diff --git a/dist/index.js b/dist/index.js
index 5fc82d7ca0f5fba1da3b24c15bb714f51b5aa178..e1a3e2c97774af3a5688c7052bd9a07d692fcc8f 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -1035,22 +1035,6 @@ var OpenAIChatLanguageModel = class {
         });
       }
     }
-    if (openaiOptions.serviceTier === "flex" && !modelCapabilities.supportsFlexProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "flex processing is only available for o3, o4-mini, and gpt-5 models"
-      });
-      baseArgs.service_tier = void 0;
-    }
-    if (openaiOptions.serviceTier === "priority" && !modelCapabilities.supportsPriorityProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported"
-      });
-      baseArgs.service_tier = void 0;
-    }
     const {
       tools: openaiTools2,
       toolChoice: openaiToolChoice,
@@ -5454,22 +5438,6 @@ var OpenAIResponsesLanguageModel = class {
         });
       }
     }
-    if ((openaiOptions == null ? void 0 : openaiOptions.serviceTier) === "flex" && !modelCapabilities.supportsFlexProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "flex processing is only available for o3, o4-mini, and gpt-5 models"
-      });
-      delete baseArgs.service_tier;
-    }
-    if ((openaiOptions == null ? void 0 : openaiOptions.serviceTier) === "priority" && !modelCapabilities.supportsPriorityProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported"
-      });
-      delete baseArgs.service_tier;
-    }
     const shellToolEnvType = (_k = (_j = (_i = tools == null ? void 0 : tools.find(
       (tool) => tool.type === "provider" && tool.id === "openai.shell"
     )) == null ? void 0 : _i.args) == null ? void 0 : _j.environment) == null ? void 0 : _k.type;
diff --git a/dist/index.mjs b/dist/index.mjs
index 589c4f76955bee692b8af36ea1d9a15121695d4a..6838ea0a362c8fe774527bb1126b8031ebfd3fab 100644
--- a/dist/index.mjs
+++ b/dist/index.mjs
@@ -1031,22 +1031,6 @@ var OpenAIChatLanguageModel = class {
         });
       }
     }
-    if (openaiOptions.serviceTier === "flex" && !modelCapabilities.supportsFlexProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "flex processing is only available for o3, o4-mini, and gpt-5 models"
-      });
-      baseArgs.service_tier = void 0;
-    }
-    if (openaiOptions.serviceTier === "priority" && !modelCapabilities.supportsPriorityProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported"
-      });
-      baseArgs.service_tier = void 0;
-    }
     const {
       tools: openaiTools2,
       toolChoice: openaiToolChoice,
@@ -5557,22 +5541,6 @@ var OpenAIResponsesLanguageModel = class {
         });
       }
     }
-    if ((openaiOptions == null ? void 0 : openaiOptions.serviceTier) === "flex" && !modelCapabilities.supportsFlexProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "flex processing is only available for o3, o4-mini, and gpt-5 models"
-      });
-      delete baseArgs.service_tier;
-    }
-    if ((openaiOptions == null ? void 0 : openaiOptions.serviceTier) === "priority" && !modelCapabilities.supportsPriorityProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported"
-      });
-      delete baseArgs.service_tier;
-    }
     const shellToolEnvType = (_k = (_j = (_i = tools == null ? void 0 : tools.find(
       (tool) => tool.type === "provider" && tool.id === "openai.shell"
     )) == null ? void 0 : _i.args) == null ? void 0 : _j.environment) == null ? void 0 : _k.type;
diff --git a/dist/internal/index.js b/dist/internal/index.js
index ad78b5df9359509091f4b8a1751dc34c03c74e32..ed92f56d8fe9c1442f741ef8d42d592ce9b28643 100644
--- a/dist/internal/index.js
+++ b/dist/internal/index.js
@@ -1070,22 +1070,6 @@ var OpenAIChatLanguageModel = class {
         });
       }
     }
-    if (openaiOptions.serviceTier === "flex" && !modelCapabilities.supportsFlexProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "flex processing is only available for o3, o4-mini, and gpt-5 models"
-      });
-      baseArgs.service_tier = void 0;
-    }
-    if (openaiOptions.serviceTier === "priority" && !modelCapabilities.supportsPriorityProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported"
-      });
-      baseArgs.service_tier = void 0;
-    }
     const {
       tools: openaiTools,
       toolChoice: openaiToolChoice,
@@ -5724,22 +5708,6 @@ var OpenAIResponsesLanguageModel = class {
         });
       }
     }
-    if ((openaiOptions == null ? void 0 : openaiOptions.serviceTier) === "flex" && !modelCapabilities.supportsFlexProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "flex processing is only available for o3, o4-mini, and gpt-5 models"
-      });
-      delete baseArgs.service_tier;
-    }
-    if ((openaiOptions == null ? void 0 : openaiOptions.serviceTier) === "priority" && !modelCapabilities.supportsPriorityProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported"
-      });
-      delete baseArgs.service_tier;
-    }
     const shellToolEnvType = (_k = (_j = (_i = tools == null ? void 0 : tools.find(
       (tool) => tool.type === "provider" && tool.id === "openai.shell"
     )) == null ? void 0 : _i.args) == null ? void 0 : _j.environment) == null ? void 0 : _k.type;
diff --git a/dist/internal/index.mjs b/dist/internal/index.mjs
index db7d6741c9ea615d577ea07722b469c144066268..f6b41b2832d2c8392072e0ecc1612e9e18b1b48e 100644
--- a/dist/internal/index.mjs
+++ b/dist/internal/index.mjs
@@ -1023,22 +1023,6 @@ var OpenAIChatLanguageModel = class {
         });
       }
     }
-    if (openaiOptions.serviceTier === "flex" && !modelCapabilities.supportsFlexProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "flex processing is only available for o3, o4-mini, and gpt-5 models"
-      });
-      baseArgs.service_tier = void 0;
-    }
-    if (openaiOptions.serviceTier === "priority" && !modelCapabilities.supportsPriorityProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported"
-      });
-      baseArgs.service_tier = void 0;
-    }
     const {
       tools: openaiTools,
       toolChoice: openaiToolChoice,
@@ -5802,22 +5786,6 @@ var OpenAIResponsesLanguageModel = class {
         });
       }
     }
-    if ((openaiOptions == null ? void 0 : openaiOptions.serviceTier) === "flex" && !modelCapabilities.supportsFlexProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "flex processing is only available for o3, o4-mini, and gpt-5 models"
-      });
-      delete baseArgs.service_tier;
-    }
-    if ((openaiOptions == null ? void 0 : openaiOptions.serviceTier) === "priority" && !modelCapabilities.supportsPriorityProcessing) {
-      warnings.push({
-        type: "unsupported",
-        feature: "serviceTier",
-        details: "priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported"
-      });
-      delete baseArgs.service_tier;
-    }
     const shellToolEnvType = (_k = (_j = (_i = tools == null ? void 0 : tools.find(
       (tool) => tool.type === "provider" && tool.id === "openai.shell"
     )) == null ? void 0 : _i.args) == null ? void 0 : _j.environment) == null ? void 0 : _k.type;
diff --git a/src/chat/openai-chat-language-model.ts b/src/chat/openai-chat-language-model.ts
index 009a58deea236c2be03adc5cd03f98ed9050fd7b..a606675d82fc72a0bab8d52ac99866100e7ffb1d 100644
--- a/src/chat/openai-chat-language-model.ts
+++ b/src/chat/openai-chat-language-model.ts
@@ -267,34 +267,6 @@ export class OpenAIChatLanguageModel implements LanguageModelV3 {
       }
     }
 
-    // Validate flex processing support
-    if (
-      openaiOptions.serviceTier === 'flex' &&
-      !modelCapabilities.supportsFlexProcessing
-    ) {
-      warnings.push({
-        type: 'unsupported',
-        feature: 'serviceTier',
-        details:
-          'flex processing is only available for o3, o4-mini, and gpt-5 models',
-      });
-      baseArgs.service_tier = undefined;
-    }
-
-    // Validate priority processing support
-    if (
-      openaiOptions.serviceTier === 'priority' &&
-      !modelCapabilities.supportsPriorityProcessing
-    ) {
-      warnings.push({
-        type: 'unsupported',
-        feature: 'serviceTier',
-        details:
-          'priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported',
-      });
-      baseArgs.service_tier = undefined;
-    }
-
     const {
       tools: openaiTools,
       toolChoice: openaiToolChoice,
diff --git a/src/responses/openai-responses-language-model.ts b/src/responses/openai-responses-language-model.ts
index 926e7ec713480353b969901f19c5d1d8cc883dab..ed457ce8f07a60ed48c47a3cbf11b2a7c6cf6415 100644
--- a/src/responses/openai-responses-language-model.ts
+++ b/src/responses/openai-responses-language-model.ts
@@ -433,36 +433,6 @@ export class OpenAIResponsesLanguageModel implements LanguageModelV3 {
       }
     }
 
-    // Validate flex processing support
-    if (
-      openaiOptions?.serviceTier === 'flex' &&
-      !modelCapabilities.supportsFlexProcessing
-    ) {
-      warnings.push({
-        type: 'unsupported',
-        feature: 'serviceTier',
-        details:
-          'flex processing is only available for o3, o4-mini, and gpt-5 models',
-      });
-      // Remove from args if not supported
-      delete (baseArgs as any).service_tier;
-    }
-
-    // Validate priority processing support
-    if (
-      openaiOptions?.serviceTier === 'priority' &&
-      !modelCapabilities.supportsPriorityProcessing
-    ) {
-      warnings.push({
-        type: 'unsupported',
-        feature: 'serviceTier',
-        details:
-          'priority processing is only available for supported models (gpt-4, gpt-5, gpt-5-mini, o3, o4-mini) and requires Enterprise access. gpt-5-nano is not supported',
-      });
-      // Remove from args if not supported
-      delete (baseArgs as any).service_tier;
-    }
-
     const shellToolEnvType = (
       tools?.find(
         tool => tool.type === 'provider' && tool.id === 'openai.shell',