From ed9a9b8096ca00a2ca80ee8e062e52bc2f24f4c0 Mon Sep 17 00:00:00 2001
From: Andrey Nering <andreynering@users.noreply.github.com>
Date: Fri, 24 Oct 2025 14:12:29 -0300
Subject: [PATCH] fix(bedrock): prefix model id with region automatically

---
 providers/anthropic/anthropic.go |  2 ++
 providers/anthropic/bedrock.go   | 13 +++++++++++++
 providertests/bedrock_test.go    |  8 ++++----
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/providers/anthropic/anthropic.go b/providers/anthropic/anthropic.go
index a40ec96712dba7a135f70542d5098c30286dc3a4..42f8d72f1039cabf9c85341120655b4a24125fa3 100644
--- a/providers/anthropic/anthropic.go
+++ b/providers/anthropic/anthropic.go
@@ -157,6 +157,8 @@ func (a *provider) LanguageModel(ctx context.Context, modelID string) (fantasy.L
 		)
 	}
 	if a.options.useBedrock {
+		modelID = bedrockPrefixModelWithRegion(modelID)
+
 		if a.options.skipAuth || a.options.apiKey != "" {
 			clientOptions = append(
 				clientOptions,
diff --git a/providers/anthropic/bedrock.go b/providers/anthropic/bedrock.go
index ae9b5a30976ba46d328a99874da948b55559e41d..8d9b94959210e57fde8fa594a67bfc8db8d27415 100644
--- a/providers/anthropic/bedrock.go
+++ b/providers/anthropic/bedrock.go
@@ -3,6 +3,7 @@ package anthropic
 import (
 	"cmp"
 	"os"
+	"strings"
 
 	"github.com/aws/aws-sdk-go-v2/aws"
 	"github.com/aws/smithy-go/auth/bearer"
@@ -14,3 +15,15 @@ func bedrockBasicAuthConfig(apiKey string) aws.Config {
 		BearerAuthTokenProvider: bearer.StaticTokenProvider{Token: bearer.Token{Value: apiKey}},
 	}
 }
+
+func bedrockPrefixModelWithRegion(modelID string) string {
+	region := os.Getenv("AWS_REGION")
+	if len(region) < 2 {
+		region = "us-east-1"
+	}
+	prefix := region[:2] + "."
+	if strings.HasPrefix(modelID, prefix) {
+		return modelID
+	}
+	return prefix + modelID
+}
diff --git a/providertests/bedrock_test.go b/providertests/bedrock_test.go
index 7eab1eb8407040623303f8480d98065c5cb44b5c..e377f3568d393a30b53d13604a8dcf1c9970d322 100644
--- a/providertests/bedrock_test.go
+++ b/providertests/bedrock_test.go
@@ -30,7 +30,7 @@ func builderBedrockClaude3Sonnet(t *testing.T, r *recorder.Recorder) (fantasy.La
 	if err != nil {
 		return nil, err
 	}
-	return provider.LanguageModel(t.Context(), "us.anthropic.claude-3-sonnet-20240229-v1:0")
+	return provider.LanguageModel(t.Context(), "anthropic.claude-3-sonnet-20240229-v1:0")
 }
 
 func builderBedrockClaude3Opus(t *testing.T, r *recorder.Recorder) (fantasy.LanguageModel, error) {
@@ -41,7 +41,7 @@ func builderBedrockClaude3Opus(t *testing.T, r *recorder.Recorder) (fantasy.Lang
 	if err != nil {
 		return nil, err
 	}
-	return provider.LanguageModel(t.Context(), "us.anthropic.claude-3-opus-20240229-v1:0")
+	return provider.LanguageModel(t.Context(), "anthropic.claude-3-opus-20240229-v1:0")
 }
 
 func builderBedrockClaude3Haiku(t *testing.T, r *recorder.Recorder) (fantasy.LanguageModel, error) {
@@ -52,7 +52,7 @@ func builderBedrockClaude3Haiku(t *testing.T, r *recorder.Recorder) (fantasy.Lan
 	if err != nil {
 		return nil, err
 	}
-	return provider.LanguageModel(t.Context(), "us.anthropic.claude-3-haiku-20240307-v1:0")
+	return provider.LanguageModel(t.Context(), "anthropic.claude-3-haiku-20240307-v1:0")
 }
 
 func buildersBedrockBasicAuth(t *testing.T, r *recorder.Recorder) (fantasy.LanguageModel, error) {
@@ -64,5 +64,5 @@ func buildersBedrockBasicAuth(t *testing.T, r *recorder.Recorder) (fantasy.Langu
 	if err != nil {
 		return nil, err
 	}
-	return provider.LanguageModel(t.Context(), "us.anthropic.claude-3-sonnet-20240229-v1:0")
+	return provider.LanguageModel(t.Context(), "anthropic.claude-3-sonnet-20240229-v1:0")
 }