diff --git a/README.md b/README.md
index 1a5b81d..c04a1cd 100644
--- a/README.md
+++ b/README.md
@@ -11,9 +11,10 @@ pip install paysgator
 ## Usage
 
 ```python
+import os
 from paysgator import PaysgatorClient
 
-client = PaysgatorClient(api_key="YOUR_API_KEY")
+client = PaysgatorClient(api_key=os.getenv("PAYS_GATOR_API_KEY"))
 
 # Create a payment
 payment = client.payments.create(
diff --git a/pyproject.toml b/pyproject.toml
index ff08145..11b57a2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,7 +18,7 @@ classifiers = [
 ]
 dependencies = [
     "requests>=2.25.1",
-    "pydantic>=2.0.0"
+    "pydantic==2.12.5"
 ]
 
 [project.urls]
diff --git a/src/paysgator/client.py b/src/paysgator/client.py
index a067367..8e65014 100644
--- a/src/paysgator/client.py
+++ b/src/paysgator/client.py
@@ -70,7 +70,7 @@ def set_base_url(self, url: str):
 
     def request(self, method: str, endpoint: str, data: Optional[dict] = None) -> dict:
         url = f"{self.BASE_URL}{endpoint}"
-        response = self.session.request(method, url, json=data)
+        response = self.session.request(method, url, json=data, timeout=30)
         
         if response.status_code >= 400:
              raise APIError(response.status_code, response.text)
diff --git a/src/paysgator/exceptions.py b/src/paysgator/exceptions.py
index 3067741..bf9302f 100644
--- a/src/paysgator/exceptions.py
+++ b/src/paysgator/exceptions.py
@@ -10,5 +10,5 @@ class APIError(PaysgatorError):
     """Raised when the API returns an error"""
     def __init__(self, status_code: int, message: str):
         self.status_code = status_code
-        self.message = message
-        super().__init__(f"API Error {status_code}: {message}")
+        self._message = message  # internal use only; not exposed in str representation
+        super().__init__(f"API Error {status_code}")
diff --git a/src/paysgator/models.py b/src/paysgator/models.py
index 8863e2d..d32ff3c 100644
--- a/src/paysgator/models.py
+++ b/src/paysgator/models.py
@@ -1,4 +1,5 @@
 from typing import List, Optional, Dict, Any, Union
+from decimal import Decimal
 from enum import Enum
 from pydantic import BaseModel, Field
 
@@ -7,10 +8,10 @@ class Mode(str, Enum):
     TEST = "TEST"
 
 class PaymentCreateRequest(BaseModel):
-    amount: float
+    amount: Decimal
     currency: str
     external_transaction_id: Optional[str] = Field(None, alias="externalTransactionId")
-    payment_methods: Optional[List[str]] = Field(None, alias="payment_methods")
+    payment_methods: Optional[List[str]] = Field(None, alias="paymentMethods")
     fields: Optional[List[str]] = None
     return_url: Optional[str] = Field(None, alias="returnUrl")
     metadata: Optional[Dict[str, Any]] = None
@@ -34,13 +35,13 @@ class Customer(BaseModel):
 class PaymentConfirmRequest(BaseModel):
     payment_link_id: str = Field(..., alias="paymentLinkId")
     payment_method: str = Field(..., alias="paymentMethod")
-    payment_fields: Optional[Dict[str, Any]] = Field(None, alias="payment_fields")
+    payment_fields: Optional[Dict[str, Any]] = Field(None, alias="paymentFields")
     customer: Optional[Customer] = None
 
 class PaymentConfirmResponseData(BaseModel):
     transaction_id: str = Field(..., alias="transactionId")
-    fee: float
-    net_amount: float = Field(..., alias="netAmount")
+    fee: Decimal
+    net_amount: Decimal = Field(..., alias="netAmount")
 
 class PaymentConfirmResponse(BaseModel):
     success: bool
@@ -62,7 +63,7 @@ class SubscriptionResponse(BaseModel):
 
 class TransactionResponse(BaseModel):
     id: str
-    amount: float
+    amount: Decimal
     currency: str
     status: str
     method: Optional[str] = None
@@ -73,5 +74,5 @@ class TransactionResponse(BaseModel):
 class WalletBalanceResponse(BaseModel):
     wallet_id: str = Field(..., alias="walletId")
     currency: str
-    balance: str
+    balance: Decimal
     mode: str
diff --git a/test_sdk.py b/test_sdk.py
index 7ee8b76..191c7a5 100644
--- a/test_sdk.py
+++ b/test_sdk.py
@@ -1,22 +1,18 @@
-from src.paysgator.client import PaysgatorClient
+from paysgator import PaysgatorClient
 
 #Mpesa direct charge test 
 
-api_key = "<Api Key>"
+import os
 
-wallet_id = "<Wallet Id>"
+api_key = os.environ.get("PAYSGATOR_API_KEY", "<Api Key>")
 
-client = PaysgatorClient(api_key, wallet_id)
+client = PaysgatorClient(api_key=api_key)
 
-link = client.payment_links.create(
-    title="Test Product",
+link = client.payments.create(
     amount=50.0,
     currency="MZN",
-    methods=["MPESA"],
-    payment_fields={
-        "phoneNumber":""
-    },
-    confirm=True,
+    payment_methods=["MPESA"],
+    return_url="https://example.com/callback"
 )
 
 print(link)
\ No newline at end of file