bedrockagent: gate tests which depend on Amazon Titan foundation models

```console
% make t K=bedrockagent T=TestAccBedrockAgent_serial/DataSource
make: Verifying source code with gofmt...
==> Checking that code complies with gofmt requirements...
make: Running acceptance tests on branch: 🌿 td-bedrock-nova 🌿...
TF_ACC=1 go1.26.2 test ./internal/service/bedrockagent/... -v -count 1 -parallel 20 -run='TestAccBedrockAgent_serial/DataSource'  -timeout 360m -vet=off
2026/05/08 15:06:01 Creating Terraform AWS Provider (SDKv2-style)...
2026/05/08 15:06:01 Initializing Terraform AWS Provider (SDKv2-style)...
=== RUN   TestAccBedrockAgent_serial
=== PAUSE TestAccBedrockAgent_serial
=== CONT  TestAccBedrockAgent_serial
=== RUN   TestAccBedrockAgent_serial/DataSource
=== RUN   TestAccBedrockAgent_serial/DataSource/disappears
    data_source_test.go:351: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/update
    data_source_test.go:378: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/hierarchical
    data_source_test.go:148: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/parsingModality
    data_source_test.go:297: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/webConfiguration
    data_source_test.go:439: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/basic
    data_source_test.go:21: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/full
    data_source_test.go:51: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/semantic
    data_source_test.go:99: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/parsing
    data_source_test.go:246: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/bedrockDataAutomation
    data_source_test.go:483: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
=== RUN   TestAccBedrockAgent_serial/DataSource/customTransformation
    data_source_test.go:198: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
--- PASS: TestAccBedrockAgent_serial (0.00s)
    --- PASS: TestAccBedrockAgent_serial/DataSource (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/disappears (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/update (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/hierarchical (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/parsingModality (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/webConfiguration (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/basic (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/full (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/semantic (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/parsing (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/bedrockDataAutomation (0.00s)
        --- SKIP: TestAccBedrockAgent_serial/DataSource/customTransformation (0.00s)
PASS
ok      github.com/hashicorp/terraform-provider-aws/internal/service/bedrockagent       7.017s
```

```console
% make t K=bedrockagent T=TestAccBedrockAgentAgentKnowledgeBaseAssociation_
make: Verifying source code with gofmt...
==> Checking that code complies with gofmt requirements...
make: Running acceptance tests on branch: 🌿 td-bedrock-nova 🌿...
TF_ACC=1 go1.26.2 test ./internal/service/bedrockagent/... -v -count 1 -parallel 20 -run='TestAccBedrockAgentAgentKnowledgeBaseAssociation_'  -timeout 360m -vet=off
2026/05/08 15:09:04 Creating Terraform AWS Provider (SDKv2-style)...
2026/05/08 15:09:04 Initializing Terraform AWS Provider (SDKv2-style)...
=== RUN   TestAccBedrockAgentAgentKnowledgeBaseAssociation_basic
    agent_knowledge_base_association_test.go:21: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
--- SKIP: TestAccBedrockAgentAgentKnowledgeBaseAssociation_basic (0.00s)
=== RUN   TestAccBedrockAgentAgentKnowledgeBaseAssociation_update
    agent_knowledge_base_association_test.go:54: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
--- SKIP: TestAccBedrockAgentAgentKnowledgeBaseAssociation_update (0.00s)
=== RUN   TestAccBedrockAgentAgentKnowledgeBaseAssociation_disappears
    agent_knowledge_base_association_test.go:95: skipping test; environment variable TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED must be set
--- SKIP: TestAccBedrockAgentAgentKnowledgeBaseAssociation_disappears (0.00s)
PASS
ok      github.com/hashicorp/terraform-provider-aws/internal/service/bedrockagent       7.047s
```

Not all acceptance tests for the knowledge base resource depend on an
Amazon Titan model, and therefore only a portion will be skipped under
the newly added conditions.

Author: jar-b

docs/acc-test-environment-variables.md

@@ -112,6 +112,7 @@ Environment variables (beyond standard AWS Go SDK ones) used by acceptance testi
 | `TF_ACC_ASSUME_ROLE_ARN`                                        | Amazon Resource Name of existing IAM Role to use for limited permissions acceptance testing.                                                                                                     |
 | `TF_ACC_REQUIRED_TAG_KEY`                                       | Name of the tag key required for the resource being tested as defined in the organizational tagging policy                                                                                       |
 | `TF_AWS_BEDROCK_OSS_COLLECTION_NAME`                            | Name of the OpenSearch Serverless collection to be used with an Amazon Bedrock Knowledge Base.                                                                                                   |
+| `TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED`                            | Flag to enable tests which require use of Amazon Titan foundation models. Set to `1` to run tests.                                                                                                    |
 | `TF_AWS_CONTROLTOWER_CONTROL_OU_NAME`                           | Organizational unit name to be targeted by the Control Tower control.                                                                                                                            |
 | `TF_AWS_CONTROLTOWER_BASELINE_ENABLE_BASELINE_ARN`              | Enable baseline ARN.                                                                                                                                                                             |
 | `TF_AWS_DATAEXCHANGE_DATA_SET_ID`                               | ID of DataExchange Data Set to use for testing.                                                                                                                                                  |

internal/service/bedrockagent/agent_knowledge_base_association_test.go

@@ -18,6 +18,8 @@ import (
 )
 
 func TestAccBedrockAgentAgentKnowledgeBaseAssociation_basic(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var agentknowledgebaseassociation types.AgentKnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -49,6 +51,8 @@ func TestAccBedrockAgentAgentKnowledgeBaseAssociation_basic(t *testing.T) {
 }
 
 func TestAccBedrockAgentAgentKnowledgeBaseAssociation_update(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var agentknowledgebaseassociation types.AgentKnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -88,6 +92,8 @@ func TestAccBedrockAgentAgentKnowledgeBaseAssociation_update(t *testing.T) {
 }
 
 func TestAccBedrockAgentAgentKnowledgeBaseAssociation_disappears(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var agentknowledgebaseassociation types.AgentKnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)

internal/service/bedrockagent/data_source_test.go

@@ -18,6 +18,8 @@ import (
 )
 
 func testAccDataSource_basic(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -46,6 +48,8 @@ func testAccDataSource_basic(t *testing.T) {
 }
 
 func testAccDataSource_full(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -92,6 +96,8 @@ func testAccDataSource_full(t *testing.T) {
 }
 
 func testAccDataSource_fullSemantic(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -139,6 +145,8 @@ func testAccDataSource_fullSemantic(t *testing.T) {
 }
 
 func testAccDataSource_fullHierarchical(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -187,6 +195,8 @@ func testAccDataSource_fullHierarchical(t *testing.T) {
 }
 
 func testAccDataSource_fullCustomTranformation(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -233,6 +243,8 @@ func testAccDataSource_fullCustomTranformation(t *testing.T) {
 }
 
 func testAccDataSource_parsing(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -282,6 +294,8 @@ func testAccDataSource_parsing(t *testing.T) {
 }
 
 func testAccDataSource_parsingModality(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -334,6 +348,8 @@ func testAccDataSource_parsingModality(t *testing.T) {
 }
 
 func testAccDataSource_disappears(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -359,6 +375,8 @@ func testAccDataSource_disappears(t *testing.T) {
 }
 
 func testAccDataSource_update(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -418,6 +436,8 @@ func testAccDataSource_update(t *testing.T) {
 }
 
 func testAccDataSource_webConfiguration(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	if testing.Short() {
 		t.Skip("skipping long-running test in short mode")
@@ -460,6 +480,8 @@ func testAccDataSource_bedrockDataAutomation(t *testing.T) {
 	acctest.SkipIfExeNotOnPath(t, "jq")
 	acctest.SkipIfExeNotOnPath(t, "aws")
 
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var dataSource types.DataSource
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)

internal/service/bedrockagent/knowledge_base_test.go

@@ -22,7 +22,21 @@ import (
 	"github.com/hashicorp/terraform-provider-aws/names"
 )
 
+// TitanModelsAllowedEnvVar is the environment variable which
+// must be set to run acceptance tests relying on Amazon Titan embedded text
+// models.
+//
+// These models are not currently approved for use in the main HashiCorp
+// test account, and therefore tests depending on these models are skipped
+// by default.
+//
+// See the full list of supported models in the Amazon Bedrock documentation:
+// https://docs.aws.amazon.com/bedrock/latest/userguide/knowledge-base-supported.html#knowledge-base-supported-embeddings
+const TitanModelsAllowedEnvVar = "TF_AWS_BEDROCK_TITAN_MODELS_ALLOWED"
+
 func testAccKnowledgeBase_disappears(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var knowledgebase awstypes.KnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -56,6 +70,8 @@ func testAccKnowledgeBase_disappears(t *testing.T) {
 }
 
 func testAccKnowledgeBase_tags(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var knowledgebase awstypes.KnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -134,6 +150,8 @@ func testAccKnowledgeBase_RDS_basic(t *testing.T) {
 	acctest.SkipIfExeNotOnPath(t, "jq")
 	acctest.SkipIfExeNotOnPath(t, "aws")
 
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var knowledgebase awstypes.KnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -198,6 +216,8 @@ func testAccKnowledgeBase_RDS_basic(t *testing.T) {
 }
 
 func testAccKnowledgeBase_OpenSearchServerless_basic(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	collectionName := skipIfOSSCollectionNameEnvVarNotSet(t)
 	var knowledgebase awstypes.KnowledgeBase
@@ -255,6 +275,8 @@ func testAccKnowledgeBase_OpenSearchServerless_basic(t *testing.T) {
 }
 
 func testAccKnowledgeBase_update(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var knowledgebase awstypes.KnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -313,6 +335,8 @@ func testAccKnowledgeBase_RDS_supplementalDataStorage(t *testing.T) {
 	acctest.SkipIfExeNotOnPath(t, "jq")
 	acctest.SkipIfExeNotOnPath(t, "aws")
 
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var knowledgebase awstypes.KnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -417,6 +441,8 @@ func testAccKnowledgeBase_Kendra_basic(t *testing.T) {
 }
 
 func testAccKnowledgeBase_OpenSearchManagedCluster_basic(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var knowledgebase awstypes.KnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)
@@ -477,6 +503,8 @@ func testAccKnowledgeBase_OpenSearchManagedCluster_basic(t *testing.T) {
 }
 
 func testAccKnowledgeBase_S3Vectors_update(t *testing.T) {
+	acctest.SkipIfEnvVarNotSet(t, TitanModelsAllowedEnvVar)
+
 	ctx := acctest.Context(t)
 	var knowledgebase awstypes.KnowledgeBase
 	rName := acctest.RandomWithPrefix(t, acctest.ResourcePrefix)