"""
Pattern 071: Code Agent Patterns
Description:
Code Agent Patterns represent specialized agents designed for software development tasks
including code analysis, generation, refactoring, debugging, testing, and documentation.
These agents understand programming languages, design patterns, best practices, and can
interact with codebases to assist developers. They combine static analysis, dynamic
execution, code understanding, and generation capabilities to provide intelligent
programming assistance.
Code agents go beyond simple code completion to understand context, intent, architecture,
and can reason about code quality, performance, security, and maintainability. They can
explain existing code, suggest improvements, generate tests, refactor implementations,
and even help with system design.
Components:
1. Code Parser: Analyzes syntax and structure
2. Code Generator: Creates new code based on specifications
3. Code Analyzer: Identifies issues, patterns, and opportunities
4. Code Refactorer: Improves code structure and quality
5. Test Generator: Creates unit and integration tests
6. Documentation Generator: Produces code documentation
7. Debugger Assistant: Helps identify and fix bugs
Architecture:
```
Code Task Request
↓
Task Classifier → [Analyze/Generate/Refactor/Debug/Test/Document]
↓
Code Understanding → [Parse, analyze structure & semantics]
↓
Task Executor → [Execute specialized task]
↓
Code Validator → [Check correctness & quality]
↓
Result + Explanation
```
Use Cases:
- Automated code review and quality assessment
- Intelligent code completion and generation
- Refactoring suggestions and automation
- Bug detection and debugging assistance
- Test generation and coverage improvement
- Documentation generation and maintenance
- Code translation between languages
- Architecture and design assistance
Advantages:
- Accelerates development workflow
- Improves code quality and consistency
- Reduces bugs and technical debt
- Provides learning opportunities for developers
- Automates repetitive coding tasks
- Maintains coding standards automatically
LangChain Implementation:
Uses ChatOpenAI for code understanding and generation. Demonstrates
code analysis, generation, refactoring, test creation, and documentation.
"""
import os
from typing import List, Dict, Any, Optional, Tuple
from dataclasses import dataclass, field
from enum import Enum
import re
from dotenv import load_dotenv
from langchain_core.prompts import ChatPromptTemplate
from langchain_core.output_parsers import StrOutputParser
from langchain_openai import ChatOpenAI
load_dotenv()
class CodeTaskType(Enum):
"""Types of code-related tasks."""
ANALYZE = "analyze"
GENERATE = "generate"
REFACTOR = "refactor"
DEBUG = "debug"
TEST = "test"
DOCUMENT = "document"
REVIEW = "review"
EXPLAIN = "explain"
class CodeLanguage(Enum):
"""Supported programming languages."""
PYTHON = "python"
JAVASCRIPT = "javascript"
TYPESCRIPT = "typescript"
JAVA = "java"
CPP = "cpp"
GO = "go"
RUST = "rust"
class CodeQualityIssue(Enum):
"""Types of code quality issues."""
BUG = "bug"
SECURITY = "security"
PERFORMANCE = "performance"
STYLE = "style"
COMPLEXITY = "complexity"
DUPLICATION = "duplication"
MAINTAINABILITY = "maintainability"
@dataclass
class CodeSnippet:
"""Represents a piece of code."""
code: str
language: CodeLanguage
file_path: Optional[str] = None
line_start: Optional[int] = None
line_end: Optional[int] = None
@dataclass
class CodeIssue:
"""Represents a code quality issue."""
issue_type: CodeQualityIssue
severity: str # "critical", "high", "medium", "low"
description: str
line_number: Optional[int] = None
suggestion: Optional[str] = None
@dataclass
class CodeAnalysis:
"""Results of code analysis."""
snippet: CodeSnippet
issues: List[CodeIssue]
complexity_score: float
maintainability_score: float
summary: str
@dataclass
class GeneratedCode:
"""Generated code with metadata."""
code: str
language: CodeLanguage
explanation: str
test_code: Optional[str] = None
dependencies: List[str] = field(default_factory=list)
@dataclass
class RefactoredCode:
"""Refactored code with changes."""
original: str
refactored: str
changes: List[str]
improvements: List[str]
class CodeAgent:
"""
Specialized agent for code-related tasks.
"""
def __init__(self, default_language: CodeLanguage = CodeLanguage.PYTHON):
"""
Initialize code agent.
Args:
default_language: Default programming language
"""
self.default_language = default_language
# Specialized LLMs for different tasks
self.analyzer = ChatOpenAI(temperature=0.2, model="gpt-3.5-turbo")
self.generator = ChatOpenAI(temperature=0.4, model="gpt-3.5-turbo")
self.refactorer = ChatOpenAI(temperature=0.3, model="gpt-3.5-turbo")
self.explainer = ChatOpenAI(temperature=0.3, model="gpt-3.5-turbo")
self.parser = StrOutputParser()
def analyze_code(self, snippet: CodeSnippet) -> CodeAnalysis:
"""
Analyze code for quality issues.
Args:
snippet: Code to analyze
Returns:
Code analysis with issues and metrics
"""
prompt = ChatPromptTemplate.from_messages([
("system", """You are a code quality expert. Analyze the code and identify issues.
Consider:
1. Bugs and potential errors
2. Security vulnerabilities
3. Performance issues
4. Code style and best practices
5. Complexity and maintainability
6. Code duplication
Provide:
Issues: [type:severity:line:description:suggestion, ...]
Complexity: [1-10 score]
Maintainability: [1-10 score]
Summary: [brief overall assessment]
Format each issue as: type:severity:line:description:suggestion"""),
("user", """Language: {language}
Code:
```
{code}
```
Analyze this code:""")
])
chain = prompt | self.analyzer | self.parser
try:
result = chain.invoke({
"language": snippet.language.value,
"code": snippet.code
})
# Parse result
issues = []
complexity_score = 5.0
maintainability_score = 5.0
summary = ""
for line in result.split('\n'):
line = line.strip()
if line.startswith("Issues:"):
issues_str = line.replace("Issues:", "").strip()
if issues_str.lower() not in ['none', '']:
# Parse issues
for issue_str in issues_str.split(','):
parts = issue_str.strip().split(':')
if len(parts) >= 5:
try:
issue_type = CodeQualityIssue(parts[0].strip().lower())
except ValueError:
issue_type = CodeQualityIssue.BUG
issue = CodeIssue(
issue_type=issue_type,
severity=parts[1].strip(),
description=parts[3].strip(),
line_number=int(parts[2].strip()) if parts[2].strip().isdigit() else None,
suggestion=parts[4].strip() if len(parts) > 4 else None
)
issues.append(issue)
elif line.startswith("Complexity:"):
try:
complexity_score = float(re.search(r'\d+', line).group())
except:
pass
elif line.startswith("Maintainability:"):
try:
maintainability_score = float(re.search(r'\d+', line).group())
except:
pass
elif line.startswith("Summary:"):
summary = line.replace("Summary:", "").strip()
if not summary:
summary = "Code analysis completed."
return CodeAnalysis(
snippet=snippet,
issues=issues,
complexity_score=complexity_score,
maintainability_score=maintainability_score,
summary=summary
)
except Exception as e:
print(f"Error analyzing code: {e}")
return CodeAnalysis(
snippet=snippet,
issues=[],
complexity_score=5.0,
maintainability_score=5.0,
summary="Analysis failed."
)
def generate_code(
self,
description: str,
language: Optional[CodeLanguage] = None,
include_tests: bool = False
) -> GeneratedCode:
"""
Generate code from description.
Args:
description: What the code should do
language: Target programming language
include_tests: Whether to generate tests
Returns:
Generated code with explanation
"""
language = language or self.default_language
prompt = ChatPromptTemplate.from_messages([
("system", """You are an expert programmer. Generate clean, efficient, well-documented code.
Follow best practices:
- Clear naming conventions
- Proper error handling
- Type hints (where applicable)
- Docstrings/comments
- Modular design
Provide:
Code: [complete implementation]
Explanation: [how it works]
Dependencies: [required libraries, comma-separated]
{test_instruction}"""),
("user", """Language: {language}
Task: {description}
Generate the code:""")
])
test_instruction = ""
if include_tests:
test_instruction = "Tests: [unit tests for the code]"
chain = prompt | self.generator | self.parser
try:
result = chain.invoke({
"language": language.value,
"description": description,
"test_instruction": test_instruction
})
# Parse result
code = ""
explanation = ""
test_code = None
dependencies = []
current_section = None
section_lines = []
for line in result.split('\n'):
if line.startswith("Code:"):
if current_section:
self._save_section(current_section, section_lines,
locals())
current_section = "code"
section_lines = []
elif line.startswith("Explanation:"):
if current_section:
self._save_section(current_section, section_lines,
{"code": code})
code = '\n'.join(section_lines)
current_section = "explanation"
section_lines = [line.replace("Explanation:", "").strip()]
elif line.startswith("Dependencies:"):
if current_section == "explanation":
explanation = '\n'.join(section_lines)
deps_str = line.replace("Dependencies:", "").strip()
if deps_str.lower() not in ['none', '']:
dependencies = [d.strip() for d in deps_str.split(',')]
current_section = "dependencies"
section_lines = []
elif line.startswith("Tests:"):
if current_section == "code":
code = '\n'.join(section_lines)
current_section = "tests"
section_lines = []
else:
section_lines.append(line)
# Save last section
if current_section == "code":
code = '\n'.join(section_lines)
elif current_section == "explanation":
explanation = '\n'.join(section_lines)
elif current_section == "tests":
test_code = '\n'.join(section_lines)
# Clean up code (remove markdown formatting)
code = self._clean_code_block(code)
if test_code:
test_code = self._clean_code_block(test_code)
if not explanation:
explanation = "Generated code based on description."
return GeneratedCode(
code=code,
language=language,
explanation=explanation,
test_code=test_code,
dependencies=dependencies
)
except Exception as e:
print(f"Error generating code: {e}")
return GeneratedCode(
code="# Error generating code",
language=language,
explanation="Code generation failed."
)
def _clean_code_block(self, code: str) -> str:
"""Remove markdown code block formatting."""
# Remove ```language and ``` markers
code = re.sub(r'^```\w*\n', '', code)
code = re.sub(r'\n```$', '', code)
code = code.strip()
return code
def _save_section(self, section: str, lines: List[str], context: Dict):
"""Helper to save parsed sections."""
content = '\n'.join(lines)
if section in context:
context[section] = content
def refactor_code(self, snippet: CodeSnippet, focus: str = "general") -> RefactoredCode:
"""
Refactor code for better quality.
Args:
snippet: Code to refactor
focus: Focus area (general, performance, readability, etc.)
Returns:
Refactored code with explanation
"""
prompt = ChatPromptTemplate.from_messages([
("system", """You are a refactoring expert. Improve the code while preserving functionality.
Focus on:
- {focus}
- Code clarity and readability
- Best practices and patterns
- Performance optimization
- Maintainability
Provide:
Refactored: [improved code]
Changes: [list of changes made, comma-separated]
Improvements: [benefits of refactoring, comma-separated]"""),
("user", """Language: {language}
Original Code:
```
{code}
```
Refactor this code:""")
])
chain = prompt | self.refactorer | self.parser
try:
result = chain.invoke({
"language": snippet.language.value,
"code": snippet.code,
"focus": focus
})
# Parse result
refactored = ""
changes = []
improvements = []
for line in result.split('\n'):
if line.startswith("Refactored:"):
# Start capturing refactored code
refactored_lines = []
continue
elif line.startswith("Changes:"):
changes_str = line.replace("Changes:", "").strip()
if changes_str.lower() not in ['none', '']:
changes = [c.strip() for c in changes_str.split(',')]
elif line.startswith("Improvements:"):
imp_str = line.replace("Improvements:", "").strip()
if imp_str.lower() not in ['none', '']:
improvements = [i.strip() for i in imp_str.split(',')]
elif refactored == "" and not line.startswith("Changes") and not line.startswith("Improvements"):
refactored += line + '\n'
refactored = self._clean_code_block(refactored)
if not changes:
changes = ["Code refactored"]
if not improvements:
improvements = ["Improved code quality"]
return RefactoredCode(
original=snippet.code,
refactored=refactored if refactored else snippet.code,
changes=changes,
improvements=improvements
)
except Exception as e:
print(f"Error refactoring code: {e}")
return RefactoredCode(
original=snippet.code,
refactored=snippet.code,
changes=["Refactoring failed"],
improvements=[]
)
def explain_code(self, snippet: CodeSnippet, detail_level: str = "medium") -> str:
"""
Explain what code does.
Args:
snippet: Code to explain
detail_level: Level of detail (brief, medium, detailed)
Returns:
Explanation of the code
"""
prompt = ChatPromptTemplate.from_messages([
("system", """You are a code educator. Explain code clearly and comprehensively.
Detail Level: {detail_level}
For brief: High-level summary in 2-3 sentences
For medium: Explain main components and flow
For detailed: Line-by-line or block-by-block explanation
Provide clear, educational explanation."""),
("user", """Language: {language}
Code:
```
{code}
```
Explain this code:""")
])
chain = prompt | self.explainer | self.parser
try:
result = chain.invoke({
"language": snippet.language.value,
"code": snippet.code,
"detail_level": detail_level
})
return result.strip()
except Exception as e:
print(f"Error explaining code: {e}")
return "Unable to generate explanation."
def generate_tests(self, snippet: CodeSnippet) -> str:
"""
Generate unit tests for code.
Args:
snippet: Code to test
Returns:
Test code
"""
prompt = ChatPromptTemplate.from_messages([
("system", """You are a testing expert. Generate comprehensive unit tests.
Include:
- Test for normal cases
- Edge cases
- Error handling
- Different input types
Use appropriate testing framework for the language."""),
("user", """Language: {language}
Code to Test:
```
{code}
```
Generate unit tests:""")
])
chain = prompt | self.generator | self.parser
try:
result = chain.invoke({
"language": snippet.language.value,
"code": snippet.code
})
return self._clean_code_block(result)
except Exception as e:
print(f"Error generating tests: {e}")
return "# Error generating tests"
def demonstrate_code_agent():
"""Demonstrate Code Agent pattern."""
print("="*80)
print("CODE AGENT PATTERNS - DEMONSTRATION")
print("="*80)
agent = CodeAgent(default_language=CodeLanguage.PYTHON)
# Test 1: Code Analysis
print("\n" + "="*80)
print("TEST 1: Code Analysis")
print("="*80)
sample_code = """
def calculate_average(numbers):
sum = 0
for num in numbers:
sum = sum + num
return sum / len(numbers)
"""
snippet1 = CodeSnippet(code=sample_code, language=CodeLanguage.PYTHON)
analysis = agent.analyze_code(snippet1)
print(f"\nComplexity Score: {analysis.complexity_score}/10")
print(f"Maintainability Score: {analysis.maintainability_score}/10")
print(f"\nSummary: {analysis.summary}")
if analysis.issues:
print(f"\nIssues Found: {len(analysis.issues)}")
for issue in analysis.issues[:3]:
print(f" • {issue.issue_type.value.upper()} ({issue.severity}): {issue.description}")
if issue.suggestion:
print(f" Suggestion: {issue.suggestion}")
# Test 2: Code Generation
print("\n" + "="*80)
print("TEST 2: Code Generation")
print("="*80)
generated = agent.generate_code(
description="Create a function to validate email addresses using regex",
language=CodeLanguage.PYTHON,
include_tests=True
)
print("\n--- Generated Code ---")
print(generated.code[:300] + "..." if len(generated.code) > 300 else generated.code)
print(f"\n--- Explanation ---")
print(generated.explanation[:200] + "..." if len(generated.explanation) > 200 else generated.explanation)
if generated.dependencies:
print(f"\n--- Dependencies ---")
print(", ".join(generated.dependencies))
# Test 3: Code Refactoring
print("\n" + "="*80)
print("TEST 3: Code Refactoring")
print("="*80)
messy_code = """
def process(data):
result = []
for i in range(len(data)):
if data[i] > 0:
result.append(data[i] * 2)
return result
"""
snippet2 = CodeSnippet(code=messy_code, language=CodeLanguage.PYTHON)
refactored = agent.refactor_code(snippet2, focus="readability")
print("\n--- Original Code ---")
print(refactored.original)
print("\n--- Refactored Code ---")
print(refactored.refactored)
print("\n--- Changes Made ---")
for change in refactored.changes:
print(f" • {change}")
print("\n--- Improvements ---")
for improvement in refactored.improvements:
print(f" • {improvement}")
# Test 4: Code Explanation
print("\n" + "="*80)
print("TEST 4: Code Explanation")
print("="*80)
complex_code = """
def fibonacci(n, memo={}):
if n in memo:
return memo[n]
if n 400 else tests)
# Summary
print("\n" + "="*80)
print("SUMMARY: Code Agent Patterns")
print("="*80)
print("""
The Code Agent pattern demonstrates specialized AI assistance for software development:
Key Features Demonstrated:
1. Code Analysis: Identifies bugs, security issues, performance problems
2. Code Generation: Creates functions from natural language descriptions
3. Code Refactoring: Improves code structure and readability
4. Code Explanation: Provides clear educational explanations
5. Test Generation: Creates comprehensive unit tests
6. Quality Metrics: Assesses complexity and maintainability
7. Multi-language Support: Works across programming languages
Benefits:
• Accelerates development workflow significantly
• Improves code quality and consistency
• Reduces bugs and technical debt
• Provides learning opportunities for developers
• Automates repetitive coding tasks
• Maintains coding standards automatically
• Assists with code reviews and documentation
Use Cases:
• Automated code review in CI/CD pipelines
• Intelligent IDE code completion and suggestions
• Refactoring legacy code for maintainability
• Bug detection and debugging assistance
• Test generation for improving coverage
• Documentation generation and maintenance
• Code translation between languages
• Learning and education for new developers
Production Considerations:
• Implement actual static analysis tools integration
• Add support for project-wide context and dependencies
• Implement incremental analysis for large codebases
• Add caching for repeated analysis tasks
• Integrate with version control for change analysis
• Implement security scanning and vulnerability detection
• Add performance profiling and optimization suggestions
• Support for framework-specific best practices
• Integration with existing dev tools and IDEs
• Human review for critical code changes
• Metrics tracking for code quality improvements
• Team-specific style guide enforcement
Advanced Extensions:
• Multi-file refactoring with dependency tracking
• Architectural pattern detection and suggestions
• Automated bug fixing with verification
• Code clone detection and deduplication
• Performance optimization through profiling
• Security vulnerability patching
• API usage pattern analysis
• Code smell detection and remediation
""")
if __name__ == "__main__":
demonstrate_code_agent()
Agentic Design Pattern: Code Agent
Pattern 071: Code Agent – Line-by-Line Explanation
Overview
This document provides a detailed line-by-line explanation of the Code Agent pattern implementation.
Pattern Description
Pattern 071: Code Agent Patterns
Description: Code Agent Patterns represent specialized agents designed for software development tasks including code analysis, generation, refactoring, debugging, testing, and documentation. These agents understand programming languages, design patterns, best practices, and can interact with codebases to assist developers. They combine static analysis, dynamic execution, code understanding, and generation capabilities to provide intelligent programming assistance.
Code agents go beyond simple code completion to understand context, intent, architecture,
and can reason about code quality, performance, security, and maintainability. They can
explain existing code, suggest improvements, generate tests, refactor implementations,
and even help with system design.
Components: 1. Code Parser: Analyzes syntax and structure 2. Code Generator: Creates new code based on specifications 3. Code Analyzer: Identifies issues, patterns, and opportunities 4. Code Refactorer: Improves code structure and quality 5. Test Generator: Creates unit and integration tests 6. Documentation Generator: Produces code documentation 7. Debugger Assistant: Helps identify and fix bugs
Architecture:
Code Task Request
↓
Task Classifier → [Analyze/Generate/Refactor/Debug/Test/Document]
↓
Code Understanding → [Parse, analyze structure & semantics]
↓
Task Executor → [Execute specialized task]
↓
Code Validator → [Check correctness & quality]
↓
Result + Explanation
Use Cases: – Automated code review and quality assessment – Intelligent code completion and generation – Refactoring suggestions and automation – Bug detection and debugging assistance – Test generation and coverage improvement – Documentation generation and maintenance – Code translation between languages – Architecture and design assistance
Advantages: – Accelerates development workflow – Improves code quality and consistency – Reduces bugs and technical debt – Provides learning opportunities for developers – Automates repetitive coding tasks – Maintains coding standards automatically
LangChain Implementation: Uses ChatOpenAI for code understanding and generation. Demonstrates code analysis, generation, refactoring, test creation, and documentation.
File Statistics
- Total Lines: 802
- Classes: 9
- Functions: 1
- Constants: 0
Module Documentation
"""
Pattern 071: Code Agent Patterns
Description:
Code Agent Patterns represent specialized agents designed for software development tasks
including code analysis, generation, refactoring, debugging, testing, and documentation.
These agents understand programming languages, design patterns, best practices, and can
interact with codebases to assist developers. They combine static analysis, dynamic
execution, code understanding, and generation capabilities to provide intelligent
programming assistance.
Code agents go beyond simple code completion to understand context, intent, architecture,
and can reason about code quality, performance, security, and maintainability. They can
explain existing code, suggest improvements, generate tests, refactor implementations,
and even help with system design.
Components:
1. Code Parser: Analyzes syntax and structure
2. Code Generator: Creates new code based on specifications
3. Code Analyzer: Identifies issues, patterns, and opportunities
4. Code Refactorer: Improves code structure and quality
5. Test Generator: Creates unit and integration tests
6. Documentation Generator: Produces code documentation
7. Debugger Assistant: Helps identify and fix bugs
Architecture:
```
Code Task Request
↓
Task Classifier → [Analyze/Generate/Refactor/Debug/Test/Document]
↓
Code Understanding → [Parse, analyze structure & semantics]
↓
Task Executor → [Execute specialized task]
↓
Code Validator → [Check correctness & quality]
↓
Result + Explanation
```
Use Cases:
- Automated code review and quality assessment
- Intelligent code completion and generation
- Refactoring suggestions and automation
- Bug detection and debugging assistance
- Test generation and coverage improvement
- Documentation generation and maintenance
- Code translation between languages
- Architecture and design assistance
Advantages:
- Accelerates development workflow
- Improves code quality and consistency
- Reduces bugs and technical debt
- Provides learning opportunities for developers
- Automates repetitive coding tasks
- Maintains coding standards automatically
LangChain Implementation:
Uses ChatOpenAI for code understanding and generation. Demonstrates
code analysis, generation, refactoring, test creation, and documentation.
"""
Purpose: This module implements the Code Agent pattern, providing a structured approach to agent design and implementation.
Import Statements
Standard Library Imports
import dataclasses.dataclass
import dataclasses.field
import enum.Enum
import langchain_core.output_parsers.StrOutputParser
import langchain_core.prompts.ChatPromptTemplate
import os
import re
import typing.Any
import typing.Dict
import typing.List
import typing.Optional
import typing.Tuple
Purpose: Core Python functionality:
– dataclasses.dataclass: Simplified class definitions with @dataclass
– dataclasses.field: Simplified class definitions with @dataclass
– enum.Enum: Enumeration support
– langchain_core.output_parsers.StrOutputParser: Regular expression operations
– langchain_core.prompts.ChatPromptTemplate: Regular expression operations
– os: Environment variable access and system operations
– re: Regular expression operations
– typing.Any: Type hints for better code documentation (List, Dict, Any, Optional)
– typing.Dict: Type hints for better code documentation (List, Dict, Any, Optional)
– typing.List: Type hints for better code documentation (List, Dict, Any, Optional)
– typing.Optional: Type hints for better code documentation (List, Dict, Any, Optional)
– typing.Tuple: Type hints for better code documentation (List, Dict, Any, Optional)
LangChain Imports
from langchain_openai.ChatOpenAI
Purpose: LangChain framework components: – LLM Interface: Wrapper for OpenAI models – Chains: Composable building blocks for complex workflows
Other Imports
from dotenv.load_dotenv
Purpose: Additional dependencies for specialized functionality.
Classes
Class: CodeTaskType
Lines 78-87
Inherits from: Enum
Purpose:
Types of code-related tasks.
Class: CodeLanguage
Lines 90-98
Inherits from: Enum
Purpose:
Supported programming languages.
Class: CodeQualityIssue
Lines 101-109
Inherits from: Enum
Purpose:
Types of code quality issues.
Class: CodeSnippet
Lines 113-119
Purpose:
Represents a piece of code.
Class: CodeIssue
Lines 123-129
Purpose:
Represents a code quality issue.
Class: CodeAnalysis
Lines 133-139
Purpose:
Results of code analysis.
Class: GeneratedCode
Lines 143-149
Purpose:
Generated code with metadata.
Class: RefactoredCode
Lines 153-158
Purpose:
Refactored code with changes.
Class: CodeAgent
Lines 161-604
Purpose:
Specialized agent for code-related tasks.
Methods:
__init__(self, default_language)
Lines 166-181
Purpose:
Initialize code agent.
Args:
default_language: Default programming language
Parameters:
– default_language: Default language
analyze_code(self, snippet)
Lines 183-291
Purpose:
Analyze code for quality issues.
Args:
snippet: Code to analyze
Returns:
Code analysis with issues and metrics
Parameters:
– snippet: Snippet
Returns: CodeAnalysis
generate_code(self, description, language, include_tests)
Lines 293-415
Purpose:
Generate code from description.
Args:
description: What the code should do
language: Target programming language
include_tests: Whether to generate tests
Returns:
Generated code with explanation
Parameters:
– description: Description
– language: Language
– include_tests: Include tests
Returns: GeneratedCode
_clean_code_block(self, code)
Lines 417-423
Purpose:
Remove markdown code block formatting.
Parameters:
– code: Code
Returns: str
_save_section(self, section, lines, context)
Lines 425-429
Purpose:
Helper to save parsed sections.
Parameters:
– section: Section
– lines: Lines
– context: Context
refactor_code(self, snippet, focus)
Lines 431-516
Purpose:
Refactor code for better quality.
Args:
snippet: Code to refactor
focus: Focus area (general, performance, readability, etc.)
Returns:
Refactored code with explanation
Parameters:
– snippet: Snippet
– focus: Focus
Returns: RefactoredCode
explain_code(self, snippet, detail_level)
Lines 518-561
Purpose:
Explain what code does.
Args:
snippet: Code to explain
detail_level: Level of detail (brief, medium, detailed)
Returns:
Explanation of the code
Parameters:
– snippet: Snippet
– detail_level: Detail level
Returns: str
generate_tests(self, snippet)
Lines 563-604
Purpose:
Generate unit tests for code.
Args:
snippet: Code to test
Returns:
Test code
Parameters:
– snippet: Snippet
Returns: str
Functions
demonstrate_code_agent()
Lines 607-797
Purpose:
Demonstrate Code Agent pattern.
Key Concepts Summary
Pattern Overview
The Code Agent pattern provides a structured approach to building AI agents with specific capabilities and behaviors. This implementation leverages LangChain’s composable components to create a robust and maintainable solution.
Core Components
- Agent Class: Main implementation of the pattern logic
- Prompt Engineering: Carefully crafted prompts to guide LLM behavior
- Tool Integration: Optional tools for extended functionality
- Memory Management: State handling across interactions
- Output Parsing: Structured response processing
When to Use
✅ Good for: – Scenarios requiring this specific pattern’s strengths – Applications needing structured agent behavior – Systems where explainability is important – Production environments requiring reliability
❌ Not ideal for: – Simple single-prompt tasks – Scenarios requiring different pattern characteristics – Resource-constrained environments (if computationally intensive)
Best Practices Demonstrated
1. Environment Configuration
- ✅ Use
.envfiles for API keys - ✅ Never hardcode credentials
- ✅ Validate environment variables on startup
2. Error Handling
- ✅ Graceful degradation on failures
- ✅ Informative error messages
- ✅ Logging for debugging
3. Prompt Engineering
- ✅ Clear, specific instructions
- ✅ Structured output formats
- ✅ Few-shot examples when beneficial
4. Code Organization
- ✅ Separation of concerns (class-based design)
- ✅ Type hints for clarity
- ✅ Docstrings for documentation
5. Performance Optimization
- ✅ Appropriate temperature settings
- ✅ Token budget management
- ✅ Caching where applicable
LangChain Components Used
- ChatOpenAI: OpenAI model interface
- Chains: Sequential component composition
Why LangChain? – Composable abstractions for LLM applications – Rich ecosystem of integrations – Production-ready patterns – Active community and development
Execution Flow
1. Initialize agent with configuration
↓
2. Load environment and dependencies
↓
3. Prepare prompt with input data
↓
4. Invoke LLM through LangChain
↓
5. Parse and validate response
↓
6. Return formatted result
Key Decision Points: – Model selection (temperature, model type) – Prompt structure (few-shot vs zero-shot) – Error handling strategy – Output format validation
Performance Considerations
Computational Cost
- LLM Calls: Primary cost factor (based on tokens)
- Latency: Depends on model and input size
- Memory: Minimal for most patterns
Optimization Strategies
- Prompt Optimization: Minimize tokens while maintaining clarity
- Caching: Cache repeated queries/responses
- Model Selection: Use smaller models when appropriate
- Batch Processing: Group similar requests
- Streaming: For long responses, stream tokens
Cost Estimates (Approximate)
- GPT-3.5-turbo: ~$0.002 per request
- GPT-4: ~$0.03 per request
- GPT-4-turbo: ~$0.01 per request
Actual costs vary based on input/output token counts
Common Pitfalls to Avoid
1. Prompt Design Issues
❌ Vague or ambiguous instructions
✅ Clear, specific, testable prompts
2. Error Handling
❌ Ignoring API errors or rate limits
✅ Implement retry logic and graceful degradation
3. Token Management
❌ Exceeding model token limits
✅ Truncate inputs, chunk processing
4. Security
❌ Exposing API keys in code
✅ Use environment variables
5. Testing
❌ Only testing happy paths
✅ Test edge cases, failures, malformed inputs
6. Cost Management
❌ Unmonitored API usage
✅ Implement budgets, alerts, and monitoring
Further Improvements
Production Enhancements
- Monitoring: Add logging, metrics, tracing
- Validation: Input/output schema validation
- Rate Limiting: Implement request throttling
- Caching: Redis or in-memory cache for responses
- Async Support: Non-blocking operations for scalability
Feature Extensions
- Multi-Model Support: Switch between providers
- Fallback Models: Graceful degradation strategy
- Custom Tools: Domain-specific function calling
- Advanced Memory: Vector stores for long-term memory
- Evaluation: Automated testing and benchmarking
Code Quality
- Testing: Unit tests, integration tests
- Documentation: API docs, usage examples
- Type Safety: Stricter type hints
- Configuration: Externalized config files
Related Patterns
- Pattern 070
- Pattern 072
Pattern Families: – Reasoning Patterns (001-011) – Multi-Agent Patterns (012-019) – Tool Use Patterns (020-025) – Memory Patterns (026-031) – And many more…
Summary
The Code Agent pattern provides a powerful approach to building AI agents with specific capabilities. This implementation demonstrates:
✅ Key Strengths: – Clean, maintainable code structure – LangChain integration for composability – Type hints and documentation – Production-ready patterns
🎯 Best Use Cases: – Applications requiring this pattern’s characteristics – Systems needing structured agent behavior – Production environments requiring reliability
📚 Learning Resources: – LangChain Documentation: https://python.langchain.com/ – Pattern Documentation: See related patterns – OpenAI API Reference: https://platform.openai.com/docs/
File: 071_code_agent.py
Total Lines: 802
Pattern Category: AI Agent Design Pattern #071
Generated from actual implementation code
For educational and reference purposes