Snapshot Boundary & Quiescence Proof
    ↓
Runtime Execution (Subprocess / Patch Agent)
    ↓
Independent Observation Diff & Receipt Capture
    ↓
Multi-Engine Verifier (Pytest, Hypothesis, Ruff)
    ↓
Signed Evidence Closure
    ↓
Canonical Reducer & SQLite EventStore (WAL + FULL)
    ↓
Replay-Equivalence & Release Evaluation (ReleaseVerdict.READY)

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Repository Structure

The canonical v6.0.1 repository is organized into strict, decoupled layers:

.
├── 00-SPEC/
│   └── S-CLASS-v6.0.1-FINAL-FIXED-DESIGN.md   # Active normative contract and formal specification
├── 10-CONFORMANCE/
│   ├── sclass_semantics_v6_0_1.py            # Canonical semantic kernel (260 types, 56 events, C1)
│   ├── test_sclass_v6_0_1_conformance.py      # Conformance & 24 adversarial gates
│   ├── test_sclass_v6_0_1_property.py         # Hypothesis property verification matrices
│   ├── c1-vectors.v6.0.1.json                 # C1 canonicalization test vectors
│   └── state-machines.v6.0.1.json             # Canonical state transition definitions
├── 20-RUNTIME/
│   ├── sclass_runtime_v6_0_1.py               # ExecutionGate, LinuxExecutionBoundary, ControlPlane
│   └── test_sclass_runtime_v6_0_1.py          # End-to-end runtime & verification lifecycle tests
├── src/sclass/
│   ├── __init__.py                            # Package facade
│   ├── client.py                              # SClassClient SDK (autonomous operating cycle)
│   ├── intelligence/                          # IntentCompiler & EngineeringWorldModelBuilder
│   ├── verification/                          # MultiEngineVerificationPlane (pytest, hypothesis, ruff)
│   └── workers/                               # WorkerHarness, SubprocessToolWorker, PatchAgentWorker
├── tests/
│   ├── adversarial/                           # ZV1–ZV10 Zero-Violation property tests
│   ├── benchmarks/                            # SLA & scale performance contract tests
│   ├── e2e/                                   # Golden vertical slice end-to-end tests
│   ├── errata/                                # ERR-001 through ERR-010 regression tests
│   ├── intelligence/                          # Intent compiler & world model tests
│   ├── interfaces/                            # MCP stdio JSON-RPC server tests
│   ├── stage_exit/                            # S1–S5 & K1–K12 crash consistency exit tests
│   ├── verification/                          # Verification engine & injection sanitization tests
│   └── workers/                               # Worker harness security & fail-closed tests
├── tools/
│   ├── cli/sclass.py                          # High-level CLI commands (sclass run, verify, release)
│   ├── mcp/sclass_mcp_server.py               # Production stdio MCP Server (JSON-RPC 2.0)
│   ├── promote_canonical.py                   # Canonical promotion tool
│   ├── run_all_s0_partitions.py               # S0 5-partition mutation runner
│   └── run_cr.py                              # Cosmic Ray mutation testing wrapper
├── pyproject.toml                             # Package build definition & test configuration
├── cosmic-ray.toml                            # Cosmic Ray mutation configuration
└── S0_CLOSURE_REPORT.md                       # Executable S0 certification evidence

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Verification & Test Execution

1. Run Complete Automated Test Suite (210 Tests)

python -m pytest tests/ 10-CONFORMANCE/ 20-RUNTIME/

Result: 210 passed, 3 skipped (Linux OS shims on Windows).

2. Verify Adversarial & Durability Properties

# ZV1 through ZV10 Zero-Violation Gates
python -m pytest tests/adversarial/

# K1 through K12 Full Crash Consistency Matrix
python -m pytest tests/stage_exit/test_s4_exit.py

3. Verify Spec Integrity & Linting

python 10-CONFORMANCE/spec_integrity.py
python -m ruff check src tests tools

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IDE Integration via MCP Server

To use S-Class as an autonomous Senior Staff co-pilot in VS Code, Cursor, Windsurf, or Antigravity, register the stdio server in your editor's MCP configuration (mcpServers):

{
  "mcpServers": {
    "sclass": {
      "command": "python",
      "args": ["tools/mcp/sclass_mcp_server.py"],
      "env": {
        "PYTHONPATH": "."
      }
    }
  }
}

Available Tools:

1. sclass_guide_task(intent: str): Indexes repository symbols and returns structured architectural guardrails, constraints, and test obligations for the IDE model.
2. sclass_validate_patch(patch: str, target_file: str): Runs the proposed diff through the sandboxed 14-step ExecutionGate and multi-engine verifiers before admitting changes.
3. sclass_get_status(): Inspects active obligations, budget allocations, and release readiness.

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License

Apache-2.0