diff --git a/.chronus/changes/python-fix-azure-spec-detection-2026-3-29-12-59-39.md b/.chronus/changes/python-fix-azure-spec-detection-2026-3-29-12-59-39.md
new file mode 100644
index 00000000000..0afd9ff9e7f
--- /dev/null
+++ b/.chronus/changes/python-fix-azure-spec-detection-2026-3-29-12-59-39.md
@@ -0,0 +1,7 @@
+---
+changeKind: internal
+packages:
+  - "@typespec/http-client-python"
+---
+
+Consolidate regenerate-common.ts into regenerate.ts and fix azure spec detection using azure-http-specs path check
\ No newline at end of file
diff --git a/packages/http-client-python/eng/scripts/ci/regenerate-common.ts b/packages/http-client-python/eng/scripts/ci/regenerate-common.ts
deleted file mode 100644
index 8dd426152b4..00000000000
--- a/packages/http-client-python/eng/scripts/ci/regenerate-common.ts
+++ /dev/null
@@ -1,496 +0,0 @@
-import { promises } from "fs";
-import { dirname, join, relative, resolve } from "path";
-
-// ---- Shared constants ----
-
-export const SKIP_SPECS: string[] = ["type/file", "service/multiple-services"];
-
-export const SpecialFlags: Record<string, Record<string, any>> = {
-  azure: {
-    "generate-test": true,
-    "generate-sample": true,
-  },
-};
-
-// ---- Base emitter options (shared across repos) ----
-
-export const BASE_AZURE_EMITTER_OPTIONS: Record<
-  string,
-  Record<string, string> | Record<string, string>[]
-> = {
-  "azure/client-generator-core/access": {
-    namespace: "specs.azure.clientgenerator.core.access",
-  },
-  "azure/client-generator-core/alternate-type": {
-    namespace: "specs.azure.clientgenerator.core.alternatetype",
-  },
-  "azure/client-generator-core/api-version": {
-    namespace: "specs.azure.clientgenerator.core.apiversion",
-  },
-  "azure/client-generator-core/client-initialization/default": {
-    namespace: "specs.azure.clientgenerator.core.clientinitialization.default",
-  },
-  "azure/client-generator-core/client-initialization/individually": {
-    namespace: "specs.azure.clientgenerator.core.clientinitialization.individually",
-  },
-  "azure/client-generator-core/client-initialization/individuallyParent": {
-    namespace: "specs.azure.clientgenerator.core.clientinitialization.individuallyparent",
-  },
-  "azure/client-generator-core/client-location": {
-    namespace: "specs.azure.clientgenerator.core.clientlocation",
-  },
-  "azure/client-generator-core/deserialize-empty-string-as-null": {
-    namespace: "specs.azure.clientgenerator.core.emptystring",
-  },
-  "azure/client-generator-core/flatten-property": {
-    namespace: "specs.azure.clientgenerator.core.flattenproperty",
-  },
-  "azure/client-generator-core/usage": {
-    namespace: "specs.azure.clientgenerator.core.usage",
-  },
-  "azure/client-generator-core/client-doc": {
-    namespace: "specs.azure.clientgenerator.core.clientdoc",
-  },
-  "azure/client-generator-core/override": {
-    namespace: "specs.azure.clientgenerator.core.override",
-  },
-  "azure/client-generator-core/hierarchy-building": {
-    namespace: "specs.azure.clientgenerator.core.hierarchybuilding",
-  },
-  "azure/core/basic": {
-    namespace: "specs.azure.core.basic",
-  },
-  "azure/core/lro/rpc": {
-    namespace: "specs.azure.core.lro.rpc",
-  },
-  "azure/core/lro/standard": {
-    namespace: "specs.azure.core.lro.standard",
-  },
-  "azure/core/model": {
-    namespace: "specs.azure.core.model",
-  },
-  "azure/core/page": {
-    namespace: "specs.azure.core.page",
-  },
-  "azure/core/scalar": {
-    namespace: "specs.azure.core.scalar",
-  },
-  "azure/core/traits": {
-    namespace: "specs.azure.core.traits",
-  },
-  "azure/encode/duration": {
-    namespace: "specs.azure.encode.duration",
-  },
-  "azure/example/basic": {
-    namespace: "specs.azure.example.basic",
-  },
-  "azure/payload/pageable": {
-    namespace: "specs.azure.payload.pageable",
-  },
-  "azure/versioning/previewVersion": {
-    namespace: "specs.azure.versioning.previewversion",
-  },
-  "client/structure/default": {
-    namespace: "client.structure.service",
-  },
-  "client/structure/multi-client": {
-    "package-name": "client-structure-multiclient",
-    namespace: "client.structure.multiclient",
-  },
-  "client/structure/renamed-operation": {
-    "package-name": "client-structure-renamedoperation",
-    namespace: "client.structure.renamedoperation",
-  },
-  "client/structure/two-operation-group": {
-    "package-name": "client-structure-twooperationgroup",
-    namespace: "client.structure.twooperationgroup",
-  },
-  "client/naming": {
-    namespace: "client.naming.main",
-  },
-  "client/overload": {
-    namespace: "client.overload",
-  },
-  "encode/duration": {
-    namespace: "encode.duration",
-  },
-  "encode/numeric": {
-    namespace: "encode.numeric",
-  },
-  "parameters/basic": {
-    namespace: "parameters.basic",
-  },
-  "parameters/spread": {
-    namespace: "parameters.spread",
-  },
-  "payload/content-negotiation": {
-    namespace: "payload.contentnegotiation",
-  },
-  "payload/multipart": {
-    namespace: "payload.multipart",
-  },
-  "serialization/encoded-name/json": {
-    namespace: "serialization.encodedname.json",
-  },
-  "special-words": {
-    namespace: "specialwords",
-  },
-  "service/multi-service": {
-    namespace: "service.multiservice",
-  },
-};
-
-export const BASE_EMITTER_OPTIONS: Record<
-  string,
-  Record<string, string> | Record<string, string>[]
-> = {
-  "resiliency/srv-driven/old.tsp": {
-    "package-name": "resiliency-srv-driven1",
-    namespace: "resiliency.srv.driven1",
-    "package-mode": "azure-dataplane",
-    "package-pprint-name": "ResiliencySrvDriven1",
-  },
-  "resiliency/srv-driven": {
-    "package-name": "resiliency-srv-driven2",
-    namespace: "resiliency.srv.driven2",
-    "package-mode": "azure-dataplane",
-    "package-pprint-name": "ResiliencySrvDriven2",
-  },
-  "authentication/api-key": {
-    "clear-output-folder": "true",
-  },
-  "authentication/http/custom": {
-    "package-name": "authentication-http-custom",
-    namespace: "authentication.http.custom",
-    "package-pprint-name": "Authentication Http Custom",
-  },
-  "authentication/union": [
-    {
-      "package-name": "authentication-union",
-      namespace: "authentication.union",
-    },
-    {
-      "package-name": "setuppy-authentication-union",
-      namespace: "setuppy.authentication.union",
-      "keep-setup-py": "true",
-    },
-  ],
-  "type/array": {
-    "package-name": "typetest-array",
-    namespace: "typetest.array",
-  },
-  "type/dictionary": {
-    "package-name": "typetest-dictionary",
-    namespace: "typetest.dictionary",
-  },
-  "type/enum/extensible": {
-    "package-name": "typetest-enum-extensible",
-    namespace: "typetest.enum.extensible",
-  },
-  "type/enum/fixed": {
-    "package-name": "typetest-enum-fixed",
-    namespace: "typetest.enum.fixed",
-  },
-  "type/model/empty": {
-    "package-name": "typetest-model-empty",
-    namespace: "typetest.model.empty",
-  },
-  "type/model/inheritance/enum-discriminator": {
-    "package-name": "typetest-model-enumdiscriminator",
-    namespace: "typetest.model.enumdiscriminator",
-  },
-  "type/model/inheritance/nested-discriminator": {
-    "package-name": "typetest-model-nesteddiscriminator",
-    namespace: "typetest.model.nesteddiscriminator",
-  },
-  "type/model/inheritance/not-discriminated": {
-    "package-name": "typetest-model-notdiscriminated",
-    namespace: "typetest.model.notdiscriminated",
-  },
-  "type/model/inheritance/single-discriminator": {
-    "package-name": "typetest-model-singlediscriminator",
-    namespace: "typetest.model.singlediscriminator",
-  },
-  "type/model/inheritance/recursive": [
-    {
-      "package-name": "typetest-model-recursive",
-      namespace: "typetest.model.recursive",
-    },
-    {
-      // basic test for configuration "generation-subdir"
-      "package-name": "generation-subdir",
-      namespace: "generation.subdir",
-      "generation-subdir": "_generated",
-      "generate-test": "false",
-      "clear-output-folder": "true",
-    },
-  ],
-  "type/model/usage": {
-    "package-name": "typetest-model-usage",
-    namespace: "typetest.model.usage",
-  },
-  "type/model/visibility": [
-    {
-      "package-name": "typetest-model-visibility",
-      namespace: "typetest.model.visibility",
-    },
-    {
-      "package-name": "headasbooleantrue",
-      namespace: "headasbooleantrue",
-      "head-as-boolean": "true",
-    },
-    {
-      "package-name": "headasbooleanfalse",
-      namespace: "headasbooleanfalse",
-      "head-as-boolean": "false",
-    },
-  ],
-  "type/property/nullable": {
-    "package-name": "typetest-property-nullable",
-    namespace: "typetest.property.nullable",
-  },
-  "type/property/optionality": {
-    "package-name": "typetest-property-optional",
-    namespace: "typetest.property.optional",
-  },
-  "type/property/additional-properties": {
-    "package-name": "typetest-property-additionalproperties",
-    namespace: "typetest.property.additionalproperties",
-  },
-  "type/scalar": {
-    "package-name": "typetest-scalar",
-    namespace: "typetest.scalar",
-  },
-  "type/property/value-types": {
-    "package-name": "typetest-property-valuetypes",
-    namespace: "typetest.property.valuetypes",
-  },
-  "type/union": {
-    "package-name": "typetest-union",
-    namespace: "typetest.union",
-  },
-  "type/union/discriminated": {
-    "package-name": "typetest-discriminatedunion",
-    namespace: "typetest.discriminatedunion",
-  },
-  "type/file": {
-    "package-name": "typetest-file",
-    namespace: "typetest.file",
-  },
-  documentation: {
-    "package-name": "specs-documentation",
-    namespace: "specs.documentation",
-  },
-  "versioning/added": [
-    {
-      "package-name": "versioning-added",
-      namespace: "versioning.added",
-    },
-    // check whether import of _validation.py/_types.py works when "generation-subdir" is configured
-    {
-      "package-name": "generation-subdir2",
-      namespace: "generation.subdir2",
-      "generate-test": "false",
-      "generation-subdir": "_generated",
-    },
-  ],
-};
-
-// ---- Shared interfaces ----
-
-export interface TspCommand {
-  outputDir: string;
-  command: string | string[];
-}
-
-export interface RegenerateFlagsInput {
-  flavor?: string;
-  debug?: boolean;
-  name?: string;
-  pyodide?: boolean;
-  jobs?: number;
-}
-
-export interface RegenerateFlags {
-  flavor: string;
-  debug: boolean;
-  name?: string;
-  pyodide?: boolean;
-}
-
-export interface RegenerateConfig {
-  azureHttpSpecs: string;
-  httpSpecs: string;
-  emitterOptions: Record<string, Record<string, string> | Record<string, string>[]>;
-  azureEmitterOptions: Record<string, Record<string, string> | Record<string, string>[]>;
-  preprocess: (flags: RegenerateFlagsInput) => Promise<void>;
-  getCmdList: (spec: string, flags: RegenerateFlags) => TspCommand[];
-  executeCommand: (cmd: TspCommand) => Promise<void>;
-}
-
-// ---- Shared utility functions ----
-
-export function toPosix(dir: string): string {
-  return dir.replace(/\\/g, "/");
-}
-
-export function getEmitterOption(
-  spec: string,
-  flavor: string,
-  config: RegenerateConfig,
-): Record<string, string>[] {
-  const specDir = spec.includes("azure") ? config.azureHttpSpecs : config.httpSpecs;
-  const relativeSpec = toPosix(relative(specDir, spec));
-  const key = relativeSpec.includes("resiliency/srv-driven/old.tsp")
-    ? relativeSpec
-    : dirname(relativeSpec);
-  const emitter_options = config.emitterOptions[key] ||
-    (flavor === "azure" ? config.azureEmitterOptions[key] : [{}]) || [{}];
-  return Array.isArray(emitter_options) ? emitter_options : [emitter_options];
-}
-
-export async function getSubdirectories(
-  baseDir: string,
-  flags: RegenerateFlags,
-): Promise<string[]> {
-  const subdirectories: string[] = [];
-
-  async function searchDir(currentDir: string) {
-    const items = await promises.readdir(currentDir, { withFileTypes: true });
-
-    const promisesArray = items.map(async (item) => {
-      const subDirPath = join(currentDir, item.name);
-      if (item.isDirectory()) {
-        const mainTspPath = join(subDirPath, "main.tsp");
-        const clientTspPath = join(subDirPath, "client.tsp");
-
-        const mainTspRelativePath = toPosix(relative(baseDir, mainTspPath));
-
-        if (SKIP_SPECS.some((skipSpec) => mainTspRelativePath.includes(skipSpec))) return;
-
-        const hasMainTsp = await promises
-          .access(mainTspPath)
-          .then(() => true)
-          .catch(() => false);
-        const hasClientTsp = await promises
-          .access(clientTspPath)
-          .then(() => true)
-          .catch(() => false);
-
-        if (mainTspRelativePath.toLowerCase().includes(flags.name || "")) {
-          if (mainTspRelativePath.includes("resiliency/srv-driven")) {
-            subdirectories.push(resolve(subDirPath, "old.tsp"));
-          }
-          if (hasClientTsp) {
-            subdirectories.push(resolve(subDirPath, "client.tsp"));
-          } else if (hasMainTsp) {
-            subdirectories.push(resolve(subDirPath, "main.tsp"));
-          }
-        }
-
-        // Recursively search in the subdirectory
-        await searchDir(subDirPath);
-      }
-    });
-
-    await Promise.all(promisesArray);
-  }
-
-  await searchDir(baseDir);
-  return subdirectories;
-}
-
-export async function runTaskPool(
-  tasks: Array<() => Promise<void>>,
-  poolLimit: number,
-): Promise<void> {
-  const executing: Set<Promise<void>> = new Set();
-
-  for (const task of tasks) {
-    // Start the task and remove from set when done
-    const p: Promise<void> = task().finally(() => executing.delete(p));
-    executing.add(p);
-
-    // If at capacity, wait for one to complete
-    if (executing.size >= poolLimit) {
-      await Promise.race(executing);
-    }
-  }
-
-  // Wait for remaining tasks
-  await Promise.all(executing);
-}
-
-export async function regenerate(
-  flags: RegenerateFlagsInput,
-  config: RegenerateConfig,
-): Promise<void> {
-  if (flags.flavor === undefined) {
-    await regenerate({ flavor: "azure", ...flags }, config);
-    await regenerate({ flavor: "unbranded", ...flags }, config);
-  } else {
-    await config.preprocess(flags);
-
-    const flagsResolved: RegenerateFlags = { debug: false, flavor: flags.flavor, ...flags };
-    const subdirectoriesForAzure = await getSubdirectories(config.azureHttpSpecs, flagsResolved);
-    const subdirectoriesForNonAzure = await getSubdirectories(config.httpSpecs, flagsResolved);
-    const subdirectories =
-      flags.flavor === "azure"
-        ? [...subdirectoriesForAzure, ...subdirectoriesForNonAzure]
-        : subdirectoriesForNonAzure;
-    const cmdList: TspCommand[] = subdirectories.flatMap((subdirectory) =>
-      config.getCmdList(subdirectory, flagsResolved),
-    );
-
-    // Create tasks as functions for the pool
-    const tasks: Array<() => Promise<void>> = cmdList.map((tspCommand) => {
-      return () => config.executeCommand(tspCommand);
-    });
-
-    // Run tasks with a concurrency limit
-    // Default: 30 jobs, or use provided value
-    const poolLimit = flags.jobs ?? 30;
-    await runTaskPool(tasks, poolLimit);
-  }
-}
-
-// Preprocess: create files that should be deleted after regeneration (for testing)
-export async function preprocess(flavor: string, generatedFolder: string): Promise<void> {
-  if (flavor === "azure") {
-    // Use tests/generated/<flavor>/<package> structure (same as output)
-    const testsGeneratedDir = resolve(generatedFolder, "../tests/generated/azure");
-
-    const DELETE_CONTENT = "# This file is to be deleted after regeneration";
-    const DELETE_FILE = "to_be_deleted.py";
-    const entries: { folder: string[]; file: string; content: string }[] = [
-      {
-        folder: ["authentication-api-key", "authentication", "apikey", "_operations"],
-        file: DELETE_FILE,
-        content: DELETE_CONTENT,
-      },
-      {
-        folder: ["generation-subdir", "generation", "subdir", "_generated"],
-        file: DELETE_FILE,
-        content: DELETE_CONTENT,
-      },
-      {
-        folder: ["generation-subdir", "generated_tests"],
-        file: DELETE_FILE,
-        content: DELETE_CONTENT,
-      },
-      {
-        folder: ["generation-subdir", "generation", "subdir"],
-        file: "to_be_kept.py",
-        content: "# This file is to be kept after regeneration",
-      },
-    ];
-
-    await Promise.all(
-      entries.map(async ({ folder, file, content }) => {
-        const targetFolder = join(testsGeneratedDir, ...folder);
-        await promises.mkdir(targetFolder, { recursive: true });
-        await promises.writeFile(join(targetFolder, file), content);
-      }),
-    );
-  }
-}
diff --git a/packages/http-client-python/eng/scripts/ci/regenerate.ts b/packages/http-client-python/eng/scripts/ci/regenerate.ts
index 958c871849e..a65230db578 100644
--- a/packages/http-client-python/eng/scripts/ci/regenerate.ts
+++ b/packages/http-client-python/eng/scripts/ci/regenerate.ts
@@ -8,21 +8,13 @@
 
 import { compile, NodeHost } from "@typespec/compiler";
 import { execSync } from "child_process";
-import { existsSync, readdirSync, rmSync } from "fs";
+import { existsSync, rmSync } from "fs";
+import { access, mkdir, readdir, writeFile } from "fs/promises";
 import { platform } from "os";
 import { dirname, join, relative, resolve } from "path";
 import pc from "picocolors";
 import { fileURLToPath } from "url";
 import { parseArgs } from "util";
-import {
-  BASE_AZURE_EMITTER_OPTIONS,
-  BASE_EMITTER_OPTIONS,
-  getSubdirectories,
-  preprocess,
-  SpecialFlags,
-  toPosix,
-  type RegenerateFlags,
-} from "./regenerate-common.js";
 
 // Parse arguments
 const argv = parseArgs({
@@ -83,21 +75,151 @@ ${pc.bold("Examples:")}
   process.exit(0);
 }
 
-// Get paths
-const SCRIPT_DIR = dirname(fileURLToPath(import.meta.url));
-const PLUGIN_DIR = argv.values.pluginDir
-  ? resolve(argv.values.pluginDir)
-  : resolve(SCRIPT_DIR, "../../../");
-const AZURE_HTTP_SPECS = resolve(PLUGIN_DIR, "node_modules/@azure-tools/azure-http-specs/specs");
-const HTTP_SPECS = resolve(PLUGIN_DIR, "node_modules/@typespec/http-specs/specs");
-const GENERATED_FOLDER = argv.values.generatedFolder
-  ? resolve(argv.values.generatedFolder)
-  : resolve(PLUGIN_DIR, "generator");
-const EMITTER_NAME = argv.values.emitterName || "@typespec/http-client-python";
+// ---- Shared constants ----
+
+const SKIP_SPECS: string[] = ["type/file", "service/multiple-services"];
+
+const SpecialFlags: Record<string, Record<string, any>> = {
+  azure: {
+    "generate-test": true,
+    "generate-sample": true,
+  },
+};
+
+function toPosix(dir: string): string {
+  return dir.replace(/\\/g, "/");
+}
+
+interface RegenerateFlags {
+  flavor: string;
+  debug: boolean;
+  name?: string;
+  pyodide?: boolean;
+}
+
+// ---- Base emitter options ----
 
-// Emitter options
 const AZURE_EMITTER_OPTIONS: Record<string, Record<string, string> | Record<string, string>[]> = {
-  ...BASE_AZURE_EMITTER_OPTIONS,
+  "azure/client-generator-core/access": {
+    namespace: "specs.azure.clientgenerator.core.access",
+  },
+  "azure/client-generator-core/alternate-type": {
+    namespace: "specs.azure.clientgenerator.core.alternatetype",
+  },
+  "azure/client-generator-core/api-version": {
+    namespace: "specs.azure.clientgenerator.core.apiversion",
+  },
+  "azure/client-generator-core/client-initialization/default": {
+    namespace: "specs.azure.clientgenerator.core.clientinitialization.default",
+  },
+  "azure/client-generator-core/client-initialization/individually": {
+    namespace: "specs.azure.clientgenerator.core.clientinitialization.individually",
+  },
+  "azure/client-generator-core/client-initialization/individuallyParent": {
+    namespace: "specs.azure.clientgenerator.core.clientinitialization.individuallyparent",
+  },
+  "azure/client-generator-core/client-location": {
+    namespace: "specs.azure.clientgenerator.core.clientlocation",
+  },
+  "azure/client-generator-core/deserialize-empty-string-as-null": {
+    namespace: "specs.azure.clientgenerator.core.emptystring",
+  },
+  "azure/client-generator-core/flatten-property": {
+    namespace: "specs.azure.clientgenerator.core.flattenproperty",
+  },
+  "azure/client-generator-core/usage": {
+    namespace: "specs.azure.clientgenerator.core.usage",
+  },
+  "azure/client-generator-core/client-doc": {
+    namespace: "specs.azure.clientgenerator.core.clientdoc",
+  },
+  "azure/client-generator-core/override": {
+    namespace: "specs.azure.clientgenerator.core.override",
+  },
+  "azure/client-generator-core/hierarchy-building": {
+    namespace: "specs.azure.clientgenerator.core.hierarchybuilding",
+  },
+  "azure/core/basic": {
+    namespace: "specs.azure.core.basic",
+  },
+  "azure/core/lro/rpc": {
+    namespace: "specs.azure.core.lro.rpc",
+  },
+  "azure/core/lro/standard": {
+    namespace: "specs.azure.core.lro.standard",
+  },
+  "azure/core/model": {
+    namespace: "specs.azure.core.model",
+  },
+  "azure/core/page": {
+    namespace: "specs.azure.core.page",
+  },
+  "azure/core/scalar": {
+    namespace: "specs.azure.core.scalar",
+  },
+  "azure/core/traits": {
+    namespace: "specs.azure.core.traits",
+  },
+  "azure/encode/duration": {
+    namespace: "specs.azure.encode.duration",
+  },
+  "azure/example/basic": {
+    namespace: "specs.azure.example.basic",
+  },
+  "azure/payload/pageable": {
+    namespace: "specs.azure.payload.pageable",
+  },
+  "azure/versioning/previewVersion": {
+    namespace: "specs.azure.versioning.previewversion",
+  },
+  "client/structure/default": {
+    namespace: "client.structure.service",
+  },
+  "client/structure/multi-client": {
+    "package-name": "client-structure-multiclient",
+    namespace: "client.structure.multiclient",
+  },
+  "client/structure/renamed-operation": {
+    "package-name": "client-structure-renamedoperation",
+    namespace: "client.structure.renamedoperation",
+  },
+  "client/structure/two-operation-group": {
+    "package-name": "client-structure-twooperationgroup",
+    namespace: "client.structure.twooperationgroup",
+  },
+  "client/naming": {
+    namespace: "client.naming.main",
+  },
+  "client/overload": {
+    namespace: "client.overload",
+  },
+  "encode/duration": {
+    namespace: "encode.duration",
+  },
+  "encode/numeric": {
+    namespace: "encode.numeric",
+  },
+  "parameters/basic": {
+    namespace: "parameters.basic",
+  },
+  "parameters/spread": {
+    namespace: "parameters.spread",
+  },
+  "payload/content-negotiation": {
+    namespace: "payload.contentnegotiation",
+  },
+  "payload/multipart": {
+    namespace: "payload.multipart",
+  },
+  "serialization/encoded-name/json": {
+    namespace: "serialization.encodedname.json",
+  },
+  "special-words": {
+    namespace: "specialwords",
+  },
+  "service/multi-service": {
+    namespace: "service.multiservice",
+  },
   "client/structure/client-operation-group": {
     "package-name": "client-structure-clientoperationgroup",
     namespace: "client.structure.clientoperationgroup",
@@ -105,13 +227,254 @@ const AZURE_EMITTER_OPTIONS: Record<string, Record<string, string> | Record<stri
 };
 
 const EMITTER_OPTIONS: Record<string, Record<string, string> | Record<string, string>[]> = {
-  ...BASE_EMITTER_OPTIONS,
+  "resiliency/srv-driven/old.tsp": {
+    "package-name": "resiliency-srv-driven1",
+    namespace: "resiliency.srv.driven1",
+    "package-mode": "azure-dataplane",
+    "package-pprint-name": "ResiliencySrvDriven1",
+  },
+  "resiliency/srv-driven": {
+    "package-name": "resiliency-srv-driven2",
+    namespace: "resiliency.srv.driven2",
+    "package-mode": "azure-dataplane",
+    "package-pprint-name": "ResiliencySrvDriven2",
+  },
+  "authentication/api-key": {
+    "clear-output-folder": "true",
+  },
+  "authentication/http/custom": {
+    "package-name": "authentication-http-custom",
+    namespace: "authentication.http.custom",
+    "package-pprint-name": "Authentication Http Custom",
+  },
+  "authentication/union": [
+    {
+      "package-name": "authentication-union",
+      namespace: "authentication.union",
+    },
+    {
+      "package-name": "setuppy-authentication-union",
+      namespace: "setuppy.authentication.union",
+      "keep-setup-py": "true",
+    },
+  ],
   "type/array": {
     "package-name": "typetest-array",
     namespace: "typetest.array",
   },
+  "type/dictionary": {
+    "package-name": "typetest-dictionary",
+    namespace: "typetest.dictionary",
+  },
+  "type/enum/extensible": {
+    "package-name": "typetest-enum-extensible",
+    namespace: "typetest.enum.extensible",
+  },
+  "type/enum/fixed": {
+    "package-name": "typetest-enum-fixed",
+    namespace: "typetest.enum.fixed",
+  },
+  "type/model/empty": {
+    "package-name": "typetest-model-empty",
+    namespace: "typetest.model.empty",
+  },
+  "type/model/inheritance/enum-discriminator": {
+    "package-name": "typetest-model-enumdiscriminator",
+    namespace: "typetest.model.enumdiscriminator",
+  },
+  "type/model/inheritance/nested-discriminator": {
+    "package-name": "typetest-model-nesteddiscriminator",
+    namespace: "typetest.model.nesteddiscriminator",
+  },
+  "type/model/inheritance/not-discriminated": {
+    "package-name": "typetest-model-notdiscriminated",
+    namespace: "typetest.model.notdiscriminated",
+  },
+  "type/model/inheritance/single-discriminator": {
+    "package-name": "typetest-model-singlediscriminator",
+    namespace: "typetest.model.singlediscriminator",
+  },
+  "type/model/inheritance/recursive": [
+    {
+      "package-name": "typetest-model-recursive",
+      namespace: "typetest.model.recursive",
+    },
+    {
+      "package-name": "generation-subdir",
+      namespace: "generation.subdir",
+      "generation-subdir": "_generated",
+      "generate-test": "false",
+      "clear-output-folder": "true",
+    },
+  ],
+  "type/model/usage": {
+    "package-name": "typetest-model-usage",
+    namespace: "typetest.model.usage",
+  },
+  "type/model/visibility": [
+    {
+      "package-name": "typetest-model-visibility",
+      namespace: "typetest.model.visibility",
+    },
+    {
+      "package-name": "headasbooleantrue",
+      namespace: "headasbooleantrue",
+      "head-as-boolean": "true",
+    },
+    {
+      "package-name": "headasbooleanfalse",
+      namespace: "headasbooleanfalse",
+      "head-as-boolean": "false",
+    },
+  ],
+  "type/property/nullable": {
+    "package-name": "typetest-property-nullable",
+    namespace: "typetest.property.nullable",
+  },
+  "type/property/optionality": {
+    "package-name": "typetest-property-optional",
+    namespace: "typetest.property.optional",
+  },
+  "type/property/additional-properties": {
+    "package-name": "typetest-property-additionalproperties",
+    namespace: "typetest.property.additionalproperties",
+  },
+  "type/scalar": {
+    "package-name": "typetest-scalar",
+    namespace: "typetest.scalar",
+  },
+  "type/property/value-types": {
+    "package-name": "typetest-property-valuetypes",
+    namespace: "typetest.property.valuetypes",
+  },
+  "type/union": {
+    "package-name": "typetest-union",
+    namespace: "typetest.union",
+  },
+  "type/union/discriminated": {
+    "package-name": "typetest-discriminatedunion",
+    namespace: "typetest.discriminatedunion",
+  },
+  "type/file": {
+    "package-name": "typetest-file",
+    namespace: "typetest.file",
+  },
+  documentation: {
+    "package-name": "specs-documentation",
+    namespace: "specs.documentation",
+  },
+  "versioning/added": [
+    {
+      "package-name": "versioning-added",
+      namespace: "versioning.added",
+    },
+    {
+      "package-name": "generation-subdir2",
+      namespace: "generation.subdir2",
+      "generate-test": "false",
+      "generation-subdir": "_generated",
+    },
+  ],
 };
 
+// ---- Shared utility functions ----
+
+async function getSubdirectories(baseDir: string, flags: RegenerateFlags): Promise<string[]> {
+  const subdirectories: string[] = [];
+
+  async function searchDir(currentDir: string) {
+    const items = await readdir(currentDir, { withFileTypes: true });
+
+    const promisesArray = items.map(async (item) => {
+      const subDirPath = join(currentDir, item.name);
+      if (item.isDirectory()) {
+        const mainTspPath = join(subDirPath, "main.tsp");
+        const clientTspPath = join(subDirPath, "client.tsp");
+
+        const mainTspRelativePath = toPosix(relative(baseDir, mainTspPath));
+
+        if (SKIP_SPECS.some((skipSpec) => mainTspRelativePath.includes(skipSpec))) return;
+
+        const hasMainTsp = await access(mainTspPath)
+          .then(() => true)
+          .catch(() => false);
+        const hasClientTsp = await access(clientTspPath)
+          .then(() => true)
+          .catch(() => false);
+
+        if (mainTspRelativePath.toLowerCase().includes(flags.name || "")) {
+          if (mainTspRelativePath.includes("resiliency/srv-driven")) {
+            subdirectories.push(resolve(subDirPath, "old.tsp"));
+          }
+          if (hasClientTsp) {
+            subdirectories.push(resolve(subDirPath, "client.tsp"));
+          } else if (hasMainTsp) {
+            subdirectories.push(resolve(subDirPath, "main.tsp"));
+          }
+        }
+
+        await searchDir(subDirPath);
+      }
+    });
+
+    await Promise.all(promisesArray);
+  }
+
+  await searchDir(baseDir);
+  return subdirectories;
+}
+
+async function preprocess(flavor: string, generatedFolder: string): Promise<void> {
+  if (flavor === "azure") {
+    const testsGeneratedDir = resolve(generatedFolder, "../tests/generated/azure");
+
+    const DELETE_CONTENT = "# This file is to be deleted after regeneration";
+    const DELETE_FILE = "to_be_deleted.py";
+    const entries: { folder: string[]; file: string; content: string }[] = [
+      {
+        folder: ["authentication-api-key", "authentication", "apikey", "_operations"],
+        file: DELETE_FILE,
+        content: DELETE_CONTENT,
+      },
+      {
+        folder: ["generation-subdir", "generation", "subdir", "_generated"],
+        file: DELETE_FILE,
+        content: DELETE_CONTENT,
+      },
+      {
+        folder: ["generation-subdir", "generated_tests"],
+        file: DELETE_FILE,
+        content: DELETE_CONTENT,
+      },
+      {
+        folder: ["generation-subdir", "generation", "subdir"],
+        file: "to_be_kept.py",
+        content: "# This file is to be kept after regeneration",
+      },
+    ];
+
+    await Promise.all(
+      entries.map(async ({ folder, file, content }) => {
+        const targetFolder = join(testsGeneratedDir, ...folder);
+        await mkdir(targetFolder, { recursive: true });
+        await writeFile(join(targetFolder, file), content);
+      }),
+    );
+  }
+}
+
+// Get paths
+const SCRIPT_DIR = dirname(fileURLToPath(import.meta.url));
+const PLUGIN_DIR = argv.values.pluginDir
+  ? resolve(argv.values.pluginDir)
+  : resolve(SCRIPT_DIR, "../../../");
+const AZURE_HTTP_SPECS = resolve(PLUGIN_DIR, "node_modules/@azure-tools/azure-http-specs/specs");
+const HTTP_SPECS = resolve(PLUGIN_DIR, "node_modules/@typespec/http-specs/specs");
+const GENERATED_FOLDER = argv.values.generatedFolder
+  ? resolve(argv.values.generatedFolder)
+  : resolve(PLUGIN_DIR, "generator");
+const EMITTER_NAME = argv.values.emitterName || "@typespec/http-client-python";
+
 interface CompileTask {
   spec: string;
   outputDir: string;
@@ -124,15 +487,22 @@ interface TaskGroup {
   tasks: CompileTask[];
 }
 
+// Check whether a spec path belongs to azure-http-specs (vs standard http-specs).
+// Using "azure-http-specs" instead of "azure" to avoid false positives when the
+// working directory path contains "azure" (e.g. azure-sdk-for-python).
+function isAzureSpec(spec: string): boolean {
+  return spec.includes("azure-http-specs");
+}
+
 function defaultPackageName(spec: string): string {
-  const specDir = spec.includes("azure") ? AZURE_HTTP_SPECS : HTTP_SPECS;
+  const specDir = isAzureSpec(spec) ? AZURE_HTTP_SPECS : HTTP_SPECS;
   return toPosix(relative(specDir, dirname(spec)))
     .replace(/\//g, "-")
     .toLowerCase();
 }
 
 function getEmitterOptions(spec: string, flavor: string): Record<string, string>[] {
-  const specDir = spec.includes("azure") ? AZURE_HTTP_SPECS : HTTP_SPECS;
+  const specDir = isAzureSpec(spec) ? AZURE_HTTP_SPECS : HTTP_SPECS;
   const relativeSpec = toPosix(relative(specDir, spec));
   const key = relativeSpec.includes("resiliency/srv-driven/old.tsp")
     ? relativeSpec
@@ -262,7 +632,7 @@ async function runParallel(groups: TaskGroup[], maxJobs: number): Promise<Map<st
     // Each group runs as a unit - tasks within a group run sequentially
     // But different groups can run in parallel
     const runGroup = async () => {
-      const specDir = group.spec.includes("azure") ? AZURE_HTTP_SPECS : HTTP_SPECS;
+      const specDir = isAzureSpec(group.spec) ? AZURE_HTTP_SPECS : HTTP_SPECS;
       const shortName = toPosix(relative(specDir, dirname(group.spec)));
 
       // Run all tasks in this group sequentially to avoid state pollution
@@ -311,16 +681,19 @@ async function runParallel(groups: TaskGroup[], maxJobs: number): Promise<Map<st
   return results;
 }
 
-function collectConfigFiles(generatedDir: string, flavor: string): string[] {
+async function collectConfigFiles(generatedDir: string, flavor: string): Promise<string[]> {
   const flavorDir = join(generatedDir, "..", "tests", "generated", flavor);
-  if (!existsSync(flavorDir)) return [];
+  try {
+    await access(flavorDir);
+  } catch {
+    return [];
+  }
 
   const configFiles: string[] = [];
-  for (const pkg of readdirSync(flavorDir, { withFileTypes: true })) {
+  for (const pkg of await readdir(flavorDir, { withFileTypes: true })) {
     if (pkg.isDirectory()) {
       const pkgDir = join(flavorDir, pkg.name);
-      // Find all .tsp-codegen-*.json files (supports multiple configs per output dir)
-      for (const file of readdirSync(pkgDir)) {
+      for (const file of await readdir(pkgDir)) {
         if (file.startsWith(".tsp-codegen-") && file.endsWith(".json")) {
           configFiles.push(join(pkgDir, file));
         }
@@ -412,7 +785,7 @@ async function regenerateFlavor(
 
   // Batch process all specs with Python
   const pyStartTime = performance.now();
-  const configCount = collectConfigFiles(GENERATED_FOLDER, flavor).length;
+  const configCount = (await collectConfigFiles(GENERATED_FOLDER, flavor)).length;
   // Use fewer Python jobs since Python processing is heavier
   const pyJobs = Math.max(4, jobs);
   const pySuccess = runBatchPythonProcessing(flavor, configCount, pyJobs);