diff --git a/packages/core/src/submodules/account-id-endpoint/AccountIdEndpointModeConfigResolver.ts b/packages/core/src/submodules/account-id-endpoint/AccountIdEndpointModeConfigResolver.ts
index b9166c184c39e..e07c3dd3e4f05 100644
--- a/packages/core/src/submodules/account-id-endpoint/AccountIdEndpointModeConfigResolver.ts
+++ b/packages/core/src/submodules/account-id-endpoint/AccountIdEndpointModeConfigResolver.ts
@@ -1,4 +1,4 @@
-import { Provider } from "@smithy/types";
+import type { Provider } from "@smithy/types";
 import { normalizeProvider } from "@smithy/util-middleware";
 
 import {
diff --git a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/AwsSdkSigV4ASigner.ts b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/AwsSdkSigV4ASigner.ts
index 097a06e6ecfe0..ba3ba9e30186a 100644
--- a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/AwsSdkSigV4ASigner.ts
+++ b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/AwsSdkSigV4ASigner.ts
@@ -1,5 +1,5 @@
 import { HttpRequest } from "@smithy/protocol-http";
-import { AwsCredentialIdentity, HttpRequest as IHttpRequest } from "@smithy/types";
+import type { AwsCredentialIdentity, HttpRequest as IHttpRequest } from "@smithy/types";
 
 import { getSkewCorrectedDate } from "../utils";
 import { AwsSdkSigV4Signer, validateSigningProperties } from "./AwsSdkSigV4Signer";
diff --git a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/AwsSdkSigV4Signer.ts b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/AwsSdkSigV4Signer.ts
index acda615969c51..eb11b5a952f37 100644
--- a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/AwsSdkSigV4Signer.ts
+++ b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/AwsSdkSigV4Signer.ts
@@ -1,6 +1,6 @@
 import { HttpRequest } from "@smithy/protocol-http";
 import { ServiceException } from "@smithy/smithy-client";
-import {
+import type {
   AuthScheme,
   AwsCredentialIdentity,
   HandlerExecutionContext,
diff --git a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4AConfig.ts b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4AConfig.ts
index ab7eee8424c96..0e27328bd914b 100644
--- a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4AConfig.ts
+++ b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4AConfig.ts
@@ -1,7 +1,7 @@
 import { normalizeProvider } from "@smithy/core";
 import { LoadedConfigSelectors } from "@smithy/node-config-provider";
 import { ProviderError } from "@smithy/property-provider";
-import { Profile, Provider } from "@smithy/types";
+import type { Profile, Provider } from "@smithy/types";
 
 /**
  * @public
diff --git a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4Config.spec.ts b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4Config.spec.ts
index 0075c41684c55..0d59d1a109bd9 100644
--- a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4Config.spec.ts
+++ b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4Config.spec.ts
@@ -1,4 +1,4 @@
-import { AwsCredentialIdentityProvider, IdentityProvider } from "@smithy/types";
+import type { AwsCredentialIdentityProvider } from "@smithy/types";
 import { describe, expect, test as it, vi } from "vitest";
 
 import { resolveAwsSdkSigV4Config } from "./resolveAwsSdkSigV4Config";
diff --git a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4Config.ts b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4Config.ts
index 34536efe0932c..8e4b89c4eb0cb 100644
--- a/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4Config.ts
+++ b/packages/core/src/submodules/httpAuthSchemes/aws_sdk/resolveAwsSdkSigV4Config.ts
@@ -7,7 +7,7 @@ import {
   normalizeProvider,
 } from "@smithy/core";
 import { SignatureV4, SignatureV4CryptoInit, SignatureV4Init } from "@smithy/signature-v4";
-import {
+import type {
   AuthScheme,
   AwsCredentialIdentity,
   AwsCredentialIdentityProvider,
diff --git a/packages/core/src/submodules/protocols/ConfigurableSerdeContext.ts b/packages/core/src/submodules/protocols/ConfigurableSerdeContext.ts
index af2ba0fc84a1d..dd0febd6910d1 100644
--- a/packages/core/src/submodules/protocols/ConfigurableSerdeContext.ts
+++ b/packages/core/src/submodules/protocols/ConfigurableSerdeContext.ts
@@ -1,4 +1,4 @@
-import { ConfigurableSerdeContext, SerdeFunctions } from "@smithy/types";
+import type { ConfigurableSerdeContext, SerdeFunctions } from "@smithy/types";
 
 /**
  * @internal
diff --git a/packages/core/src/submodules/protocols/cbor/AwsSmithyRpcV2CborProtocol.spec.ts b/packages/core/src/submodules/protocols/cbor/AwsSmithyRpcV2CborProtocol.spec.ts
index 646806059cbdb..fe6f83976e41e 100644
--- a/packages/core/src/submodules/protocols/cbor/AwsSmithyRpcV2CborProtocol.spec.ts
+++ b/packages/core/src/submodules/protocols/cbor/AwsSmithyRpcV2CborProtocol.spec.ts
@@ -1,7 +1,8 @@
 import { cbor } from "@smithy/core/cbor";
-import { op, SCHEMA } from "@smithy/core/schema";
+import { op } from "@smithy/core/schema";
 import { error as registerError } from "@smithy/core/schema";
 import { HttpResponse } from "@smithy/protocol-http";
+import type { NumericSchema, StringSchema } from "@smithy/types";
 import { describe, expect, test as it } from "vitest";
 
 import { AwsSmithyRpcV2CborProtocol } from "./AwsSmithyRpcV2CborProtocol";
@@ -20,7 +21,7 @@ describe(AwsSmithyRpcV2CborProtocol.name, () => {
       "MyQueryError",
       { error: "client" },
       ["Message", "Prop2"],
-      [SCHEMA.STRING, SCHEMA.NUMERIC],
+      [0 satisfies StringSchema, 1 satisfies NumericSchema],
       MyQueryError
     );
 
diff --git a/packages/core/src/submodules/protocols/json/AwsJson1_0Protocol.spec.ts b/packages/core/src/submodules/protocols/json/AwsJson1_0Protocol.spec.ts
index 16d7c227bba55..ae9e63ee67d75 100644
--- a/packages/core/src/submodules/protocols/json/AwsJson1_0Protocol.spec.ts
+++ b/packages/core/src/submodules/protocols/json/AwsJson1_0Protocol.spec.ts
@@ -1,4 +1,12 @@
-import { map, op, SCHEMA, sim, struct } from "@smithy/core/schema";
+import { map, op, sim, struct } from "@smithy/core/schema";
+import type {
+  BlobSchema,
+  BooleanSchema,
+  DocumentSchema,
+  NumericSchema,
+  StringSchema,
+  TimestampDefaultSchema,
+} from "@smithy/types";
 import { toBase64 } from "@smithy/util-base64";
 import { toUtf8 } from "@smithy/util-utf8";
 import { describe, expect, test as it } from "vitest";
@@ -19,7 +27,13 @@ describe(AwsJson1_0Protocol.name, () => {
     "MyStruct",
     0,
     [...Object.keys(json)],
-    [SCHEMA.STRING, SCHEMA.NUMERIC, SCHEMA.BOOLEAN, SCHEMA.BLOB, SCHEMA.TIMESTAMP_DEFAULT]
+    [
+      0 satisfies StringSchema,
+      1 satisfies NumericSchema,
+      2 satisfies BooleanSchema,
+      21 satisfies BlobSchema,
+      4 satisfies TimestampDefaultSchema,
+    ]
   );
   const serdeContext = {
     base64Encoder: toBase64,
@@ -85,18 +99,18 @@ describe(AwsJson1_0Protocol.name, () => {
         {},
         ["header", "query", "headerMap", "payload"],
         [
-          sim("ns", "MyHeader", SCHEMA.STRING, { httpHeader: "header", jsonName: "MyHeader" }),
-          sim("ns", "MyQuery", SCHEMA.STRING, { httpQuery: "query" }),
+          sim("ns", "MyHeader", 0 satisfies StringSchema, { httpHeader: "header", jsonName: "MyHeader" }),
+          sim("ns", "MyQuery", 0 satisfies StringSchema, { httpQuery: "query" }),
           map(
             "ns",
             "HeaderMap",
             {
               httpPrefixHeaders: "",
             },
-            SCHEMA.STRING,
-            SCHEMA.NUMERIC
+            0 satisfies StringSchema,
+            1 satisfies NumericSchema
           ),
-          sim("ns", "MyPayload", SCHEMA.DOCUMENT, { httpPayload: 1 }),
+          sim("ns", "MyPayload", 15 satisfies DocumentSchema, { httpPayload: 1 }),
         ]
       );
       const operationSchema = op("ns", "MyOperation", {}, schema, "unit");
diff --git a/packages/core/src/submodules/protocols/json/AwsJsonRpcProtocol.spec.ts b/packages/core/src/submodules/protocols/json/AwsJsonRpcProtocol.spec.ts
index 3be2a02d54720..5c62d58b2e8e9 100644
--- a/packages/core/src/submodules/protocols/json/AwsJsonRpcProtocol.spec.ts
+++ b/packages/core/src/submodules/protocols/json/AwsJsonRpcProtocol.spec.ts
@@ -1,5 +1,6 @@
-import { error as registerError, op, SCHEMA } from "@smithy/core/schema";
+import { error as registerError, op } from "@smithy/core/schema";
 import { HttpResponse } from "@smithy/protocol-http";
+import type { NumericSchema, StringSchema, TimestampEpochSecondsSchema } from "@smithy/types";
 import { fromUtf8 } from "@smithy/util-utf8";
 import { describe, expect, test as it } from "vitest";
 
@@ -25,7 +26,7 @@ describe(AwsJsonRpcProtocol.name, () => {
     expect(codec.settings).toEqual({
       jsonName: false,
       timestampFormat: {
-        default: SCHEMA.TIMESTAMP_EPOCH_SECONDS,
+        default: 7 satisfies TimestampEpochSecondsSchema,
         useTrait: true,
       },
     });
@@ -39,7 +40,7 @@ describe(AwsJsonRpcProtocol.name, () => {
       "MyQueryError",
       { error: "client" },
       ["Message", "Prop2"],
-      [SCHEMA.STRING, SCHEMA.NUMERIC],
+      [0 satisfies StringSchema, 1 satisfies NumericSchema],
       MyQueryError
     );
 
diff --git a/packages/core/src/submodules/protocols/json/AwsJsonRpcProtocol.ts b/packages/core/src/submodules/protocols/json/AwsJsonRpcProtocol.ts
index cfbb4b16d8360..5f3c140026b89 100644
--- a/packages/core/src/submodules/protocols/json/AwsJsonRpcProtocol.ts
+++ b/packages/core/src/submodules/protocols/json/AwsJsonRpcProtocol.ts
@@ -1,5 +1,5 @@
 import { RpcProtocol } from "@smithy/core/protocols";
-import { deref, NormalizedSchema, SCHEMA, TypeRegistry } from "@smithy/core/schema";
+import { deref, NormalizedSchema, TypeRegistry } from "@smithy/core/schema";
 import type {
   EndpointBearer,
   HandlerExecutionContext,
@@ -10,6 +10,7 @@ import type {
   SerdeFunctions,
   ShapeDeserializer,
   ShapeSerializer,
+  TimestampEpochSecondsSchema,
 } from "@smithy/types";
 
 import { ProtocolLib } from "../ProtocolLib";
@@ -43,7 +44,7 @@ export abstract class AwsJsonRpcProtocol extends RpcProtocol {
     this.codec = new JsonCodec({
       timestampFormat: {
         useTrait: true,
-        default: SCHEMA.TIMESTAMP_EPOCH_SECONDS,
+        default: 7 as const satisfies TimestampEpochSecondsSchema,
       },
       jsonName: false,
     });
diff --git a/packages/core/src/submodules/protocols/json/AwsRestJsonProtocol.spec.ts b/packages/core/src/submodules/protocols/json/AwsRestJsonProtocol.spec.ts
index ead21b9da5d79..47d5084f4d45e 100644
--- a/packages/core/src/submodules/protocols/json/AwsRestJsonProtocol.spec.ts
+++ b/packages/core/src/submodules/protocols/json/AwsRestJsonProtocol.spec.ts
@@ -1,5 +1,16 @@
-import { op, SCHEMA, sim, struct } from "@smithy/core/schema";
+import { op, sim, struct } from "@smithy/core/schema";
 import { HttpResponse } from "@smithy/protocol-http";
+import type {
+  BlobSchema,
+  BooleanSchema,
+  MapSchemaModifier,
+  NumericSchema,
+  StringSchema,
+  TimestampDateTimeSchema,
+  TimestampDefaultSchema,
+  TimestampEpochSecondsSchema,
+  TimestampHttpDateSchema,
+} from "@smithy/types";
 import { toBase64 } from "@smithy/util-base64";
 import { toUtf8 } from "@smithy/util-utf8";
 import { describe, expect, test as it } from "vitest";
@@ -20,7 +31,13 @@ describe(AwsRestJsonProtocol.name, () => {
     "MyStruct",
     0,
     [...Object.keys(json)],
-    [SCHEMA.STRING, SCHEMA.NUMERIC, SCHEMA.BOOLEAN, SCHEMA.BLOB, SCHEMA.TIMESTAMP_DEFAULT]
+    [
+      0 satisfies StringSchema,
+      1 satisfies NumericSchema,
+      2 satisfies BooleanSchema,
+      21 satisfies BlobSchema,
+      4 satisfies TimestampDefaultSchema,
+    ]
   );
   const serdeContext = {
     base64Encoder: toBase64,
@@ -87,10 +104,10 @@ describe(AwsRestJsonProtocol.name, () => {
         {},
         ["header", "query", "headerMap", "payload"],
         [
-          [SCHEMA.STRING, { httpHeader: "header" }],
-          [SCHEMA.STRING, { httpQuery: "query" }],
+          [0 satisfies StringSchema, { httpHeader: "header" }],
+          [0 satisfies StringSchema, { httpQuery: "query" }],
           [
-            SCHEMA.MAP_MODIFIER | SCHEMA.NUMERIC,
+            (128 satisfies MapSchemaModifier) | (1 satisfies NumericSchema),
             {
               httpPrefixHeaders: "",
             },
@@ -102,8 +119,8 @@ describe(AwsRestJsonProtocol.name, () => {
               0,
               ["a", "b"],
               [
-                [SCHEMA.STRING, 0],
-                [SCHEMA.STRING, { jsonName: "JSON_NAME" }],
+                [0 satisfies StringSchema, 0],
+                [0 satisfies StringSchema, { jsonName: "JSON_NAME" }],
               ]
             ),
             { httpPayload: 1 },
@@ -116,10 +133,10 @@ describe(AwsRestJsonProtocol.name, () => {
         {},
         ["header", "code", "headerMap", "payload"],
         [
-          [SCHEMA.STRING, { httpHeader: "header" }],
-          [SCHEMA.NUMERIC, { httpResponseCode: 1 }],
+          [0 satisfies StringSchema, { httpHeader: "header" }],
+          [1 satisfies NumericSchema, { httpResponseCode: 1 }],
           [
-            SCHEMA.MAP_MODIFIER | SCHEMA.NUMERIC,
+            (128 satisfies MapSchemaModifier) | (1 satisfies NumericSchema),
             {
               httpPrefixHeaders: "x-",
             },
@@ -131,8 +148,8 @@ describe(AwsRestJsonProtocol.name, () => {
               { httpPayload: 1 },
               ["a", "b"],
               [
-                [SCHEMA.STRING, 0],
-                [SCHEMA.STRING, { jsonName: "JSON_NAME" }],
+                [0 satisfies StringSchema, 0],
+                [0 satisfies StringSchema, { jsonName: "JSON_NAME" }],
               ]
             ),
             { httpPayload: 1 },
@@ -230,18 +247,21 @@ describe(AwsRestJsonProtocol.name, () => {
               "payloadDefaultDate",
             ],
             [
-              [SCHEMA.TIMESTAMP_DEFAULT, { httpHeader: "header-default-date" }],
-              [SCHEMA.TIMESTAMP_DATE_TIME, { httpHeader: "header-member-trait-date" }],
-              [SCHEMA.TIMESTAMP_HTTP_DATE, { httpHeader: "header-http-date" }],
-              [SCHEMA.TIMESTAMP_EPOCH_SECONDS, { httpHeader: "header-epoch-seconds" }],
+              [4 satisfies TimestampDefaultSchema, { httpHeader: "header-default-date" }],
+              [5 satisfies TimestampDateTimeSchema, { httpHeader: "header-member-trait-date" }],
+              [6 satisfies TimestampHttpDateSchema, { httpHeader: "header-http-date" }],
+              [7 satisfies TimestampEpochSecondsSchema, { httpHeader: "header-epoch-seconds" }],
               [
-                sim("ns", "", SCHEMA.TIMESTAMP_EPOCH_SECONDS, 0),
+                sim("ns", "", 7 satisfies TimestampEpochSecondsSchema, 0),
                 {
                   httpHeader: "header-target-trait-date",
                 },
               ],
-              [SCHEMA.TIMESTAMP_DEFAULT, { httpQuery: "query-default-date" }],
-              [struct("ns", "date", 0, ["payloadDefaultDate"], [SCHEMA.TIMESTAMP_DEFAULT]), { httpPayload: 1 }],
+              [4 satisfies TimestampDefaultSchema, { httpQuery: "query-default-date" }],
+              [
+                struct("ns", "date", 0, ["payloadDefaultDate"], [4 satisfies TimestampDefaultSchema]),
+                { httpPayload: 1 },
+              ],
             ]
           ),
           "unit"
diff --git a/packages/core/src/submodules/protocols/json/AwsRestJsonProtocol.ts b/packages/core/src/submodules/protocols/json/AwsRestJsonProtocol.ts
index 3b1882e6247c8..1891c21c30a6b 100644
--- a/packages/core/src/submodules/protocols/json/AwsRestJsonProtocol.ts
+++ b/packages/core/src/submodules/protocols/json/AwsRestJsonProtocol.ts
@@ -3,7 +3,7 @@ import {
   HttpInterceptingShapeDeserializer,
   HttpInterceptingShapeSerializer,
 } from "@smithy/core/protocols";
-import { NormalizedSchema, SCHEMA, TypeRegistry } from "@smithy/core/schema";
+import { NormalizedSchema, TypeRegistry } from "@smithy/core/schema";
 import type {
   EndpointBearer,
   HandlerExecutionContext,
@@ -14,6 +14,7 @@ import type {
   SerdeFunctions,
   ShapeDeserializer,
   ShapeSerializer,
+  TimestampEpochSecondsSchema,
 } from "@smithy/types";
 
 import { ProtocolLib } from "../ProtocolLib";
@@ -36,7 +37,7 @@ export class AwsRestJsonProtocol extends HttpBindingProtocol {
     const settings: JsonSettings = {
       timestampFormat: {
         useTrait: true,
-        default: SCHEMA.TIMESTAMP_EPOCH_SECONDS,
+        default: 7 as const satisfies TimestampEpochSecondsSchema,
       },
       httpBindings: true,
       jsonName: true,
diff --git a/packages/core/src/submodules/protocols/json/JsonCodec.ts b/packages/core/src/submodules/protocols/json/JsonCodec.ts
index 38d085035379b..e1b6ee6dd81d6 100644
--- a/packages/core/src/submodules/protocols/json/JsonCodec.ts
+++ b/packages/core/src/submodules/protocols/json/JsonCodec.ts
@@ -1,4 +1,4 @@
-import { Codec, CodecSettings, ShapeDeserializer, ShapeSerializer } from "@smithy/types";
+import type { Codec, CodecSettings } from "@smithy/types";
 
 import { SerdeContextConfig } from "../ConfigurableSerdeContext";
 import { JsonShapeDeserializer } from "./JsonShapeDeserializer";
diff --git a/packages/core/src/submodules/protocols/json/JsonShapeDeserializer.spec.ts b/packages/core/src/submodules/protocols/json/JsonShapeDeserializer.spec.ts
index 96671d5fc1d49..231450c635882 100644
--- a/packages/core/src/submodules/protocols/json/JsonShapeDeserializer.spec.ts
+++ b/packages/core/src/submodules/protocols/json/JsonShapeDeserializer.spec.ts
@@ -1,5 +1,5 @@
-import { SCHEMA } from "@smithy/core/schema";
 import { NumericValue } from "@smithy/core/serde";
+import type { TimestampEpochSecondsSchema } from "@smithy/types";
 import { describe, expect, test as it } from "vitest";
 
 import { widget } from "../test-schema.spec";
@@ -15,7 +15,7 @@ describe(JsonShapeDeserializer.name, () => {
 
   const deserializer = new JsonShapeDeserializer({
     jsonName: true,
-    timestampFormat: { default: SCHEMA.TIMESTAMP_EPOCH_SECONDS, useTrait: true },
+    timestampFormat: { default: 7 satisfies TimestampEpochSecondsSchema, useTrait: true },
   });
 
   it("understands list sparseness", async () => {
diff --git a/packages/core/src/submodules/protocols/json/JsonShapeDeserializer.ts b/packages/core/src/submodules/protocols/json/JsonShapeDeserializer.ts
index 1040cb700ecfb..1f9ec46074ebd 100644
--- a/packages/core/src/submodules/protocols/json/JsonShapeDeserializer.ts
+++ b/packages/core/src/submodules/protocols/json/JsonShapeDeserializer.ts
@@ -1,5 +1,5 @@
 import { determineTimestampFormat } from "@smithy/core/protocols";
-import { NormalizedSchema, SCHEMA, TypeRegistry } from "@smithy/core/schema";
+import { NormalizedSchema } from "@smithy/core/schema";
 import {
   LazyJsonString,
   NumericValue,
@@ -7,7 +7,14 @@ import {
   parseRfc3339DateTimeWithOffset,
   parseRfc7231DateTime,
 } from "@smithy/core/serde";
-import { DocumentType, Schema, ShapeDeserializer } from "@smithy/types";
+import type {
+  DocumentType,
+  Schema,
+  ShapeDeserializer,
+  TimestampDateTimeSchema,
+  TimestampEpochSecondsSchema,
+  TimestampHttpDateSchema,
+} from "@smithy/types";
 import { fromBase64 } from "@smithy/util-base64";
 
 import { SerdeContextConfig } from "../ConfigurableSerdeContext";
@@ -88,11 +95,11 @@ export class JsonShapeDeserializer extends SerdeContextConfig implements ShapeDe
     if (ns.isTimestampSchema() && value != null) {
       const format = determineTimestampFormat(ns, this.settings);
       switch (format) {
-        case SCHEMA.TIMESTAMP_DATE_TIME:
+        case 5 satisfies TimestampDateTimeSchema:
           return parseRfc3339DateTimeWithOffset(value);
-        case SCHEMA.TIMESTAMP_HTTP_DATE:
+        case 6 satisfies TimestampHttpDateSchema:
           return parseRfc7231DateTime(value);
-        case SCHEMA.TIMESTAMP_EPOCH_SECONDS:
+        case 7 satisfies TimestampEpochSecondsSchema:
           return parseEpochTimestamp(value);
         default:
           console.warn("Missing timestamp format, parsing value with Date constructor:", value);
diff --git a/packages/core/src/submodules/protocols/json/JsonShapeSerializer.spec.ts b/packages/core/src/submodules/protocols/json/JsonShapeSerializer.spec.ts
index aea832e7b7238..0e64233816056 100644
--- a/packages/core/src/submodules/protocols/json/JsonShapeSerializer.spec.ts
+++ b/packages/core/src/submodules/protocols/json/JsonShapeSerializer.spec.ts
@@ -1,5 +1,5 @@
-import { SCHEMA } from "@smithy/core/schema";
 import { NumericValue } from "@smithy/core/serde";
+import type { TimestampEpochSecondsSchema } from "@smithy/types";
 import { describe, expect, test as it } from "vitest";
 
 import { widget } from "../test-schema.spec";
@@ -9,7 +9,7 @@ describe(JsonShapeSerializer.name, () => {
   it("serializes data to JSON", async () => {
     const serializer = new JsonShapeSerializer({
       jsonName: true,
-      timestampFormat: { default: SCHEMA.TIMESTAMP_EPOCH_SECONDS, useTrait: true },
+      timestampFormat: { default: 7 satisfies TimestampEpochSecondsSchema, useTrait: true },
     });
     serializer.setSerdeContext({
       base64Encoder: (input: Uint8Array) => {
diff --git a/packages/core/src/submodules/protocols/json/JsonShapeSerializer.ts b/packages/core/src/submodules/protocols/json/JsonShapeSerializer.ts
index 38c4a210099d1..9f9678a166b44 100644
--- a/packages/core/src/submodules/protocols/json/JsonShapeSerializer.ts
+++ b/packages/core/src/submodules/protocols/json/JsonShapeSerializer.ts
@@ -1,11 +1,17 @@
 import { determineTimestampFormat } from "@smithy/core/protocols";
-import { NormalizedSchema, SCHEMA } from "@smithy/core/schema";
+import { NormalizedSchema } from "@smithy/core/schema";
 import { dateToUtcString, generateIdempotencyToken, LazyJsonString, NumericValue } from "@smithy/core/serde";
-import { Schema, ShapeSerializer } from "@smithy/types";
+import type {
+  Schema,
+  ShapeSerializer,
+  TimestampDateTimeSchema,
+  TimestampEpochSecondsSchema,
+  TimestampHttpDateSchema,
+} from "@smithy/types";
 import { toBase64 } from "@smithy/util-base64";
 
 import { SerdeContextConfig } from "../ConfigurableSerdeContext";
-import { JsonSettings } from "./JsonCodec";
+import type { JsonSettings } from "./JsonCodec";
 import { JsonReplacer } from "./jsonReplacer";
 
 /**
@@ -105,11 +111,11 @@ export class JsonShapeSerializer extends SerdeContextConfig implements ShapeSeri
     if ((ns.isTimestampSchema() || ns.isDocumentSchema()) && value instanceof Date) {
       const format = determineTimestampFormat(ns, this.settings);
       switch (format) {
-        case SCHEMA.TIMESTAMP_DATE_TIME:
+        case 5 satisfies TimestampDateTimeSchema:
           return value.toISOString().replace(".000Z", "Z");
-        case SCHEMA.TIMESTAMP_HTTP_DATE:
+        case 6 satisfies TimestampHttpDateSchema:
           return dateToUtcString(value);
-        case SCHEMA.TIMESTAMP_EPOCH_SECONDS:
+        case 7 satisfies TimestampEpochSecondsSchema:
           return value.getTime() / 1000;
         default:
           console.warn("Missing timestamp format, using epoch seconds", value);
diff --git a/packages/core/src/submodules/protocols/query/AwsQueryProtocol.ts b/packages/core/src/submodules/protocols/query/AwsQueryProtocol.ts
index 970366b39aeec..4928afed995ba 100644
--- a/packages/core/src/submodules/protocols/query/AwsQueryProtocol.ts
+++ b/packages/core/src/submodules/protocols/query/AwsQueryProtocol.ts
@@ -1,7 +1,8 @@
 import { collectBody, RpcProtocol } from "@smithy/core/protocols";
-import { deref, ErrorSchema, NormalizedSchema, SCHEMA, TypeRegistry } from "@smithy/core/schema";
+import { deref, ErrorSchema, NormalizedSchema, TypeRegistry } from "@smithy/core/schema";
 import type {
   Codec,
+  DocumentSchema,
   EndpointBearer,
   HandlerExecutionContext,
   HttpRequest,
@@ -10,6 +11,7 @@ import type {
   OperationSchema,
   ResponseMetadata,
   SerdeFunctions,
+  TimestampDateTimeSchema,
 } from "@smithy/types";
 
 import { ProtocolLib } from "../ProtocolLib";
@@ -37,7 +39,7 @@ export class AwsQueryProtocol extends RpcProtocol {
     const settings = {
       timestampFormat: {
         useTrait: true,
-        default: SCHEMA.TIMESTAMP_DATE_TIME,
+        default: 5 as const satisfies TimestampDateTimeSchema,
       },
       httpBindings: false,
       xmlNamespace: options.xmlNamespace,
@@ -100,7 +102,7 @@ export class AwsQueryProtocol extends RpcProtocol {
     if (response.statusCode >= 300) {
       const bytes: Uint8Array = await collectBody(response.body, context as SerdeFunctions);
       if (bytes.byteLength > 0) {
-        Object.assign(dataObject, await deserializer.read(SCHEMA.DOCUMENT, bytes));
+        Object.assign(dataObject, await deserializer.read(15 satisfies DocumentSchema, bytes));
       }
       await this.handleError(operationSchema, context, response, dataObject, this.deserializeMetadata(response));
     }
diff --git a/packages/core/src/submodules/protocols/query/QuerySerializerSettings.ts b/packages/core/src/submodules/protocols/query/QuerySerializerSettings.ts
index 88dd858612d40..117623e1bb006 100644
--- a/packages/core/src/submodules/protocols/query/QuerySerializerSettings.ts
+++ b/packages/core/src/submodules/protocols/query/QuerySerializerSettings.ts
@@ -1,4 +1,4 @@
-import { CodecSettings } from "@smithy/types";
+import type { CodecSettings } from "@smithy/types";
 
 export type QuerySerializerSettings = CodecSettings & {
   capitalizeKeys?: boolean;
diff --git a/packages/core/src/submodules/protocols/query/QueryShapeSerializer.spec.ts b/packages/core/src/submodules/protocols/query/QueryShapeSerializer.spec.ts
index b6510be4e1056..1acb9d317e5c7 100644
--- a/packages/core/src/submodules/protocols/query/QueryShapeSerializer.spec.ts
+++ b/packages/core/src/submodules/protocols/query/QueryShapeSerializer.spec.ts
@@ -1,5 +1,5 @@
-import { SCHEMA } from "@smithy/core/schema";
 import { NumericValue } from "@smithy/core/serde";
+import type { TimestampDateTimeSchema } from "@smithy/types";
 import { describe, expect, test as it } from "vitest";
 
 import { widget } from "../test-schema.spec";
@@ -8,7 +8,7 @@ import { QueryShapeSerializer } from "./QueryShapeSerializer";
 describe(QueryShapeSerializer.name, () => {
   it("serializes data to Query", async () => {
     const serializer = new QueryShapeSerializer({
-      timestampFormat: { default: SCHEMA.TIMESTAMP_DATE_TIME, useTrait: true },
+      timestampFormat: { default: 5 satisfies TimestampDateTimeSchema, useTrait: true },
     });
     serializer.setSerdeContext({
       base64Encoder: (input: Uint8Array) => {
diff --git a/packages/core/src/submodules/protocols/query/QueryShapeSerializer.ts b/packages/core/src/submodules/protocols/query/QueryShapeSerializer.ts
index 4076bf8854636..4283471aa3241 100644
--- a/packages/core/src/submodules/protocols/query/QueryShapeSerializer.ts
+++ b/packages/core/src/submodules/protocols/query/QueryShapeSerializer.ts
@@ -1,8 +1,14 @@
 import { determineTimestampFormat, extendedEncodeURIComponent } from "@smithy/core/protocols";
-import { NormalizedSchema, SCHEMA } from "@smithy/core/schema";
+import { NormalizedSchema } from "@smithy/core/schema";
 import { generateIdempotencyToken, NumericValue } from "@smithy/core/serde";
 import { dateToUtcString } from "@smithy/smithy-client";
-import type { Schema, ShapeSerializer } from "@smithy/types";
+import type {
+  Schema,
+  ShapeSerializer,
+  TimestampDateTimeSchema,
+  TimestampEpochSecondsSchema,
+  TimestampHttpDateSchema,
+} from "@smithy/types";
 import { toBase64 } from "@smithy/util-base64";
 
 import { SerdeContextConfig } from "../ConfigurableSerdeContext";
@@ -55,13 +61,13 @@ export class QueryShapeSerializer extends SerdeContextConfig implements ShapeSer
         this.writeKey(prefix);
         const format = determineTimestampFormat(ns, this.settings);
         switch (format) {
-          case SCHEMA.TIMESTAMP_DATE_TIME:
+          case 5 satisfies TimestampDateTimeSchema:
             this.writeValue(value.toISOString().replace(".000Z", "Z"));
             break;
-          case SCHEMA.TIMESTAMP_HTTP_DATE:
+          case 6 satisfies TimestampHttpDateSchema:
             this.writeValue(dateToUtcString(value));
             break;
-          case SCHEMA.TIMESTAMP_EPOCH_SECONDS:
+          case 7 satisfies TimestampEpochSecondsSchema:
             this.writeValue(String(value.getTime() / 1000));
             break;
         }
diff --git a/packages/core/src/submodules/protocols/schema-testing/schema-documents.spec.ts b/packages/core/src/submodules/protocols/schema-testing/schema-documents.spec.ts
index 28a25291375a4..d30349152fb44 100644
--- a/packages/core/src/submodules/protocols/schema-testing/schema-documents.spec.ts
+++ b/packages/core/src/submodules/protocols/schema-testing/schema-documents.spec.ts
@@ -1,5 +1,18 @@
-import { list, map, NormalizedSchema, SCHEMA, sim, struct, TypeRegistry } from "@smithy/core/schema";
-import { DocumentType, Schema } from "@smithy/types";
+import { list, map, NormalizedSchema, sim, struct, TypeRegistry } from "@smithy/core/schema";
+import type {
+  BigDecimalSchema,
+  BigIntegerSchema,
+  BlobSchema,
+  BooleanSchema,
+  DocumentSchema,
+  DocumentType,
+  NumericSchema,
+  StringSchema,
+  TimestampDateTimeSchema,
+  TimestampDefaultSchema,
+  TimestampEpochSecondsSchema,
+  TimestampHttpDateSchema,
+} from "@smithy/types";
 import { describe, expect, test as it } from "vitest";
 
 import { JsonCodec, JsonSettings } from "../json/JsonCodec";
@@ -35,27 +48,27 @@ export var OmniWidget = struct(
     "structure",
   ],
   [
-    SCHEMA.BLOB,
-    SCHEMA.BOOLEAN,
+    21 satisfies BlobSchema,
+    2 satisfies BooleanSchema,
     sim("smithy.api", "String", 0, {
       jsonName: "String",
       xmlName: "String",
     }),
-    sim("smithy.api", "Byte", SCHEMA.NUMERIC, 0),
-    sim("smithy.api", "Short", SCHEMA.NUMERIC, 0),
-    sim("smithy.api", "Integer", SCHEMA.NUMERIC, 0),
-    sim("smithy.api", "Long", SCHEMA.NUMERIC, 0),
-    sim("smithy.api", "Float", SCHEMA.NUMERIC, 0),
-    SCHEMA.NUMERIC, // double
-    SCHEMA.BIG_INTEGER,
-    SCHEMA.BIG_DECIMAL,
-    SCHEMA.TIMESTAMP_DEFAULT,
-    SCHEMA.TIMESTAMP_DATE_TIME,
-    SCHEMA.TIMESTAMP_HTTP_DATE,
-    SCHEMA.TIMESTAMP_EPOCH_SECONDS,
-    SCHEMA.DOCUMENT,
-    sim("smithy.api", "Enum", SCHEMA.STRING, 0),
-    sim("smithy.api", "IntEnum", SCHEMA.NUMERIC, 0),
+    sim("smithy.api", "Byte", 1 satisfies NumericSchema, 0),
+    sim("smithy.api", "Short", 1 satisfies NumericSchema, 0),
+    sim("smithy.api", "Integer", 1 satisfies NumericSchema, 0),
+    sim("smithy.api", "Long", 1 satisfies NumericSchema, 0),
+    sim("smithy.api", "Float", 1 satisfies NumericSchema, 0),
+    1 satisfies NumericSchema, // double
+    17 satisfies BigIntegerSchema,
+    19 satisfies BigDecimalSchema,
+    4 satisfies TimestampDefaultSchema,
+    5 satisfies TimestampDateTimeSchema,
+    6 satisfies TimestampHttpDateSchema,
+    7 satisfies TimestampEpochSecondsSchema,
+    15 satisfies DocumentSchema,
+    sim("smithy.api", "Enum", 0 satisfies StringSchema, 0),
+    sim("smithy.api", "IntEnum", 1 satisfies NumericSchema, 0),
     list("smithy.example", "OmniWidgetList", 0, () => OmniWidget),
     map("smithy.example", "OmniWidgetMap", 0, 0, () => OmniWidget),
     () => OmniWidget,
@@ -66,10 +79,11 @@ function getJsonCodec(test: { settings: JsonSettings }): JsonCodec {
   const { settings } = test;
   const format =
     {
-      "date-time": SCHEMA.TIMESTAMP_DATE_TIME,
-      "http-date": SCHEMA.TIMESTAMP_HTTP_DATE,
-      "epoch-seconds": SCHEMA.TIMESTAMP_EPOCH_SECONDS,
-    }[(settings.timestampFormat?.default as unknown as string) ?? "epoch-seconds"] ?? SCHEMA.TIMESTAMP_EPOCH_SECONDS;
+      "date-time": 5 as const satisfies TimestampDateTimeSchema,
+      "http-date": 6 as const satisfies TimestampHttpDateSchema,
+      "epoch-seconds": 7 as const satisfies TimestampEpochSecondsSchema,
+    }[(settings.timestampFormat?.default as unknown as string) ?? "epoch-seconds"] ??
+    (7 as const satisfies TimestampEpochSecondsSchema);
   return new JsonCodec({
     jsonName: settings.jsonName ?? false,
     timestampFormat: {
@@ -93,7 +107,7 @@ function readDocument(deserializer: JsonShapeDeserializer, data: DocumentType):
     const ns = NormalizedSchema.of(schema);
     return deserializer.readObject(ns, object);
   }
-  return deserializer.readObject(SCHEMA.DOCUMENT, data);
+  return deserializer.readObject(15 satisfies DocumentSchema, data);
 }
 
 describe("schema conversion tests for serializations, data objects, and documents", () => {
@@ -105,13 +119,13 @@ describe("schema conversion tests for serializations, data objects, and document
       const serializer = codec.createSerializer();
       const deserializer = codec.createDeserializer();
 
-      serializer.write(SCHEMA.DOCUMENT, test.serialized);
+      serializer.write(15 satisfies DocumentSchema, test.serialized);
       const serialization = serializer.flush();
-      const documentFromSerialization = await deserializer.read(SCHEMA.DOCUMENT, serialization);
+      const documentFromSerialization = await deserializer.read(15 satisfies DocumentSchema, serialization);
       const canonicalDataObject = await deserializer.read(subjectSchema, serialization);
 
       serializer.writeDiscriminatedDocument(subjectSchema, canonicalDataObject);
-      const documentFromDataObject = await deserializer.read(SCHEMA.DOCUMENT, serializer.flush());
+      const documentFromDataObject = await deserializer.read(15 satisfies DocumentSchema, serializer.flush());
 
       // 1. data object from serialization
       expect(typeof documentFromSerialization).toBe("object");
@@ -130,13 +144,13 @@ describe("schema conversion tests for serializations, data objects, and document
       expect(serializationFromDataObject).toEqual(serialization);
 
       // 5. serialization from serialization document
-      serializer.write(SCHEMA.DOCUMENT, documentFromSerialization);
+      serializer.write(15 satisfies DocumentSchema, documentFromSerialization);
       const serializationFromSerializedDocument = serializer.flush();
       expect(serializationFromSerializedDocument).toEqual(serialization);
 
       // 6. serialization from data object document
       delete documentFromDataObject.__type;
-      serializer.write(SCHEMA.DOCUMENT, documentFromDataObject);
+      serializer.write(15 satisfies DocumentSchema, documentFromDataObject);
       const serializationFromDocumentFromDataObject = serializer.flush();
       expect(serializationFromDocumentFromDataObject).toEqual(serialization);
     });
diff --git a/packages/core/src/submodules/protocols/test-schema.spec.ts b/packages/core/src/submodules/protocols/test-schema.spec.ts
index 85c00d6456416..ee5a7185b2288 100644
--- a/packages/core/src/submodules/protocols/test-schema.spec.ts
+++ b/packages/core/src/submodules/protocols/test-schema.spec.ts
@@ -1,4 +1,11 @@
-import { list, map, op, SCHEMA, sim, struct } from "@smithy/core/schema";
+import { list, map, op, sim, struct } from "@smithy/core/schema";
+import type {
+  BigDecimalSchema,
+  BigIntegerSchema,
+  BlobSchema,
+  NumericSchema,
+  TimestampEpochSecondsSchema,
+} from "@smithy/types";
 import { describe, test as it } from "vitest";
 
 describe("testing schema export", () => {
@@ -15,12 +22,12 @@ export const widget = struct(
     [list("", "List", 0, 0), { sparse: 1 }],
     map("", "Map", 0, 0, 0),
     [map("", "Map", 0, 0, 0), { sparse: 1 }],
-    SCHEMA.BLOB,
+    21 satisfies BlobSchema,
     sim("", "Media", 0, { mediaType: "application/json" }),
-    SCHEMA.TIMESTAMP_EPOCH_SECONDS,
-    SCHEMA.BIG_INTEGER,
-    SCHEMA.BIG_DECIMAL,
-    SCHEMA.NUMERIC,
+    7 satisfies TimestampEpochSecondsSchema,
+    17 satisfies BigIntegerSchema,
+    19 satisfies BigDecimalSchema,
+    1 satisfies NumericSchema,
   ]
 );
 
diff --git a/packages/core/src/submodules/protocols/xml/AwsRestXmlProtocol.ts b/packages/core/src/submodules/protocols/xml/AwsRestXmlProtocol.ts
index c9a9f8a7988b0..48a43e1357e94 100644
--- a/packages/core/src/submodules/protocols/xml/AwsRestXmlProtocol.ts
+++ b/packages/core/src/submodules/protocols/xml/AwsRestXmlProtocol.ts
@@ -3,7 +3,7 @@ import {
   HttpInterceptingShapeDeserializer,
   HttpInterceptingShapeSerializer,
 } from "@smithy/core/protocols";
-import { NormalizedSchema, OperationSchema, SCHEMA, TypeRegistry } from "@smithy/core/schema";
+import { NormalizedSchema, OperationSchema, TypeRegistry } from "@smithy/core/schema";
 import type {
   EndpointBearer,
   HandlerExecutionContext,
@@ -14,6 +14,7 @@ import type {
   SerdeFunctions,
   ShapeDeserializer,
   ShapeSerializer,
+  TimestampDateTimeSchema,
 } from "@smithy/types";
 
 import { ProtocolLib } from "../ProtocolLib";
@@ -34,7 +35,7 @@ export class AwsRestXmlProtocol extends HttpBindingProtocol {
     const settings: XmlSettings = {
       timestampFormat: {
         useTrait: true,
-        default: SCHEMA.TIMESTAMP_DATE_TIME,
+        default: 5 as const satisfies TimestampDateTimeSchema,
       },
       httpBindings: true,
       xmlNamespace: options.xmlNamespace,
diff --git a/packages/core/src/submodules/protocols/xml/XmlCodec.ts b/packages/core/src/submodules/protocols/xml/XmlCodec.ts
index c1271b6907f20..cc418b80755a6 100644
--- a/packages/core/src/submodules/protocols/xml/XmlCodec.ts
+++ b/packages/core/src/submodules/protocols/xml/XmlCodec.ts
@@ -1,4 +1,4 @@
-import { Codec, CodecSettings, ShapeDeserializer, ShapeSerializer } from "@smithy/types";
+import type { Codec, CodecSettings } from "@smithy/types";
 
 import { SerdeContextConfig } from "../ConfigurableSerdeContext";
 import { XmlShapeDeserializer } from "./XmlShapeDeserializer";
diff --git a/packages/core/src/submodules/protocols/xml/XmlShapeDeserializer.spec.ts b/packages/core/src/submodules/protocols/xml/XmlShapeDeserializer.spec.ts
index 344a7266886c3..7bdfd27f0ec4b 100644
--- a/packages/core/src/submodules/protocols/xml/XmlShapeDeserializer.spec.ts
+++ b/packages/core/src/submodules/protocols/xml/XmlShapeDeserializer.spec.ts
@@ -1,5 +1,5 @@
-import { SCHEMA } from "@smithy/core/schema";
 import { NumericValue } from "@smithy/core/serde";
+import type { TimestampDateTimeSchema } from "@smithy/types";
 import { describe, expect, test as it } from "vitest";
 
 import { widget } from "../test-schema.spec";
@@ -16,7 +16,7 @@ describe("", () => {
     const deserializer = new XmlShapeDeserializer({
       httpBindings: true,
       serviceNamespace: "namespace",
-      timestampFormat: { default: SCHEMA.TIMESTAMP_DATE_TIME, useTrait: true },
+      timestampFormat: { default: 5 satisfies TimestampDateTimeSchema, useTrait: true },
       xmlNamespace: "namespace",
     });
 
diff --git a/packages/core/src/submodules/protocols/xml/XmlShapeSerializer.spec.ts b/packages/core/src/submodules/protocols/xml/XmlShapeSerializer.spec.ts
index 013fdb37ee5dd..90e3280d7e4be 100644
--- a/packages/core/src/submodules/protocols/xml/XmlShapeSerializer.spec.ts
+++ b/packages/core/src/submodules/protocols/xml/XmlShapeSerializer.spec.ts
@@ -1,5 +1,5 @@
-import { SCHEMA } from "@smithy/core/schema";
 import { NumericValue } from "@smithy/core/serde";
+import type { TimestampDateTimeSchema } from "@smithy/types";
 import { describe, expect, test as it } from "vitest";
 
 import { widget } from "../test-schema.spec";
@@ -11,7 +11,7 @@ describe(XmlShapeSerializer.name, () => {
     const serializer = new XmlShapeSerializer({
       xmlNamespace: "namespace",
       serviceNamespace: "namespace",
-      timestampFormat: { default: SCHEMA.TIMESTAMP_DATE_TIME, useTrait: true },
+      timestampFormat: { default: 5 satisfies TimestampDateTimeSchema, useTrait: true },
     });
     serializer.setSerdeContext({
       base64Encoder: (input: Uint8Array) => {
diff --git a/packages/core/src/submodules/protocols/xml/XmlShapeSerializer.ts b/packages/core/src/submodules/protocols/xml/XmlShapeSerializer.ts
index b4d370e292f7b..2ddc329f43ed8 100644
--- a/packages/core/src/submodules/protocols/xml/XmlShapeSerializer.ts
+++ b/packages/core/src/submodules/protocols/xml/XmlShapeSerializer.ts
@@ -1,9 +1,15 @@
 import { XmlNode, XmlText } from "@aws-sdk/xml-builder";
 import { determineTimestampFormat } from "@smithy/core/protocols";
-import { NormalizedSchema, SCHEMA } from "@smithy/core/schema";
+import { NormalizedSchema } from "@smithy/core/schema";
 import { generateIdempotencyToken, NumericValue } from "@smithy/core/serde";
 import { dateToUtcString } from "@smithy/smithy-client";
-import type { Schema as ISchema, ShapeSerializer } from "@smithy/types";
+import type {
+  Schema as ISchema,
+  ShapeSerializer,
+  TimestampDateTimeSchema,
+  TimestampEpochSecondsSchema,
+  TimestampHttpDateSchema,
+} from "@smithy/types";
 import { fromBase64, toBase64 } from "@smithy/util-base64";
 
 import { SerdeContextConfig } from "../ConfigurableSerdeContext";
@@ -262,13 +268,13 @@ export class XmlShapeSerializer extends SerdeContextConfig implements ShapeSeria
       } else if (ns.isTimestampSchema() && value instanceof Date) {
         const format = determineTimestampFormat(ns, this.settings);
         switch (format) {
-          case SCHEMA.TIMESTAMP_DATE_TIME:
+          case 5 satisfies TimestampDateTimeSchema:
             nodeContents = value.toISOString().replace(".000Z", "Z");
             break;
-          case SCHEMA.TIMESTAMP_HTTP_DATE:
+          case 6 satisfies TimestampHttpDateSchema:
             nodeContents = dateToUtcString(value);
             break;
-          case SCHEMA.TIMESTAMP_EPOCH_SECONDS:
+          case 7 satisfies TimestampEpochSecondsSchema:
             nodeContents = String(value.getTime() / 1000);
             break;
           default: