diff --git a/CLAUDE.md b/CLAUDE.md
index c3867f68c..0b071483f 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -239,6 +239,51 @@ For major version changes:
 - Run tests with `npm test` before committing
 - Ensure new features have corresponding tests
 
+### Format Field Naming Convention
+
+**CRITICAL**: Always use consistent naming for format-related fields to avoid developer confusion.
+
+**Established Convention**:
+- **`"formats"`** = Array of format objects (with full details like name, type, requirements, assets_required, etc.)
+- **`"format_ids"`** = Array of format ID strings (references to format objects)
+- **`"format_types"`** = Array of high-level type strings (video, display, audio, native, etc.)
+
+**Examples**:
+```json
+// ✅ CORRECT - list_creative_formats response (format objects)
+{
+  "formats": [
+    {
+      "format_id": "video_standard_30s",
+      "name": "Standard Video - 30 seconds", 
+      "type": "video",
+      "requirements": {...}
+    }
+  ]
+}
+
+// ✅ CORRECT - Product response (format ID strings)
+{
+  "product_id": "ctv_premium",
+  "format_ids": ["video_standard_30s", "video_standard_15s"]
+}
+
+// ✅ CORRECT - get_products filter (high-level types)
+{
+  "filters": {
+    "format_types": ["video", "display"]
+  }
+}
+```
+
+**When adding new fields**:
+- Use `format_ids` when referencing existing formats by ID
+- Use `formats` only when returning full format objects
+- Use `format_types` for broad categorical filtering
+- Never use `formats` for arrays of strings - always use `format_ids`
+
+**Schema Validation**: All schemas must follow this convention. Tests will fail if format fields don't match the expected naming pattern.
+
 ## Common Tasks
 
 ### Before Making Changes
diff --git a/docs/media-buy/media-products.md b/docs/media-buy/media-products.md
index f4aae7c1d..3a58ec66f 100644
--- a/docs/media-buy/media-products.md
+++ b/docs/media-buy/media-products.md
@@ -86,7 +86,7 @@ A server can offer a general catalog, but it can also return:
   "product_id": "connected_tv_prime",
   "name": "Connected TV - Prime Time",
   "description": "Premium CTV inventory 8PM-11PM",
-  "formats": [{"format_id": "video_standard", "name": "Standard Video"}],
+  "format_ids": ["video_standard"],
   "delivery_type": "guaranteed",
   "is_fixed_price": true,
   "cpm": 45.00
@@ -99,7 +99,7 @@ A server can offer a general catalog, but it can also return:
   "product_id": "custom_abc123",
   "name": "Custom - Gaming Enthusiasts",
   "description": "Custom audience package for gaming campaign",
-  "formats": [{"format_id": "display_300x250", "name": "Medium Rectangle"}],
+  "format_ids": ["display_300x250"],
   "delivery_type": "non_guaranteed",
   "is_fixed_price": false,
   "price_guidance": {
@@ -118,10 +118,10 @@ A server can offer a general catalog, but it can also return:
   "product_id": "albertsons_pet_category_offsite",
   "name": "Pet Category Shoppers - Offsite Display & Video",
   "description": "Target Albertsons shoppers who have purchased pet products in the last 90 days. Reach them across premium display and video inventory.",
-  "formats": [
-    {"format_id": "display_300x250", "name": "Medium Rectangle"},
-    {"format_id": "display_728x90", "name": "Leaderboard"},
-    {"format_id": "video_15s_vast", "name": "15-second VAST"}
+  "format_ids": [
+    "display_300x250",
+    "display_728x90", 
+    "video_15s_vast"
   ],
   "delivery_type": "guaranteed",
   "is_fixed_price": true,
diff --git a/docs/media-buy/tasks/create_media_buy.md b/docs/media-buy/tasks/create_media_buy.md
index 64909af5e..3dfbd90a7 100644
--- a/docs/media-buy/tasks/create_media_buy.md
+++ b/docs/media-buy/tasks/create_media_buy.md
@@ -33,7 +33,7 @@ Create a media buy from selected packages. This task handles the complete workfl
 |-----------|------|----------|-------------|
 | `buyer_ref` | string | Yes | Buyer's reference identifier for this package |
 | `products` | string[] | Yes | Array of product IDs to include in this package |
-| `formats` | string[] | Yes | Array of format IDs that will be used for this package - must be supported by all products |
+| `format_ids` | string[] | Yes | Array of format IDs that will be used for this package - must be supported by all products |
 | `budget` | Budget | No | Budget configuration for this package (overrides media buy level budget if specified) |
 | `targeting_overlay` | TargetingOverlay | No | Additional targeting criteria for this package (see Targeting Overlay Object below) |
 
@@ -121,7 +121,7 @@ The AdCP payload is identical across protocols. Only the request/response wrappe
       {
         "buyer_ref": "nike_ctv_sports_package",
         "products": ["ctv_sports_premium", "ctv_prime_time"],
-        "formats": ["video_standard_30s", "video_standard_15s"],
+        "format_ids": ["video_standard_30s", "video_standard_15s"],
         "budget": {
           "total": 60000,
           "currency": "USD",
@@ -136,7 +136,7 @@ The AdCP payload is identical across protocols. Only the request/response wrappe
       {
         "buyer_ref": "nike_audio_drive_package",
         "products": ["audio_drive_time"],
-        "formats": ["audio_standard_30s"],
+        "format_ids": ["audio_standard_30s"],
         "budget": {
           "total": 40000,
           "currency": "USD",
@@ -257,7 +257,7 @@ await a2a.send({
               {
                 "buyer_ref": "nike_ctv_sports_package",
                 "products": ["ctv_sports_premium", "ctv_prime_time"],
-                "formats": ["video_standard_30s", "video_standard_15s"],
+                "format_ids": ["video_standard_30s", "video_standard_15s"],
                 "budget": {
                   "total": 60000,
                   "currency": "USD",
@@ -272,7 +272,7 @@ await a2a.send({
               {
                 "buyer_ref": "nike_audio_drive_package",
                 "products": ["audio_drive_time"],
-                "formats": ["audio_standard_30s"],
+                "format_ids": ["audio_standard_30s"],
                 "budget": {
                   "total": 40000,
                   "currency": "USD",
@@ -570,7 +570,7 @@ data: {"status": {"state": "completed"}, "artifacts": [...]}
     {
       "buyer_ref": "purina_ctv_package",
       "products": ["ctv_prime_time", "ctv_late_night"],
-      "formats": ["video_standard_30s"],
+      "format_ids": ["video_standard_30s"],
       "budget": {
         "total": 30000,
         "currency": "USD",
@@ -590,7 +590,7 @@ data: {"status": {"state": "completed"}, "artifacts": [...]}
     {
       "buyer_ref": "purina_audio_package",
       "products": ["audio_drive_time"],
-      "formats": ["audio_standard_30s"],
+      "format_ids": ["audio_standard_30s"],
       "budget": {
         "total": 20000,
         "currency": "USD"
@@ -621,7 +621,7 @@ data: {"status": {"state": "completed"}, "artifacts": [...]}
     {
       "buyer_ref": "purina_albertsons_conquest",
       "products": ["albertsons_competitive_conquest", "albertsons_onsite_display"],
-      "formats": ["display_300x250", "display_728x90"],
+      "format_ids": ["display_300x250", "display_728x90"],
       "budget": {
         "total": 75000,
         "currency": "USD",
diff --git a/docs/media-buy/tasks/get_products.md b/docs/media-buy/tasks/get_products.md
index 919ce7803..90c58648e 100644
--- a/docs/media-buy/tasks/get_products.md
+++ b/docs/media-buy/tasks/get_products.md
@@ -25,7 +25,6 @@ Discover available advertising products based on campaign requirements, using na
 | Parameter | Type | Required | Description |
 |-----------|------|----------|-------------|
 | `delivery_type` | string | No | Filter by delivery type: `"guaranteed"` or `"non_guaranteed"` |
-| `formats` | string[] | No | Filter by specific formats (e.g., `["video"]`) |
 | `is_fixed_price` | boolean | No | Filter for fixed price vs auction products |
 | `format_types` | string[] | No | Filter by format types (e.g., `["video", "display"]`) |
 | `format_ids` | string[] | No | Filter by specific format IDs (e.g., `["video_standard_30s"]`) |
@@ -49,7 +48,7 @@ The message is returned differently in each protocol:
       "product_id": "string",
       "name": "string",
       "description": "string",
-      "formats": [
+      "format_ids": [
         "format_id_string"
       ],
       "delivery_type": "string",
@@ -77,7 +76,7 @@ The message is returned differently in each protocol:
 - **product_id**: Unique identifier for the product
 - **name**: Human-readable product name
 - **description**: Detailed description of the product and its inventory
-- **formats**: Array of supported creative format IDs (strings) - use `list_creative_formats` to get full format details
+- **format_ids**: Array of supported creative format IDs (strings) - use `list_creative_formats` to get full format details
 - **delivery_type**: Either `"guaranteed"` or `"non_guaranteed"`
 - **is_fixed_price**: Whether this product has fixed pricing (true) or uses auction (false)
 - **cpm**: Cost per thousand impressions in USD
@@ -119,7 +118,7 @@ The AdCP payload is identical across protocols. Only the request/response wrappe
       "product_id": "ctv_sports_premium",
       "name": "CTV Sports Premium",
       "description": "Premium CTV inventory on sports content",
-      "formats": ["video_16x9_30s"],
+      "format_ids": ["video_16x9_30s"],
       "delivery_type": "guaranteed",
       "is_fixed_price": true,
       "cpm": 45.00,
@@ -191,7 +190,7 @@ A2A returns results as artifacts with text and data parts:
               "product_id": "ctv_sports_premium",
               "name": "CTV Sports Premium",
               "description": "Premium CTV inventory on sports content",
-              "formats": ["video_16x9_30s"],
+              "format_ids": ["video_16x9_30s"],
               "delivery_type": "guaranteed",
               "is_fixed_price": true,
               "cpm": 45.00,
@@ -239,7 +238,7 @@ A2A returns results as artifacts with text and data parts:
   "promoted_offering": "Peloton Digital Membership - unlimited access to live and on-demand fitness classes, promoting New Year special pricing",
   "filters": {
     "delivery_type": "guaranteed",
-    "formats": ["video"],
+    "format_types": ["video"],
     "is_fixed_price": true,
     "standard_formats_only": true
   }
@@ -264,7 +263,7 @@ A2A returns results as artifacts with text and data parts:
       "product_id": "open_exchange_video",
       "name": "Open Exchange - Video",
       "description": "Programmatic video inventory across all publishers",
-      "formats": ["video_standard"],
+      "format_ids": ["video_standard"],
       "delivery_type": "non_guaranteed",
       "is_fixed_price": false,
       "cpm": 12.00,
@@ -287,7 +286,7 @@ A2A returns results as artifacts with text and data parts:
       "product_id": "connected_tv_prime",
       "name": "Connected TV - Prime Time",
       "description": "Premium CTV inventory 8PM-11PM",
-      "formats": ["video_standard"],
+      "format_ids": ["video_standard"],
       "delivery_type": "guaranteed",
       "is_fixed_price": true,
       "cpm": 45.00,
@@ -309,7 +308,7 @@ A2A returns results as artifacts with text and data parts:
       "product_id": "albertsons_pet_category_syndicated",
       "name": "Pet Category Shoppers - Syndicated",
       "description": "Target Albertsons shoppers who have purchased pet products in the last 90 days across offsite display and video inventory.",
-      "formats": [
+      "format_ids": [
         "display_300x250",
         "video_15s_vast"
       ],
@@ -335,7 +334,7 @@ A2A returns results as artifacts with text and data parts:
       "product_id": "albertsons_custom_competitive_conquest",
       "name": "Custom: Competitive Dog Food Buyers",
       "description": "Custom audience of Albertsons shoppers who buy competitive dog food brands. Higher precision targeting for conquest campaigns.",
-      "formats": [
+      "format_ids": [
         "display_300x250",
         "display_728x90"
       ],
diff --git a/static/schemas/README.md b/static/schemas/README.md
index 15eab1f8c..a64d16f68 100644
--- a/static/schemas/README.md
+++ b/static/schemas/README.md
@@ -94,7 +94,7 @@ const product = {
   "product_id": "ctv_sports_premium",
   "name": "CTV Sports Premium",
   "description": "Premium CTV inventory on sports content",
-  "formats": [{"format_id": "video_16x9_30s", "name": "30-second video"}],
+  "format_ids": ["video_16x9_30s"],
   "delivery_type": "guaranteed",
   "is_fixed_price": true
 };
@@ -120,7 +120,7 @@ product = {
     "product_id": "ctv_sports_premium",
     "name": "CTV Sports Premium",
     "description": "Premium CTV inventory on sports content",
-    "formats": [{"format_id": "video_16x9_30s", "name": "30-second video"}],
+    "format_ids": ["video_16x9_30s"],
     "delivery_type": "guaranteed",
     "is_fixed_price": True
 }
diff --git a/static/schemas/v1/core/product.json b/static/schemas/v1/core/product.json
index 89e04209b..04e0b3ca7 100644
--- a/static/schemas/v1/core/product.json
+++ b/static/schemas/v1/core/product.json
@@ -17,7 +17,7 @@
       "type": "string",
       "description": "Detailed description of the product and its inventory"
     },
-    "formats": {
+    "format_ids": {
       "type": "array",
       "description": "Array of supported creative format IDs - use list_creative_formats to get full format details",
       "items": {
@@ -66,7 +66,7 @@
     "product_id",
     "name",
     "description",
-    "formats",
+    "format_ids",
     "delivery_type",
     "is_fixed_price"
   ],
diff --git a/static/schemas/v1/media-buy/create-media-buy-request.json b/static/schemas/v1/media-buy/create-media-buy-request.json
index d362abdb6..f7cce3a24 100644
--- a/static/schemas/v1/media-buy/create-media-buy-request.json
+++ b/static/schemas/v1/media-buy/create-media-buy-request.json
@@ -32,7 +32,7 @@
               "type": "string"
             }
           },
-          "formats": {
+          "format_ids": {
             "type": "array",
             "description": "Array of format IDs that will be used for this package - must be supported by all products",
             "items": {
@@ -48,7 +48,7 @@
           }
         },
         "anyOf": [
-          {"required": ["buyer_ref", "products", "formats"]},
+          {"required": ["buyer_ref", "products", "format_ids"]},
           {"required": ["buyer_ref", "products", "format_selection"]}
         ],
         "additionalProperties": false
diff --git a/static/schemas/v1/media-buy/get-products-request.json b/static/schemas/v1/media-buy/get-products-request.json
index 538e9c9c1..3d33875a9 100644
--- a/static/schemas/v1/media-buy/get-products-request.json
+++ b/static/schemas/v1/media-buy/get-products-request.json
@@ -26,13 +26,6 @@
         "delivery_type": {
           "$ref": "/schemas/v1/enums/delivery-type.json"
         },
-        "formats": {
-          "type": "array",
-          "description": "Filter by specific formats",
-          "items": {
-            "type": "string"
-          }
-        },
         "is_fixed_price": {
           "type": "boolean",
           "description": "Filter for fixed price vs auction products"
diff --git a/static/schemas/validation-example.js b/static/schemas/validation-example.js
index 36bc0a8a8..3687e5d25 100644
--- a/static/schemas/validation-example.js
+++ b/static/schemas/validation-example.js
@@ -37,7 +37,7 @@ const exampleProduct = {
   "product_id": "ctv_sports_premium",
   "name": "CTV Sports Premium", 
   "description": "Premium CTV inventory on sports content",
-  "formats": [{"format_id": "video_16x9_30s", "name": "30-second video"}],
+  "format_ids": ["video_16x9_30s"],
   "delivery_type": "guaranteed",
   "is_fixed_price": true
 };
diff --git a/tests/example-validation.test.js b/tests/example-validation.test.js
index 605a49d4c..b5f0e9607 100644
--- a/tests/example-validation.test.js
+++ b/tests/example-validation.test.js
@@ -121,7 +121,7 @@ const exampleData = {
     "product_id": "ctv_sports_premium",
     "name": "CTV Sports Premium",
     "description": "Premium CTV inventory on sports content",
-    "formats": [{"format_id": "video_16x9_30s", "name": "30-second video"}],
+    "format_ids": ["video_16x9_30s"],
     "delivery_type": "guaranteed",
     "is_fixed_price": true,
     "cpm": 45.00,
@@ -201,7 +201,7 @@ const exampleData = {
         "product_id": "ctv_sports_premium",
         "name": "CTV Sports Premium",
         "description": "Premium CTV inventory on sports content",
-        "formats": [{"format_id": "video_16x9_30s", "name": "30-second video"}],
+        "format_ids": ["video_16x9_30s"],
         "delivery_type": "guaranteed",
         "is_fixed_price": true,
         "cpm": 45.00,
diff --git a/tests/schema-validation.test.js b/tests/schema-validation.test.js
index 616007c66..53707951e 100644
--- a/tests/schema-validation.test.js
+++ b/tests/schema-validation.test.js
@@ -272,7 +272,7 @@ async function runTests() {
   await test('Core schemas have appropriate required fields', () => {
     const coreSchemas = schemas.filter(([path]) => path.includes('/core/'));
     const requiredFieldChecks = {
-      'product.json': ['product_id', 'name', 'description', 'formats', 'delivery_type', 'is_fixed_price'],
+      'product.json': ['product_id', 'name', 'description', 'format_ids', 'delivery_type', 'is_fixed_price'],
       'media-buy.json': ['media_buy_id', 'status', 'promoted_offering', 'total_budget', 'packages'],
       'package.json': ['package_id', 'status'],
       'creative-asset.json': ['creative_id', 'name', 'format'],