diff --git a/src/utils/ai.js b/src/utils/ai.js
index 36545eb..362a085 100644
--- a/src/utils/ai.js
+++ b/src/utils/ai.js
@@ -156,7 +156,7 @@ async function callBedrock(messages, model, temperature, maxTokens) {
 
   var BedrockModule = require('@aws-sdk/client-bedrock-runtime');
   var modelId = getBedrockModelId(model);
-  var isAnthropic = modelId.startsWith('anthropic.');
+  var isAnthropic = modelId.indexOf('anthropic.') !== -1;
 
   // Separate system message from chat messages
   var systemMsg = '';
diff --git a/src/utils/models.js b/src/utils/models.js
index 0ff74a5..1a9896c 100644
--- a/src/utils/models.js
+++ b/src/utils/models.js
@@ -27,24 +27,25 @@ var OPENROUTER_MODELS = [
 ];
 
 var BEDROCK_MODELS = [
-  // ── Anthropic vendor model (all verified on-demand from AWS docs 2026-03) ──
-  // Wide region availability unless noted
+  // ── Anthropic vendor model (verified from AWS docs 2026-03) ──
+  // Models marked "profile" require cross-region inference profiles (us. prefix)
+  // Models marked "on-demand" support direct single-region invocation
   { id: 'anthropic/vendor-model-opus-4-6', name: 'vendor model Opus 4.6', cost: '~$0.075', tag: 'BEST', category: 'premium',
-    bedrockId: 'anthropic.agent-config-opus-4-6-v1' },
+    bedrockId: 'us.anthropic.agent-config-opus-4-6-v1' },
   { id: 'anthropic/vendor-model-opus-4-5', name: 'vendor model Opus 4.5', cost: '~$0.075', tag: 'OPUS', category: 'premium',
-    bedrockId: 'anthropic.agent-config-opus-4-5-20251101-v1:0' },
+    bedrockId: 'us.anthropic.agent-config-opus-4-5-20251101-v1:0' },
   { id: 'anthropic/vendor-model-opus-4-1', name: 'vendor model Opus 4.1', cost: '~$0.075', tag: 'MEDICAL', category: 'premium',
     bedrockId: 'anthropic.agent-config-opus-4-1-20250805-v1:0', regions: ['us-east-1', 'us-east-2', 'us-west-2'] },
   { id: 'anthropic/vendor-model-sonnet-4-6', name: 'vendor model Sonnet 4.6', cost: '~$0.015', tag: 'RECOMMENDED', category: 'premium',
-    bedrockId: 'anthropic.agent-config-sonnet-4-6' },
+    bedrockId: 'us.anthropic.agent-config-sonnet-4-6' },
   { id: 'anthropic/vendor-model-sonnet-4-5', name: 'vendor model Sonnet 4.5', cost: '~$0.015', tag: 'SMART', category: 'premium',
-    bedrockId: 'anthropic.agent-config-sonnet-4-5-20250929-v1:0' },
+    bedrockId: 'us.anthropic.agent-config-sonnet-4-5-20250929-v1:0' },
   { id: 'anthropic/vendor-model-sonnet-4', name: 'vendor model Sonnet 4', cost: '~$0.015', tag: 'SOLID', category: 'premium',
-    bedrockId: 'anthropic.agent-config-sonnet-4-20250514-v1:0' },
+    bedrockId: 'us.anthropic.agent-config-sonnet-4-20250514-v1:0' },
   { id: 'anthropic/vendor-model-haiku-4-5', name: 'vendor model Haiku 4.5', cost: '~$0.003', tag: 'FAST', category: 'smart',
-    bedrockId: 'anthropic.agent-config-haiku-4-5-20251001-v1:0' },
+    bedrockId: 'us.anthropic.agent-config-haiku-4-5-20251001-v1:0' },
   { id: 'anthropic/vendor-model-3.5-haiku', name: 'vendor model 3.5 Haiku', cost: '~$0.002', tag: 'VALUE', category: 'smart',
-    bedrockId: 'anthropic.agent-config-3-5-haiku-20241022-v1:0', regions: ['us-west-2', 'us-east-1', 'us-east-2'] },
+    bedrockId: 'us.anthropic.agent-config-3-5-haiku-20241022-v1:0' },
 
   // ── Amazon Nova (on-demand, fast + cheap) ──
   { id: 'amazon/nova-pro', name: 'Amazon Nova Pro', cost: '~$0.008', tag: 'SMART', category: 'smart',