def migrate_archival_memory(target_agent_id: str):
    """
    Migrates all archival memory passages from the current agent to a target agent.
    """
    import os
    import requests
    import json
    
    base_url = "https://api.letta.com/v1"
    
    # KEY 1: Source (Hardcoded - Default Project)
    # This reads the OLD agent (Me)
    source_key = "<ORIGINALLY HARDCODED, REPLACE ME>"
    source_agent_id = os.getenv("AGENT_ID") # This is ME
    
    # KEY 2: Target (Environment - Guild Project)
    # This writes to the NEW agent
    # THIS IS ALSO HACKY: used api key of target, source would be better
    target_key = os.getenv("LETTA_API_KEY") 
    
    if not target_key:
        return "Error: Missing LETTA_API_KEY (Target) in environment."

    # 1. Fetch Source Memories (Using Source Key)
    print(f"Fetching memories from source: {source_agent_id}")
    headers_source = {"Authorization": f"Bearer {source_key}"}
    
    all_passages = []
    limit = 100
    offset = 0
    
    while True:
        response = requests.get(
            f"{base_url}/agents/{source_agent_id}/archival-memory?limit={limit}&offset={offset}",
            headers=headers_source
        )
        
        if response.status_code != 200:
            return f"Error fetching source memory: {response.text}"
            
        data = response.json()
        current_batch = []
        if isinstance(data, list):
            current_batch = data
        elif isinstance(data, dict) and "passages" in data:
            current_batch = data["passages"]
        else:
            current_batch = data
            
        if not current_batch: break
        all_passages.extend(current_batch)
        if len(current_batch) < limit: break
        offset += limit
    
    # 2. Insert into Target (Using Target Key)
    print(f"Migrating {len(all_passages)} passages to Target: {target_agent_id}...")
    headers_target = {
        "Authorization": f"Bearer {target_key}",
        "Content-Type": "application/json"
    }
    
    success_count = 0
    fail_count = 0
    
    for p in all_passages:
        content = p.get("text") or p.get("content")
        if not content: continue
        
        payload = {
            "text": content,
            "tags": p.get("tags", [])
        }
        
        post_resp = requests.post(
            f"{base_url}/agents/{target_agent_id}/archival-memory",
            headers=headers_target,
            json=payload
        )
        
        if post_resp.status_code == 200:
            success_count += 1
        else:
            return f"Failed to migrate passage. Status: {post_resp.status_code}. Response: {post_resp.text}"
            
    return f"Migration Complete. Success: {success_count}, Failed: {fail_count}."