Deepseek

DeepSeek API Skill

Overview

Expert skill for using DeepSeek API - advanced coding assistant with 128K context and strong reasoning capabilities.

API Key

# API ключи: ~/.claude/.credentials.master.env
# Переменная: DEEPSEEK_API_KEY
DEEPSEEK_API_KEY=os.getenv('DEEPSEEK_API_KEY')
DEEPSEEK_BASE_URL=https://api.deepseek.com/v1
DEEPSEEK_MODEL=deepseek-chat

When to Use DeepSeek

Best for:

• Complex code generation and refactoring
• Large codebase analysis (128K context!)
• Code review and debugging
• Algorithm design
• Technical documentation
• Math and reasoning problems

Advantages:

• 128K context window (huge!)
• Strong coding capabilities
• Excellent reasoning
• Cost-effective (cheaper than GPT-5.x)
• Fast inference

Dependencies

pip install openai  # DeepSeek uses OpenAI-compatible API

Basic Usage

Chat Completion

from openai import OpenAI
import os

# DeepSeek uses OpenAI-compatible API
client = OpenAI(
    api_key=os.getenv('DEEPSEEK_API_KEY'),
    base_url=os.getenv('DEEPSEEK_BASE_URL', 'https://api.deepseek.com/v1')
)

def deepseek_chat(prompt: str, system_prompt: str = None,
                  model: str = "deepseek-chat"):
    """
    Chat with DeepSeek.

    Models:
        - deepseek-chat: General purpose, coding, refactoring (fast, smart)
        - deepseek-reasoner: Best for complex reasoning
    """
    messages = []

    if system_prompt:
        messages.append({"role": "system", "content": system_prompt})

    messages.append({"role": "user", "content": prompt})

    response = client.chat.completions.create(
        model=model,
        messages=messages,
        temperature=0.7,
        max_tokens=4096
    )

    return response.choices[0].message.content

Code Generation

def generate_code(task: str, language: str = "python"):
    """Generate code with DeepSeek."""

    system_prompt = f"""You are an expert {language} developer.
    Write clean, well-documented, production-ready code.
    Include type hints, docstrings, and error handling.
    Follow best practices and design patterns."""

    return deepseek_chat(
        prompt=task,
        system_prompt=system_prompt,
        model="deepseek-chat"
    )

Code Review

def review_code(code: str, focus: list = None):
    """Review code for issues and improvements."""

    focus_areas = focus or ["security", "performance", "readability", "best practices"]

    system_prompt = """You are a senior code reviewer.
    Analyze the code thoroughly and provide:
    1. Security issues (CRITICAL)
    2. Performance problems
    3. Code quality issues
    4. Suggestions for improvement
    5. Good practices found

    Be specific with line numbers and provide fixes."""

    prompt = f"""Review this code focusing on: {', '.join(focus_areas)}

{code}

Provide structured feedback."""

    return deepseek_chat(prompt, system_prompt, model="deepseek-chat")

Large Codebase Analysis (128K context!)

def analyze_codebase(files: dict):
    """
    Analyze multiple files at once using 128K context.

    Args:
        files: {"path/to/file.py": "file content", ...}
    """

    # Build context with all files
    context = "# Codebase Analysis\n\n"
    for path, content in files.items():
        context += f"## File: {path}\n```\n{content}\n```\n\n"

    system_prompt = """You are a senior software architect.
    Analyze this codebase and provide:
    1. Architecture overview
    2. Code quality assessment
    3. Potential issues and technical debt
    4. Suggestions for improvement
    5. Security concerns"""

    return deepseek_chat(context + "\nAnalyze this codebase.", system_prompt)

Reasoning Tasks

def solve_problem(problem: str):
    """Solve complex reasoning problem with DeepSeek Reasoner."""

    system_prompt = """You are an expert problem solver.
    Think step by step.
    Show your reasoning clearly.
    Verify your solution."""

    return deepseek_chat(
        prompt=problem,
        system_prompt=system_prompt,
        model="deepseek-reasoner"
    )

Advanced Patterns

Streaming Response

def stream_response(prompt: str):
    """Stream response for long outputs."""

    response = client.chat.completions.create(
        model="deepseek-chat",
        messages=[{"role": "user", "content": prompt}],
        stream=True
    )

    for chunk in response:
        if chunk.choices[0].delta.content:
            yield chunk.choices[0].delta.content

Function Calling

def with_functions(prompt: str, functions: list):
    """Use function calling with DeepSeek."""

    response = client.chat.completions.create(
        model="deepseek-chat",
        messages=[{"role": "user", "content": prompt}],
        tools=[{"type": "function", "function": f} for f in functions],
        tool_choice="auto"
    )

    return response.choices[0]

JSON Mode

def structured_output(prompt: str):
    """Get structured JSON output."""

    response = client.chat.completions.create(
        model="deepseek-chat",
        messages=[
            {"role": "system", "content": "Respond in valid JSON format only."},
            {"role": "user", "content": prompt}
        ],
        response_format={"type": "json_object"}
    )

    import json
    return json.loads(response.choices[0].message.content)

Use Case Templates

Refactor Code

def refactor_code(code: str, goals: list):
    """Refactor code with specific goals."""

    prompt = f"""Refactor this code with these goals:
{chr(10).join(f'- {g}' for g in goals)}

Original code:

{code}

Provide the refactored code with explanations."""

    return deepseek_chat(prompt, model="deepseek-chat")

Debug Code

def debug_code(code: str, error: str):
    """Debug code with error message."""

    prompt = f"""Debug this code that produces the following error:

Error: {error}

Code:

{code}

1. Explain what's causing the error
2. Provide the fixed code
3. Explain what was changed"""

    return deepseek_chat(prompt, model="deepseek-chat")

Generate Tests

def generate_tests(code: str, framework: str = "pytest"):
    """Generate tests for code."""

    prompt = f"""Generate comprehensive tests for this code using {framework}:

{code}

Include:
- Unit tests for each function
- Edge cases
- Error handling tests
- Integration tests if applicable"""

    return deepseek_chat(prompt, model="deepseek-chat")

API Pricing

Note: DeepSeek is ~10-20x cheaper than GPT-5.x!

Quick Reference

Tips

1. Use 128K context - можно загружать целые репозитории
2. deepseek-chat для кода/рефакторинга, deepseek-reasoner для сложного reasoning
3. Дешевле GPT-5.x - используй для heavy tasks
4. OpenAI-compatible - тот же синтаксис что и OpenAI
5. Streaming - используй для длинных ответов
6. JSON mode - для структурированных данных