diff --git a/.changelog/ab122d50fa92409c93e6ba4d5cbcbf28.json b/.changelog/ab122d50fa92409c93e6ba4d5cbcbf28.json
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@@ -0,0 +1,377 @@
+{
+    "id": "ab122d50-fa92-409c-93e6-ba4d5cbcbf28",
+    "type": "bugfix",
+    "description": "Adds case-insensitive handling of error message fields in service responses",
+    "modules": [
+        "internal/protocoltest/awsrestjson",
+        "internal/protocoltest/jsonrpc",
+        "internal/protocoltest/jsonrpc10",
+        "service/accessanalyzer",
+        "service/account",
+        "service/acm",
+        "service/acmpca",
+        "service/amp",
+        "service/amplify",
+        "service/amplifybackend",
+        "service/amplifyuibuilder",
+        "service/apigateway",
+        "service/apigatewaymanagementapi",
+        "service/apigatewayv2",
+        "service/appconfig",
+        "service/appconfigdata",
+        "service/appfabric",
+        "service/appflow",
+        "service/appintegrations",
+        "service/applicationautoscaling",
+        "service/applicationcostprofiler",
+        "service/applicationdiscoveryservice",
+        "service/applicationinsights",
+        "service/applicationsignals",
+        "service/appmesh",
+        "service/apprunner",
+        "service/appstream",
+        "service/appsync",
+        "service/apptest",
+        "service/arczonalshift",
+        "service/artifact",
+        "service/athena",
+        "service/auditmanager",
+        "service/autoscalingplans",
+        "service/b2bi",
+        "service/backup",
+        "service/backupgateway",
+        "service/batch",
+        "service/bcmdataexports",
+        "service/bedrock",
+        "service/bedrockagent",
+        "service/bedrockagentruntime",
+        "service/bedrockruntime",
+        "service/billingconductor",
+        "service/braket",
+        "service/budgets",
+        "service/chatbot",
+        "service/chime",
+        "service/chimesdkidentity",
+        "service/chimesdkmediapipelines",
+        "service/chimesdkmeetings",
+        "service/chimesdkmessaging",
+        "service/chimesdkvoice",
+        "service/cleanrooms",
+        "service/cleanroomsml",
+        "service/cloud9",
+        "service/cloudcontrol",
+        "service/clouddirectory",
+        "service/cloudfrontkeyvaluestore",
+        "service/cloudhsm",
+        "service/cloudhsmv2",
+        "service/cloudsearchdomain",
+        "service/cloudtrail",
+        "service/cloudtraildata",
+        "service/cloudwatchevents",
+        "service/cloudwatchlogs",
+        "service/codeartifact",
+        "service/codebuild",
+        "service/codecatalyst",
+        "service/codecommit",
+        "service/codeconnections",
+        "service/codedeploy",
+        "service/codeguruprofiler",
+        "service/codegurureviewer",
+        "service/codegurusecurity",
+        "service/codepipeline",
+        "service/codestarconnections",
+        "service/codestarnotifications",
+        "service/cognitoidentity",
+        "service/cognitoidentityprovider",
+        "service/cognitosync",
+        "service/comprehend",
+        "service/comprehendmedical",
+        "service/computeoptimizer",
+        "service/configservice",
+        "service/connect",
+        "service/connectcampaigns",
+        "service/connectcases",
+        "service/connectcontactlens",
+        "service/connectparticipant",
+        "service/controlcatalog",
+        "service/controltower",
+        "service/costandusagereportservice",
+        "service/costexplorer",
+        "service/costoptimizationhub",
+        "service/customerprofiles",
+        "service/databasemigrationservice",
+        "service/databrew",
+        "service/dataexchange",
+        "service/datapipeline",
+        "service/datasync",
+        "service/datazone",
+        "service/dax",
+        "service/deadline",
+        "service/detective",
+        "service/devicefarm",
+        "service/devopsguru",
+        "service/directconnect",
+        "service/directoryservice",
+        "service/directoryservicedata",
+        "service/dlm",
+        "service/docdbelastic",
+        "service/drs",
+        "service/dynamodb",
+        "service/dynamodbstreams",
+        "service/ebs",
+        "service/ec2instanceconnect",
+        "service/ecr",
+        "service/ecrpublic",
+        "service/ecs",
+        "service/efs",
+        "service/eks",
+        "service/eksauth",
+        "service/elasticinference",
+        "service/elasticsearchservice",
+        "service/elastictranscoder",
+        "service/emr",
+        "service/emrcontainers",
+        "service/emrserverless",
+        "service/entityresolution",
+        "service/eventbridge",
+        "service/evidently",
+        "service/finspace",
+        "service/finspacedata",
+        "service/firehose",
+        "service/fis",
+        "service/fms",
+        "service/forecast",
+        "service/forecastquery",
+        "service/frauddetector",
+        "service/freetier",
+        "service/fsx",
+        "service/gamelift",
+        "service/geomaps",
+        "service/geoplaces",
+        "service/georoutes",
+        "service/glacier",
+        "service/globalaccelerator",
+        "service/glue",
+        "service/grafana",
+        "service/greengrass",
+        "service/greengrassv2",
+        "service/groundstation",
+        "service/guardduty",
+        "service/health",
+        "service/healthlake",
+        "service/identitystore",
+        "service/imagebuilder",
+        "service/inspector",
+        "service/inspector2",
+        "service/inspectorscan",
+        "service/internetmonitor",
+        "service/iot",
+        "service/iot1clickdevicesservice",
+        "service/iot1clickprojects",
+        "service/iotanalytics",
+        "service/iotdataplane",
+        "service/iotdeviceadvisor",
+        "service/iotevents",
+        "service/ioteventsdata",
+        "service/iotfleethub",
+        "service/iotfleetwise",
+        "service/iotjobsdataplane",
+        "service/iotsecuretunneling",
+        "service/iotsitewise",
+        "service/iotthingsgraph",
+        "service/iottwinmaker",
+        "service/iotwireless",
+        "service/ivs",
+        "service/ivschat",
+        "service/ivsrealtime",
+        "service/kafka",
+        "service/kafkaconnect",
+        "service/kendra",
+        "service/kendraranking",
+        "service/keyspaces",
+        "service/kinesis",
+        "service/kinesisanalytics",
+        "service/kinesisanalyticsv2",
+        "service/kinesisvideo",
+        "service/kinesisvideoarchivedmedia",
+        "service/kinesisvideomedia",
+        "service/kinesisvideosignaling",
+        "service/kinesisvideowebrtcstorage",
+        "service/kms",
+        "service/lakeformation",
+        "service/lambda",
+        "service/launchwizard",
+        "service/lexmodelbuildingservice",
+        "service/lexmodelsv2",
+        "service/lexruntimeservice",
+        "service/lexruntimev2",
+        "service/licensemanager",
+        "service/licensemanagerlinuxsubscriptions",
+        "service/licensemanagerusersubscriptions",
+        "service/lightsail",
+        "service/location",
+        "service/lookoutequipment",
+        "service/lookoutmetrics",
+        "service/lookoutvision",
+        "service/m2",
+        "service/machinelearning",
+        "service/macie2",
+        "service/mailmanager",
+        "service/managedblockchain",
+        "service/managedblockchainquery",
+        "service/marketplaceagreement",
+        "service/marketplacecatalog",
+        "service/marketplacecommerceanalytics",
+        "service/marketplacedeployment",
+        "service/marketplaceentitlementservice",
+        "service/marketplacemetering",
+        "service/marketplacereporting",
+        "service/mediaconnect",
+        "service/mediaconvert",
+        "service/medialive",
+        "service/mediapackage",
+        "service/mediapackagev2",
+        "service/mediapackagevod",
+        "service/mediastore",
+        "service/mediastoredata",
+        "service/mediatailor",
+        "service/medicalimaging",
+        "service/memorydb",
+        "service/mgn",
+        "service/migrationhub",
+        "service/migrationhubconfig",
+        "service/migrationhuborchestrator",
+        "service/migrationhubrefactorspaces",
+        "service/migrationhubstrategy",
+        "service/mq",
+        "service/mturk",
+        "service/mwaa",
+        "service/neptunedata",
+        "service/neptunegraph",
+        "service/networkfirewall",
+        "service/networkmanager",
+        "service/networkmonitor",
+        "service/oam",
+        "service/omics",
+        "service/opensearch",
+        "service/opensearchserverless",
+        "service/opsworks",
+        "service/opsworkscm",
+        "service/organizations",
+        "service/osis",
+        "service/outposts",
+        "service/panorama",
+        "service/paymentcryptography",
+        "service/paymentcryptographydata",
+        "service/pcaconnectorad",
+        "service/pcaconnectorscep",
+        "service/pcs",
+        "service/personalize",
+        "service/personalizeevents",
+        "service/personalizeruntime",
+        "service/pi",
+        "service/pinpoint",
+        "service/pinpointemail",
+        "service/pinpointsmsvoice",
+        "service/pinpointsmsvoicev2",
+        "service/pipes",
+        "service/polly",
+        "service/pricing",
+        "service/privatenetworks",
+        "service/proton",
+        "service/qapps",
+        "service/qbusiness",
+        "service/qconnect",
+        "service/qldb",
+        "service/qldbsession",
+        "service/quicksight",
+        "service/ram",
+        "service/rbin",
+        "service/rdsdata",
+        "service/redshiftdata",
+        "service/redshiftserverless",
+        "service/rekognition",
+        "service/repostspace",
+        "service/resiliencehub",
+        "service/resourceexplorer2",
+        "service/resourcegroups",
+        "service/resourcegroupstaggingapi",
+        "service/robomaker",
+        "service/rolesanywhere",
+        "service/route53domains",
+        "service/route53profiles",
+        "service/route53recoverycluster",
+        "service/route53recoverycontrolconfig",
+        "service/route53recoveryreadiness",
+        "service/route53resolver",
+        "service/rum",
+        "service/s3outposts",
+        "service/sagemaker",
+        "service/sagemakera2iruntime",
+        "service/sagemakeredge",
+        "service/sagemakerfeaturestoreruntime",
+        "service/sagemakergeospatial",
+        "service/sagemakerruntime",
+        "service/savingsplans",
+        "service/scheduler",
+        "service/schemas",
+        "service/secretsmanager",
+        "service/securityhub",
+        "service/securitylake",
+        "service/serverlessapplicationrepository",
+        "service/servicecatalog",
+        "service/servicecatalogappregistry",
+        "service/servicediscovery",
+        "service/servicequotas",
+        "service/sesv2",
+        "service/sfn",
+        "service/shield",
+        "service/signer",
+        "service/simspaceweaver",
+        "service/sms",
+        "service/snowball",
+        "service/snowdevicemanagement",
+        "service/socialmessaging",
+        "service/sqs",
+        "service/ssm",
+        "service/ssmcontacts",
+        "service/ssmincidents",
+        "service/ssmquicksetup",
+        "service/ssmsap",
+        "service/sso",
+        "service/ssoadmin",
+        "service/ssooidc",
+        "service/storagegateway",
+        "service/supplychain",
+        "service/support",
+        "service/supportapp",
+        "service/swf",
+        "service/synthetics",
+        "service/taxsettings",
+        "service/textract",
+        "service/timestreaminfluxdb",
+        "service/timestreamquery",
+        "service/timestreamwrite",
+        "service/tnb",
+        "service/transcribe",
+        "service/transcribestreaming",
+        "service/transfer",
+        "service/translate",
+        "service/trustedadvisor",
+        "service/verifiedpermissions",
+        "service/voiceid",
+        "service/vpclattice",
+        "service/waf",
+        "service/wafregional",
+        "service/wafv2",
+        "service/wellarchitected",
+        "service/wisdom",
+        "service/workdocs",
+        "service/workmail",
+        "service/workmailmessageflow",
+        "service/workspaces",
+        "service/workspacesthinclient",
+        "service/workspacesweb",
+        "service/xray"
+    ]
+}
\ No newline at end of file