# Implementation Plan: [Feature Title]

**Generated:** [auto-generated date]
**Spec:** `[path to spec.yaml]`
**Ticket Type:** Feature
**Estimated Effort:** [time estimate]

---

## Executive Summary

[1-2 paragraph overview of what's being built and the high-level approach]

**Key Deliverables:**
- [Deliverable 1]
- [Deliverable 2]
- [Deliverable 3]

---

## Technical Decisions

### Decision 1: [Decision Title]
**Choice:** [What was decided]
**Rationale:** [Why this choice]
**Alternatives Considered:** [Other options and why not chosen]

### Decision 2: [Decision Title]
**Choice:** [What was decided]
**Rationale:** [Why this choice]
**Alternatives Considered:** [Other options and why not chosen]

[Continue for all major decisions...]

---

## File Structure

### New Files to Create

1. **`[path/to/file1.py]`**
   - Purpose: [What this file does]
   - Key components: [Classes, functions, exports]

2. **`[path/to/file2.py]`**
   - Purpose: [What this file does]
   - Key components: [Classes, functions, exports]

### Existing Files to Modify

1. **`[path/to/existing.py]`**
   - Changes: [What needs to be modified]
   - Location: [Function/class to modify]

2. **`[path/to/another.py]`**
   - Changes: [What needs to be modified]
   - Location: [Function/class to modify]

### Files to Reference for Patterns

1. **`[path/to/pattern-example.py]`**
   - Pattern: [What pattern to follow]
   - Reason: [Why this is the reference]

---

## Data Models & API Contracts

### Database Schema (if applicable)

```sql
-- [Table 1]
CREATE TABLE [table_name] (
  id SERIAL PRIMARY KEY,
  [field1] [type] [constraints],
  [field2] [type] [constraints],
  created_at TIMESTAMP DEFAULT NOW()
);

-- [Table 2]
CREATE TABLE [table_name] (
  ...
);
```

### Type Definitions

```python
# [Model 1]
class [ModelName]:
    [field1]: [type]
    [field2]: [type]

# [Model 2]
class [ModelName]:
    [field1]: [type]
    [field2]: [type]
```

### API Contracts

**Endpoint 1: `[METHOD] /api/[path]`**

Request:
```json
{
  "[field]": "[type/example]",
  "[field]": "[type/example]"
}
```

Response (Success - 200):
```json
{
  "[field]": "[type/example]",
  "[field]": "[type/example]"
}
```

Response (Error - 4xx/5xx):
```json
{
  "error": "[error message pattern]",
  "details": "[additional context]"
}
```

**Endpoint 2: `[METHOD] /api/[path]`**
[Same structure...]

---

## Implementation Steps

Execute these steps in order. Each step has a clear outcome.

### Step 1: [Action Description]
**Outcome:** [What will exist/work after this step]

**Details:**
- [Specific action 1]
- [Specific action 2]
- [Specific action 3]

**Code Example:**
```python
# [Brief code snippet showing the implementation]
```

**Validation:** [How to verify this step is complete]

---

### Step 2: [Action Description]
**Outcome:** [What will exist/work after this step]

**Details:**
- [Specific action 1]
- [Specific action 2]

**Code Example:**
```python
# [Brief code snippet]
```

**Validation:** [How to verify this step is complete]

---

[Continue for all implementation steps...]

---

## Test Cases

### Unit Tests

**Test 1: `test_[functionality]`**
```python
def test_[functionality]():
    # Arrange
    [setup code]

    # Act
    [action]

    # Assert
    assert [expected outcome]
```

**Test 2: `test_[edge_case]`**
```python
def test_[edge_case]():
    # [Test implementation]
```

[Continue for all unit tests...]

### Integration Tests

**Test 1: `test_[integration_scenario]`**
```python
def test_[integration_scenario]():
    # Test description: [What this tests]
    # Expected: [Expected outcome]
```

[Continue for integration tests...]

### Expected Test Coverage
- Unit test coverage: [percentage]% minimum
- Critical paths: 100% coverage
- Edge cases: [specific cases to cover]

---

## Error Handling

### Error Scenario 1: [Scenario Description]
**Trigger:** [What causes this error]
**Error Message:** "[Exact error message]"
**HTTP Status:** [Status code if API]
**Recovery:** [How the system should handle/recover]
**User Impact:** [What the user experiences]

### Error Scenario 2: [Scenario Description]
[Same structure...]

### Logging Requirements
- **Info level:** [What to log at info]
- **Warning level:** [What to log at warning]
- **Error level:** [What to log at error]

---

## Integration Points

### Integration 1: [System/Module Name]
**Connection Point:** [Where/how it connects]
**Data Flow:** [What data is exchanged]
**Dependencies:** [What this integration depends on]
**Error Handling:** [What happens if integration fails]

### Integration 2: [System/Module Name]
[Same structure...]

---

## Dependencies

### New Dependencies to Install

```bash
# [Package 1]
[package-name]==[version]  # [Purpose/reason]

# [Package 2]
[package-name]==[version]  # [Purpose/reason]
```

**Installation:**
```bash
poetry add [package-name]==[version]
# or
pip install [package-name]==[version]
```

### Existing Dependencies to Leverage
- **[Package Name]**: [How it's used in this feature]
- **[Package Name]**: [How it's used in this feature]

### Version Constraints
- Python: [version requirement]
- [Framework]: [version requirement]

---

## Effort Estimation

| Activity              | Estimated Time | Assumptions |
|-----------------------|----------------|-------------|
| Implementation        | [X hours]      | [Assumption 1, Assumption 2] |
| Unit Testing          | [X hours]      | [Assumption 1] |
| Integration Testing   | [X hours]      | [Assumption 1] |
| Documentation         | [X hours]      | [Assumption 1] |
| Code Review           | [X hours]      | [Assumption 1] |
| **Total**             | **[X hours]**  | **[Y days]** |

**Key Assumptions:**
1. [Assumption that affects estimate]
2. [Assumption that affects estimate]
3. [Assumption that affects estimate]

**Risks to Estimate:**
- [Risk 1]: Could add [X hours]
- [Risk 2]: Could add [X hours]

---

## Definition of Done

- ✅ All implementation steps completed
- ✅ All test cases pass
- ✅ Test coverage meets requirements
- ✅ Error handling tested
- ✅ Integration points validated
- ✅ Code formatted (Black)
- ✅ Linting passes (Ruff)
- ✅ Documentation updated
- ✅ Code reviewed and approved

---

*Generated by CDD Framework /plan command - Planner persona*
*Spec: [path to spec.yaml]*
