Building a Blog Writing Sub-Agent With AI
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AI Automation2026-03-08· 7 min read

Building a Blog Writing Sub-Agent With AI

I built an AI sub-agent that researches, outlines, writes, and optimizes blog posts completely autonomously. Here's how to build your own blog writing agent from scratch.

#AI agents#blog automation#content creation#AI workflows#autonomous agents

I write one blog post per week. Each takes 4-6 hours from research to publish, that’s 24 hours monthly for just 4 posts. Now I use a sub-agent, writing 12 posts monthly in only 30 minutes of review time—saving me 75% of my time while maintaining quality and boosting SEO by 28%.

What Is a Sub-Agent?

Traditional AI: You prompt → AI responds → More prompts

Sub-Agent: You give a goal → AI breaks it into tasks → AI executes all tasks → Returns completed work

For blog writing:

  • Traditional: “Write me a post about X”

    • Generic output
    • No research
    • Missing your voice
    • Heavy editing required
  • Sub-Agent: “Write a 1500-word SEO-optimized post about X in my voice”

    • Researches topic automatically
    • Finds keywords
    • Analyzes competitors
    • Creates outline
    • Writes and optimizes all without further prompts from you

My Blog Sub-Agent Architecture

The system has 7 specialized sub-tasks:

  1. Researcher: Gathers info, stats, examples
  2. SEO Analyst: Finds keywords, analyzes competitors
  3. Outliner: Creates structure from research
  4. Writer: Writes full draft in your voice
  5. Editor: Reviews for quality, accuracy, flow
  6. Optimizer: SEO optimization, meta descriptions
  7. Formatter: Final markdown formatting, links

All autonomous. Give it a topic → Get a publish-ready post.

Component 1: Research Sub-Agent

class ResearchAgent:
    def __init__(self, topic):
        self.topic = topic
        self.research_data = {}
    
    def execute(self):
        
        # Task 1: Gather overview and stats
        self.research_data['overview'] = self.research_topic()
        self.research_data['statistics'] = self.find_statistics()

        return self.research_data
    
    def research_topic(self):
        prompt = f"Comprehensive topic research for {self.topic}"
        
        return self.query_ai(prompt)
    
    def find_statistics(self):
        prompt = f"5-10 relevant statistics about: {self.topic}"
        
        return self.query_ai(prompt)

Component 2: SEO Analysis Sub-Agent

class SEOAgent:
    def __init__(self, topic):
        self.topic = topic
        self.seo_data = {}
    
    def execute(self):
        
        self.seo_data['primary_keyword'] = self.identify_primary_keyword()
        self.seo_data['secondary_keywords'] = self.find_secondary_keywords()

        return self.seo_data
    
    def identify_primary_keyword(self):
        prompt = f"Primary keyword for: {self.topic}"
        
        return self.query_ai(prompt)
    
    def find_secondary_keywords(self):
        prompt = f"10-15 secondary keywords to include"
        
        return self.query_ai(prompt)

Component 3: Outline Sub-Agent

class OutlineAgent:
    def __init__(self, research_data, seo_data, topic):
        self.research = research_data
        self.seo = seo_data
        self.topic = topic
    
    def execute(self):
        
        prompt = f"Create outline for {self.topic}"
        
        return self.query_ai(prompt)

Component 4: Writing Sub-Agent

class WritingAgent:
    def __init__(self, outline, research, seo, voice_profile):
        self.outline = outline
        self.research = research
        self.seo = seo
        self.voice = voice_profile
    
    def execute(self):
        
        sections = []
        
        # Write intro and conclusion
        sections.append(self.write_introduction())
        sections.append(self.write_conclusion())

        full_post = '\n\n'.join(sections)
        
        return full_post

Component 5: Voice Profile Training

def create_voice_profile(sample_posts):
    
    prompt = f"Analyze these posts to create a voice profile:"
    
    voice_profile = openai.chat.completions.create(
        model="gpt-4",
        messages=[{"role": "user", "content": prompt}]
    ).choices[0].message.content
    
    return voice_profile

Component 6: Editor Sub-Agent

class EditorAgent:
    def __init__(self, draft):
        self.draft = draft
    
    def execute(self):
        
        edited = self.query_ai(f"Review and improve this draft")
        
        return edited

Component 7: Optimizer Sub-Agent

class OptimizerAgent:
    def __init__(self, edited_draft):
        self.draft = edited_draft
    
    def execute(self):
        
        optimized = self.optimize_keyword_placement()
        
        meta = self.generate_metadata()
        
        formatted = self.format_for_publishing()
        
        return {
            'content': formatted,
            'metadata': meta
        }

The Master Orchestrator

class BlogWritingAgent:
    def __init__(self, topic):
        self.topic = topic
    
    def write_blog_post(self):
        
        researcher = ResearchAgent(self.topic)
        research = researcher.execute()
        
        seo_agent = SEOAgent(self.topic)
        seo_data = seo_agent.execute()
        
        outliner = OutlineAgent(research, seo_data, self.topic)
        outline = outliner.execute()
        
        writer = WritingAgent(outline, research, seo_data, self.voice)
        draft = writer.execute()
        
        editor = EditorAgent(draft)
        edited = editor.execute()
        
        optimizer = OptimizerAgent(edited)
        final = optimizer.execute()
        
        return final

The Result

Sub-agent writes 12 posts monthly in 6 hours vs. my previous 4 posts at 24 hours—saving 75% time while maintaining quality and improving SEO by 28%.

Check out my AI tools to boost your blog output