Analyze fundamental data primitives, type systems, and state management patterns in a codebase. Use when (1) evaluating typing strategies (Pydantic vs TypedDict vs loose dicts), (2) assessing immutability and mutation patterns, (3) understanding serialization approaches, (4) documenting state shape and lifecycle, or (5) comparing data modeling approaches across frameworks.
Analyzes the fundamental units of data and state management patterns.
| Strategy | Indicators | Files to Check |
|---|---|---|
| Pydantic | BaseModel, Field(), validator | models.py, schema.py |
| Dataclass | @dataclass, field() | types.py, models.py |
| TypedDict | TypedDict, Required[], NotRequired[] | types.py |
| NamedTuple | NamedTuple, typing.NamedTuple | types.py |
| Loose | Dict[str, Any], plain dict | Throughout |
# In-place list modification
state.messages.append(msg)
state.history.extend(new_items)
# Direct dict mutation
state['key'] = value
state.update(new_data)
# Object attribute mutation
state.status = 'complete'
# Pydantic copy
new_state = state.model_copy(update={'key': value})
# Dataclass replace
new_state = replace(state, messages=[*state.messages, msg])
# Spread operator style
new_state = {**state, 'key': value}
# Frozen dataclass
@dataclass(frozen=True)
class State: ...
| Method | Code Pattern | Trade-offs |
|---|---|---|
| Pydantic JSON | .model_dump_json() | Type-safe, automatic |
| Pydantic Dict | .model_dump() | For internal use |
| Dataclass | asdict(obj) | Manual, no validation |
| Custom | to_dict(), from_dict() | Full control |
| Pickle | pickle.dumps() | Fast, fragile, security risk |
| JSON | json.dumps(obj, default=...) | Requires encoder |
## Data Substrate Analysis: [Framework Name]
### Typing Strategy
- **Primary Approach**: [Pydantic/Dataclass/TypedDict/Loose]
- **Key Files**: [List of files]
- **Nesting Depth**: [Shallow/Medium/Deep]
- **Validation**: [At boundaries/Everywhere/None]
### Core Primitives
| Type | Location | Purpose | Mutability |
|------|----------|---------|------------|
| Message | schema.py:L15 | Chat message | Immutable |
| State | state.py:L42 | Agent state | Mutable ⚠️ |
| Result | types.py:L78 | Tool output | Immutable |
### Mutation Analysis
- **Pattern**: [In-place/Copy-on-write/Mixed]
- **Risk Areas**: [List of mutable state locations]
- **Concurrency Safe**: [Yes/No/Partial]
### Serialization
- **Method**: [Pydantic/Custom/JSON]
- **Implicit/Explicit**: [Description]
- **Round-trip Tested**: [Yes/No/Unknown]
codebase-mapping to identify type filescomparative-matrix for typing decisionsresilience-analysis for error handling in serialization