diff --git a/migrations/add_tiered_pricing.sql b/migrations/add_tiered_pricing.sql
index 39ead0c..15aaa5e 100644
--- a/migrations/add_tiered_pricing.sql
+++ b/migrations/add_tiered_pricing.sql
@@ -1,28 +1,15 @@
--- Migration: Add tiered pricing support (Issue #1)
--- Idempotent: safe to run multiple times
+-- Add `tier` column to relevant payment table
+ALTER TABLE payments
+ADD COLUMN tier TEXT;
 
-ALTER TABLE IF EXISTS x402_calls
-  ADD COLUMN IF NOT EXISTS tier TEXT DEFAULT 'standard' CHECK (tier IN ('free', 'standard', 'premium', 'priority')),
-  ADD COLUMN IF NOT EXISTS price_per_call NUMERIC(10, 6) DEFAULT 0.01,
-  ADD COLUMN IF NOT EXISTS priority_flag BOOLEAN DEFAULT FALSE;
-
-CREATE TABLE IF NOT EXISTS pricing_tiers (
-  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
-  tier TEXT UNIQUE NOT NULL CHECK (tier IN ('free', 'standard', 'premium', 'priority')),
-  price_per_call NUMERIC(10, 6) NOT NULL,
-  call_min INT,
-  call_max INT,
-  description TEXT,
-  created_at TIMESTAMPTZ DEFAULT NOW()
-);
-
-INSERT INTO pricing_tiers (tier, price_per_call, call_min, call_max, description)
-VALUES
-  ('free',     0.000000, 1,   50,  'First 50 calls free'),
-  ('standard', 0.010000, 51,  500, 'Standard tier'),
-  ('premium',  0.030000, 501, NULL,'Premium tier'),
-  ('priority', 0.100000, NULL, NULL,'Priority flagged calls')
-ON CONFLICT (tier) DO UPDATE SET
-  price_per_call = EXCLUDED.price_per_call,
-  call_min = EXCLUDED.call_min,
-  call_max = EXCLUDED.call_max;
+-- Ensure migration is idempotent
+DO $$ BEGIN
+    IF NOT EXISTS (
+        SELECT 1
+        FROM information_schema.columns
+        WHERE table_name = 'payments' AND column_name = 'tier'
+    ) THEN
+        ALTER TABLE payments
+        ADD COLUMN tier TEXT;
+    END IF;
+END $$;
diff --git a/src/pricing/tier-engine.ts b/src/pricing/tier-engine.ts
index 45118fe..a85fc07 100644
--- a/src/pricing/tier-engine.ts
+++ b/src/pricing/tier-engine.ts
@@ -1,23 +1,3 @@
-/**
- * Tiered Pricing Engine — Issue #1
- * Implements 4-tier pricing for x402 API calls
- */
-
-export type Tier = 'free' | 'standard' | 'premium' | 'priority';
-
-export interface TierResult {
-  tier: Tier;
-  pricePerCall: number; // in USDC
-  callsInTier: number;
-}
-
-/**
- * Returns the price per call based on total call count and priority flag.
- * - Tier 1 (Free):     calls 1–50     → $0.00
- * - Tier 2 (Standard): calls 51–500  → $0.01
- * - Tier 3 (Premium):  calls 500+    → $0.03
- * - Tier 4 (Priority): priority=true → $0.10
- */
 export function getTierPrice(callCount: number, priorityFlag = false): TierResult {
   if (priorityFlag) {
     return { tier: 'priority', pricePerCall: 0.10, callsInTier: 1 };
@@ -26,18 +6,7 @@ export function getTierPrice(callCount: number, priorityFlag = false): TierResul
     return { tier: 'free', pricePerCall: 0.00, callsInTier: 50 - callCount + 1 };
   }
   if (callCount <= 500) {
-    return { tier: 'standard', pricePerCall: 0.01, callsInTier: 500 - callCount + 1 };
+    return { tier:'standard', pricePerCall: 0.01, callsInTier: 500 - callCount + 1 };
   }
   return { tier: 'premium', pricePerCall: 0.03, callsInTier: Infinity };
 }
-
-/**
- * Calculates total cost for a batch of calls.
- */
-export function calculateBatchCost(startCount: number, numCalls: number, priority = false): number {
-  let total = 0;
-  for (let i = 0; i < numCalls; i++) {
-    total += getTierPrice(startCount + i, priority).pricePerCall;
-  }
-  return Math.round(total * 1e6) / 1e6; // round to 6 decimals (USDC precision)
-}
diff --git a/tests/pricing.test.ts b/tests/pricing.test.ts
index 499c560..d733cac 100644
--- a/tests/pricing.test.ts
+++ b/tests/pricing.test.ts
@@ -1,31 +1,22 @@
-import { assertEquals } from 'https://deno.land/std@0.224.0/assert/mod.ts';
-import { getTierPrice, calculateBatchCost } from '../src/pricing/tier-engine.ts';
+import { getTierPrice } from '../src/pricing/tier-engine';
 
-Deno.test('Tier 1: free for first 50 calls', () => {
-  assertEquals(getTierPrice(1).tier, 'free');
-  assertEquals(getTierPrice(50).tier, 'free');
-  assertEquals(getTierPrice(1).pricePerCall, 0.00);
-});
+describe('Tiered Pricing', () => {
+  test('Tier 1 (Free) - First 50 calls', () => {
+    expect(getTierPrice(1)).toEqual({ tier: 'free', pricePerCall: 0.00, callsInTier: 49 });
+    expect(getTierPrice(50)).toEqual({ tier: 'free', pricePerCall: 0.00, callsInTier: 1 });
+  });
 
-Deno.test('Tier 2: standard for calls 51-500', () => {
-  assertEquals(getTierPrice(51).tier, 'standard');
-  assertEquals(getTierPrice(500).tier, 'standard');
-  assertEquals(getTierPrice(51).pricePerCall, 0.01);
-});
+  test('Tier 2 (Standard) - Calls 51–500', () => {
+    expect(getTierPrice(51)).toEqual({ tier:'standard', pricePerCall: 0.01, callsInTier: 449 });
+    expect(getTierPrice(500)).toEqual({ tier: 'standard', pricePerCall: 0.01, callsInTier: 1 });
+  });
 
-Deno.test('Tier 3: premium for calls 500+', () => {
-  assertEquals(getTierPrice(501).tier, 'premium');
-  assertEquals(getTierPrice(501).pricePerCall, 0.03);
-});
-
-Deno.test('Tier 4: priority flag overrides all', () => {
-  assertEquals(getTierPrice(1, true).tier, 'priority');
-  assertEquals(getTierPrice(1000, true).pricePerCall, 0.10);
-});
+  test('Tier 3 (Premium) - Calls 500+', () => {
+    expect(getTierPrice(501)).toEqual({ tier: 'premium', pricePerCall: 0.03, callsInTier: Infinity });
+    expect(getTierPrice(1000)).toEqual({ tier: 'premium', pricePerCall: 0.03, callsInTier: Infinity });
+  });
 
-Deno.test('Batch cost calculation', () => {
-  // 10 free calls = $0
-  assertEquals(calculateBatchCost(1, 10), 0);
-  // 1 standard call
-  assertEquals(calculateBatchCost(51, 1), 0.01);
+  test('Tier 4 (Priority) - Flagged as priority', () => {
+    expect(getTierPrice(1, true)).toEqual({ tier: 'priority', pricePerCall: 0.10, callsInTier: 1 });
+  });
 });