Update default model to be Claude 4 Sonnet (strands-agents#467)

Co-authored-by: Mackenzie Zastrow <[email protected]>

Author: zastrowm

README.md

@@ -55,7 +55,7 @@ agent = Agent(tools=[calculator])
 agent("What is the square root of 1764")
 ```
 
-> **Note**: For the default Amazon Bedrock model provider, you'll need AWS credentials configured and model access enabled for Claude 3.7 Sonnet in the us-west-2 region. See the [Quickstart Guide](https://strandsagents.com/) for details on configuring other model providers.
+> **Note**: For the default Amazon Bedrock model provider, you'll need AWS credentials configured and model access enabled for Claude 4 Sonnet in the us-west-2 region. See the [Quickstart Guide](https://strandsagents.com/) for details on configuring other model providers.
 
 ## Installation
 

src/strands/models/bedrock.py

@@ -25,7 +25,7 @@
 
 logger = logging.getLogger(__name__)
 
-DEFAULT_BEDROCK_MODEL_ID = "us.anthropic.claude-3-7-sonnet-20250219-v1:0"
+DEFAULT_BEDROCK_MODEL_ID = "us.anthropic.claude-sonnet-4-20250514-v1:0"
 DEFAULT_BEDROCK_REGION = "us-west-2"
 
 BEDROCK_CONTEXT_WINDOW_OVERFLOW_MESSAGES = [
@@ -67,7 +67,7 @@ class BedrockConfig(TypedDict, total=False):
             guardrail_redact_output: Flag to redact output if guardrail is triggered. Defaults to False.
             guardrail_redact_output_message: If a Bedrock Output guardrail triggers, replace output with this message.
             max_tokens: Maximum number of tokens to generate in the response
-            model_id: The Bedrock model ID (e.g., "us.anthropic.claude-3-7-sonnet-20250219-v1:0")
+            model_id: The Bedrock model ID (e.g., "us.anthropic.claude-sonnet-4-20250514-v1:0")
             stop_sequences: List of sequences that will stop generation when encountered
             streaming: Flag to enable/disable streaming. Defaults to True.
             temperature: Controls randomness in generation (higher = more random)
@@ -432,7 +432,7 @@ def _stream(
                 ):
                     e.add_note(
                         "└ For more information see "
-                        "https://strandsagents.com/user-guide/concepts/model-providers/amazon-bedrock/#model-access-issue"
+                        "https://strandsagents.com/latest/user-guide/concepts/model-providers/amazon-bedrock/#model-access-issue"
                     )
 
                 if (

tests/strands/models/test_bedrock.py

@@ -1148,7 +1148,7 @@ async def test_add_note_on_access_denied_exception(bedrock_client, model, alist)
         "└ Bedrock region: us-west-2",
         "└ Model id: m1",
         "└ For more information see "
-        "https://strandsagents.com/user-guide/concepts/model-providers/amazon-bedrock/#model-access-issue",
+        "https://strandsagents.com/latest/user-guide/concepts/model-providers/amazon-bedrock/#model-access-issue",
     ]