In this tutorial, we devise how to orchestrate a fully functional, tool-using medical prior-authorization agent powered by Gemini. We walk through each component step by step, from securely configuring the model to building realistic external tools and finally constructing an intelligent agent loop that reasons, acts, and responds entirely through structured JSON. As we progress, we see how the system thinks, retrieves evidence, and interacts with simulated medical systems to complete a complex workflow. Check out the FULL CODES here.
!pip install -q -U google-generative-ai
import google.generativeai as genai
from google.colab import userdata
import os
import getpass
import json
import time
try:
GOOGLE_API_KEY = userdata.get('GOOGLE_API_KEY')
except:
print("Please enter your Google API Key:")
GOOGLE_API_KEY = getpass.getpass("API Key: ")
genai.configure(api_key=GOOGLE_API_KEY)
print("\n🔍 Scanning for available models...")
available_models = [m.name for m in genai.list_models()]
target_model = ""
if 'models/gemini-1.5-flash' in available_models:
target_model="gemini-1.5-flash"
elif 'models/gemini-1.5-flash-001' in available_models:
target_model="gemini-1.5-flash-001"
elif 'models/gemini-pro' in available_models:
target_model="gemini-pro"
else:
for m in available_models:
if 'generateContent' in genai.get_model(m).supported_generation_methods:
target_model = m
break
if not target_model:
raise ValueError("❌ No text generation models found for this API key.")
print(f"✅ Selected Model: {target_model}")
model = genai.GenerativeModel(target_model)We set up our environment and automatically detect the best available Gemini model. We configure the API key securely and let the system choose the most capable model without hardcoding anything. This ensures that we start the tutorial with a clean, flexible, and reliable foundation. Check out the FULL CODES here.
class MedicalTools:
def __init__(self):
self.ehr_docs = [
"Patient: John Doe | DOB: 1980-05-12",
"Visit 2023-01-10: Diagnosed with Type 2 Diabetes. Prescribed Metformin.",
"Visit 2023-04-15: Patient reports severe GI distress with Metformin. Discontinued.",
"Visit 2023-04-20: BMI recorded at 32.5. A1C is 8.4%.",
"Visit 2023-05-01: Doctor recommends starting Ozempic (Semaglutide)."
]
def search_ehr(self, query):
print(f" 🔎 [Tool] Searching EHR for: '{query}'...")
results = [doc for doc in self.ehr_docs if any(q.lower() in doc.lower() for q in query.split())]
if not results:
return "No records found."
return "\n".join(results)
def submit_prior_auth(self, drug_name, justification):
print(f" 📤 [Tool] Submitting claim for {drug_name}...")
justification_lower = justification.lower()
if "metformin" in justification_lower and ("discontinued" in justification_lower or "intolerance" in justification_lower):
if "bmi" in justification_lower and "32" in justification_lower:
return "SUCCESS: Authorization Approved. Auth ID: #998877"
return "DENIED: Policy requires proof of (1) Metformin failure and (2) BMI > 30."We define the medical tools that our agent can use during the workflow. We simulate an EHR search and a prior-authorization submission system so the agent has real actions to perform. By doing this, we ground the agent’s reasoning in tool-enabled interactions rather than plain text generation. Check out the FULL CODES here.
class AgenticSystem:
def __init__(self, model, tools):
self.model = model
self.tools = tools
self.history = []
self.max_steps = 6
self.system_prompt = """
You are an expert Medical Prior Authorization Agent.
Your goal is to get approval for a medical procedure/drug.
You have access to these tools:
1. search_ehr(query)
2. submit_prior_auth(drug_name, justification)
RULES:
1. ALWAYS think before you act.
2. You MUST output your response in STRICT JSON format:
{
"thought": "Your reasoning here",
"action": "tool_name_or_finish",
"action_input": "argument_string_or_dict"
}
3. Do not guess patient data. Use 'search_ehr'.
4. If you have the evidence, use 'submit_prior_auth'.
5. If the task is done, use action "finish".
"""
We initialize the agent and provide its full system prompt. We define the rules, the JSON response format, and the expectation that the agent must think before acting. This gives us a controlled, deterministic structure for building a safe and traceable agent loop. Check out the FULL CODES here.
def execute_tool(self, action_name, action_input):
if action_name == "search_ehr":
return self.tools.search_ehr(action_input)
elif action_name == "submit_prior_auth":
if isinstance(action_input, str):
return "Error: submit_prior_auth requires a dictionary."
return self.tools.submit_prior_auth(**action_input)
else:
return "Error: Unknown tool."
def run(self, objective):
print(f"🤖 AGENT STARTING. Objective: {objective}\n" + "-"*50)
self.history.append(f"User: {objective}")
for i in range(self.max_steps):
print(f"\n🔄 STEP {i+1}")
prompt = self.system_prompt + "\n\nHistory:\n" + "\n".join(self.history) + "\n\nNext JSON:"
try:
response = self.model.generate_content(prompt)
text_response = response.text.strip().replace("```json", "").replace("```", "")
agent_decision = json.loads(text_response)
except Exception as e:
print(f" ⚠️ Error parsing AI response. Retrying... ({e})")
continue
print(f" 🧠 THOUGHT: {agent_decision['thought']}")
print(f" 👉 ACTION: {agent_decision['action']}")
if agent_decision['action'] == "finish":
print(f"\n✅ TASK COMPLETED: {agent_decision['action_input']}")
break
tool_result = self.execute_tool(agent_decision['action'], agent_decision['action_input'])
print(f" 👁️ OBSERVATION: {tool_result}")
self.history.append(f"Assistant: {text_response}")
self.history.append(f"System: {tool_result}")
if "SUCCESS" in str(tool_result):
print("\n🎉 SUCCESS! The Agent successfully navigated the insurance portal.")
breakWe implement the core agent loop where reasoning, tool execution, and observations happen step by step. We watch the agent decide its next action, execute tools, update history, and evaluate success conditions. This is where the agent truly comes alive and performs iterative reasoning. Check out the FULL CODES here.
tools_instance = MedicalTools()
agent = AgenticSystem(model, tools_instance)
agent.run("Please get prior authorization for Ozempic for patient John Doe.")We instantiate the tools and agent, then run the entire system end-to-end with a real objective. We see the full workflow unfold as the agent navigates through medical history, validates evidence, and attempts prior authorization. This final snippet demonstrates the complete pipeline working seamlessly.
In conclusion, we reflect on how this compact yet powerful framework enables us to design real-world agentic behaviors that go beyond simple text responses. We watch our agent plan, consult tools, gather evidence, and ultimately complete a structured insurance authorization task, entirely through autonomous reasoning. It provides confidence that we can now expand the system with additional tools, stronger policies, domain-specific logic, or even multi-agent collaboration.
Check out the FULL CODES here. Feel free to check out our GitHub Page for Tutorials, Codes and Notebooks. Also, feel free to follow us on Twitter and don’t forget to join our 100k+ ML SubReddit and Subscribe to our Newsletter.
Asif Razzaq is the CEO of Marktechpost Media Inc.. As a visionary entrepreneur and engineer, Asif is committed to harnessing the potential of Artificial Intelligence for social good. His most recent endeavor is the launch of an Artificial Intelligence Media Platform, Marktechpost, which stands out for its in-depth coverage of machine learning and deep learning news that is both technically sound and easily understandable by a wide audience. The platform boasts of over 2 million monthly views, illustrating its popularity among audiences.
