> ## Documentation Index
> Fetch the complete documentation index at: https://mcp-server-langgraph.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# v2.3.0 - Type Safety

> Compliance storage backend, Pydantic V2 migration, and enhanced type safety

<Note type="info">
  **Release Date**: 2025-10-13
  **Breaking Changes**: None (Pydantic V2 backward compatible)
</Note>

### Overview

Version 2.3.0 completes the compliance storage backend infrastructure, migrates to Pydantic V2, and significantly enhances type safety across the codebase.

### Key Features

#### 🗄️ Compliance Storage Backend

Complete pluggable storage architecture with 5 abstract interfaces and in-memory implementations.

**New Interfaces** (`src/mcp_server_langgraph/core/compliance/storage.py` - 735 lines):

* `UserProfileStore` - CRUD operations for user profiles
* `ConversationStore` - Manage conversations with archival
* `PreferencesStore` - User preferences key-value storage
* `AuditLogStore` - Audit logging with date filtering
* `ConsentStore` - GDPR consent tracking

**In-Memory Implementations**:

* For development and testing without external dependencies
* Production-ready interface for database backends

**Benefits**:

* Pluggable architecture
* Type safety with Pydantic models
* GDPR compliant

#### 🔒 Enhanced Type Safety

**Coverage Increase**: 27% → 64%

**Strict mypy typing** enabled for additional modules:

* `mcp_server_langgraph.auth.*`
* `mcp_server_langgraph.llm.*`
* `mcp_server_langgraph.core.agent`

**Settings**: `disallow_untyped_calls = true`, `strict = true`

**Impact**: Catches type errors at development time, prevents runtime bugs

#### 📋 Pydantic V2 Migration

**Fixed Deprecations**:

* Replaced `class Config` with `model_config = ConfigDict(...)`
* Replaced deprecated `regex` parameter with `pattern` in Query validators

**Files Updated**:

* `data_export.py`: UserDataExport model
* `gdpr.py`: UserProfileUpdate, ConsentRecord, ConsentResponse models

**Impact**: Eliminates 5 Pydantic deprecation warnings, future-proofs for Pydantic V3

#### 📚 Error Handling Strategy Documentation

Created `docs/architecture/adr-0006-error-handling-strategy` (600+ lines):

* 5 error categories (Client 4xx, Server 5xx)
* Layered propagation pattern (4 layers)
* Consistent JSON response format
* Retry strategies (LLM: 3x, OpenFGA: 2x, Redis: 2x)
* 40+ standardized error codes
* OpenTelemetry integration

### Files Modified

<AccordionGroup>
  <Accordion title="Compliance Module (4 files)" icon="database">
    1. **storage.py** (NEW) - 735 lines
       * 5 abstract interfaces
       * 6 Pydantic models
       * 5 in-memory implementations

    2. **data\_export.py** (MODIFIED)
       * Integrated with UserProfileStore
       * Integrated with ConversationStore, PreferencesStore
       * Pydantic V2 migration

    3. **retention.py** (MODIFIED)
       * Cleanup inactive sessions integration

    4. **session.py** (MODIFIED)
       * Added get\_inactive\_sessions()
       * Added delete\_inactive\_sessions()
  </Accordion>

  <Accordion title="Configuration (2 files)" icon="gear">
    5. **pyproject.toml**
       * Strict mypy for auth/llm/agent modules

    6. **.flake8** (NEW)
       * Explicit configuration (47 lines)
       * Max line length: 127 (aligned with Black)
       * Google docstring convention
  </Accordion>
</AccordionGroup>

### Dependency Management

#### New Documentation

* `docs/DEPENDENCY_MANAGEMENT.md` (580 lines)
* `scripts/dependency-audit.sh` (320 lines)

**4-Phase Update Strategy**:

* Critical security: 48h SLA
* Major versions: 2-4 weeks
* Minor versions: 1-2 weeks
* Patches: 1 month

**Monthly Audit Script**:

* Outdated packages scan
* Security vulnerability scan (pip-audit)
* License compliance (pip-licenses)
* Dependency conflict detection

### Upgrade Guide

#### From v2.2.0

```bash theme={null}
## 1. Update dependencies
git pull origin main
uv sync

## 2. Verify Pydantic V2
python -c "import pydantic; print(pydantic.__version__)"
## Expected: 2.x

## 3. Run type checks
mypy src/
## Should pass with new strict typing

## 4. Test compliance storage
pytest tests/test_storage.py -v
```

#### For Custom Extensions

If you've extended Pydantic models:

```python theme={null}
## Before (v1.x)
class MyModel(BaseModel):
    class Config:
        arbitrary_types_allowed = True

## After (v2.x)
from pydantic import ConfigDict

class MyModel(BaseModel):
    model_config = ConfigDict(arbitrary_types_allowed=True)
```

### What's Next

#### v2.4.0

* LangGraph 0.6.10 upgrade
* 100% test pass rate
* 21 comprehensive ADRs