# Update a configuration bundle
<a name="configuration-bundles-update"></a>

Update a configuration bundle to create a new immutable version with changed configuration. Each update produces a new version ID; existing versions are never modified. Versions form a chain via `parentVersionIds`, similar to git commits.

## Code samples
<a name="update-bundle-examples"></a>

**Example**  
Edit the configuration in `agentcore.json` and redeploy. The CLI detects the existing bundle and creates a new version with the correct `parentVersionIds` automatically:  

```
# Edit the bundle configuration in agentcore.json (change model_id, system prompt, etc.)
# Then redeploy to create a new version:
agentcore deploy
```
Update changing the model ID:  

```
import boto3
import uuid

client = boto3.client("bedrock-agentcore-control", region_name="us-west-2")

RUNTIME_ARN = "arn:aws:bedrock-agentcore:us-west-2:123456789012:runtime/MyAgent-abc123"

response = client.update_configuration_bundle(
    bundleId="myAgentConfig-a1b2c3d4e5",
    components={
        RUNTIME_ARN: {
            "configuration": {
                "system_prompt": "You are a helpful customer support assistant.",
                "model_id": "us.anthropic.claude-sonnet-4-20250514-v1:0",
                "temperature": 0.7,
            }
        }
    },
    parentVersionIds=["12345678-1234-1234-1234-123456789012"],
    commitMessage="Switch to Claude Sonnet 4",
    clientToken=str(uuid.uuid4()),
)

print(f"New version ID: {response['versionId']}")
```
Update with a recommended system prompt from a recommendation result:  

```
import boto3
import uuid

cp_client = boto3.client("bedrock-agentcore-control", region_name="us-west-2")
dp_client = boto3.client("bedrock-agentcore", region_name="us-west-2")

RUNTIME_ARN = "arn:aws:bedrock-agentcore:us-west-2:123456789012:runtime/MyAgent-abc123"

# Get the recommendation result
recommendation = dp_client.get_recommendation(recommendationId="myRec-a1b2c3d4e5")
recommended_prompt = recommendation["result"]["systemPromptRecommendationResult"]["recommendedSystemPrompt"]

# Update the bundle with the recommended prompt
response = cp_client.update_configuration_bundle(
    bundleId="myAgentConfig-a1b2c3d4e5",
    components={
        RUNTIME_ARN: {
            "configuration": {
                "system_prompt": recommended_prompt,
                "model_id": "global.anthropic.claude-sonnet-4-5-20250929-v1:0",
                "temperature": 0.7,
            }
        }
    },
    parentVersionIds=["12345678-1234-1234-1234-123456789012"],
    commitMessage="Apply recommended system prompt",
    createdBy={"name": "optimization-job", "arn": recommendation["recommendationArn"]},
    clientToken=str(uuid.uuid4()),
)

print(f"New version ID: {response['versionId']}")
```

## Request parameters
<a name="update-bundle-params"></a>


| Parameter | Type | Required | Description | 
| --- | --- | --- | --- | 
|  `bundleId`  | String | Yes | The ID of the configuration bundle to update. Passed as a path parameter. | 
|  `bundleName`  | String | No | Updated name for the bundle. | 
|  `description`  | String | No | Updated description. Maximum 500 characters. | 
|  `components`  | Map | No | Updated component configurations. Creates a new version with these components. | 
|  `parentVersionIds`  | List of strings | No | Parent version IDs for lineage tracking. **Required when updating `components`.** Regular commits: single parent. Merge commits: two parents (target branch latest, source branch latest). If the branch already exists, the first parent must be the latest version on that branch. | 
|  `branchName`  | String | No | Branch name for this version. If not specified, inherits the parent’s branch or defaults to `mainline`. | 
|  `commitMessage`  | String | No | Commit message describing the changes. Maximum 500 characters. | 
|  `createdBy`  | Object | No | Source that created this version. Contains `name` (required) and `arn` (optional). Use this to track whether a version was created by a user, recommendation job, or other automation. | 
|  `clientToken`  | String | No | Idempotency token. | 

## Response
<a name="update-bundle-response"></a>


| Field | Type | Description | 
| --- | --- | --- | 
|  `bundleArn`  | String | ARN of the configuration bundle. | 
|  `bundleId`  | String | ID of the configuration bundle. | 
|  `versionId`  | String | UUID of the new version created by this update. | 
|  `updatedAt`  | Timestamp | When the update was applied. | 

## Branching and merges
<a name="update-bundle-branching"></a>

Configuration bundles support git-like branching:
+  **Linear commits.** Omit `parentVersionIds` or pass a single parent. The new version extends the branch lineage.
+  **New branch.** Specify a `branchName` that does not yet exist and a `parentVersionIds` pointing to the version you want to branch from.
+  **Merge commits.** Pass two `parentVersionIds`: the first is the latest version on the target branch, the second is the latest on the source branch. This creates a merge commit on the target branch.

## Errors
<a name="update-bundle-errors"></a>


| Error | HTTP status | Description | 
| --- | --- | --- | 
|  `ValidationException`  | 400 | Invalid request parameters. Check field constraints. | 
|  `ResourceNotFoundException`  | 404 | The specified `bundleId` does not exist. | 
|  `ConflictException`  | 409 | Version conflict. The specified parent version is not the latest on the branch. Fetch the latest version and retry. | 
|  `AccessDeniedException`  | 403 | Insufficient permissions. Verify IAM policies include `bedrock-agentcore:UpdateConfigurationBundle`. | 
|  `ThrottlingException`  | 429 | Request rate exceeded. Retry with exponential backoff. | 
|  `InternalServerException`  | 500 | Service-side error. Retry the request. |