diff --git a/open-sse/config/audioRegistry.js b/open-sse/config/audioRegistry.ts
similarity index 83%
rename from open-sse/config/audioRegistry.js
rename to open-sse/config/audioRegistry.ts
index 5f7456b6a9..cf6e11e0b0 100644
--- a/open-sse/config/audioRegistry.js
+++ b/open-sse/config/audioRegistry.ts
@@ -6,7 +6,22 @@
  * - /v1/audio/speech (TTS API)
  */
 
-export const AUDIO_TRANSCRIPTION_PROVIDERS = {
+interface AudioModel {
+  id: string;
+  name: string;
+}
+
+interface AudioProvider {
+  id: string;
+  baseUrl: string;
+  authType: string;
+  authHeader: string;
+  format?: string;
+  async?: boolean;
+  models: AudioModel[];
+}
+
+export const AUDIO_TRANSCRIPTION_PROVIDERS: Record<string, AudioProvider> = {
   openai: {
     id: "openai",
     baseUrl: "https://api.openai.com/v1/audio/transcriptions",
@@ -57,7 +72,7 @@ export const AUDIO_TRANSCRIPTION_PROVIDERS = {
   },
 };
 
-export const AUDIO_SPEECH_PROVIDERS = {
+export const AUDIO_SPEECH_PROVIDERS: Record<string, AudioProvider> = {
   openai: {
     id: "openai",
     baseUrl: "https://api.openai.com/v1/audio/speech",
@@ -96,21 +111,21 @@ export const AUDIO_SPEECH_PROVIDERS = {
 /**
  * Get transcription provider config by ID
  */
-export function getTranscriptionProvider(providerId) {
+export function getTranscriptionProvider(providerId: string): AudioProvider | null {
   return AUDIO_TRANSCRIPTION_PROVIDERS[providerId] || null;
 }
 
 /**
  * Get speech provider config by ID
  */
-export function getSpeechProvider(providerId) {
+export function getSpeechProvider(providerId: string): AudioProvider | null {
   return AUDIO_SPEECH_PROVIDERS[providerId] || null;
 }
 
 /**
  * Parse audio model string (format: "provider/model" or just "model")
  */
-function parseAudioModel(modelStr, registry) {
+function parseAudioModel(modelStr: string | null, registry: Record<string, AudioProvider>): { provider: string | null; model: string | null } {
   if (!modelStr) return { provider: null, model: null };
 
   for (const [providerId, config] of Object.entries(registry)) {
@@ -128,11 +143,11 @@ function parseAudioModel(modelStr, registry) {
   return { provider: null, model: modelStr };
 }
 
-export function parseTranscriptionModel(modelStr) {
+export function parseTranscriptionModel(modelStr: string | null) {
   return parseAudioModel(modelStr, AUDIO_TRANSCRIPTION_PROVIDERS);
 }
 
-export function parseSpeechModel(modelStr) {
+export function parseSpeechModel(modelStr: string | null) {
   return parseAudioModel(modelStr, AUDIO_SPEECH_PROVIDERS);
 }
 
diff --git a/open-sse/config/codexInstructions.js b/open-sse/config/codexInstructions.ts
similarity index 100%
rename from open-sse/config/codexInstructions.js
rename to open-sse/config/codexInstructions.ts
diff --git a/open-sse/config/constants.js b/open-sse/config/constants.ts
similarity index 100%
rename from open-sse/config/constants.js
rename to open-sse/config/constants.ts
diff --git a/open-sse/config/credentialLoader.js b/open-sse/config/credentialLoader.ts
similarity index 100%
rename from open-sse/config/credentialLoader.js
rename to open-sse/config/credentialLoader.ts
diff --git a/open-sse/config/defaultThinkingSignature.js b/open-sse/config/defaultThinkingSignature.ts
similarity index 100%
rename from open-sse/config/defaultThinkingSignature.js
rename to open-sse/config/defaultThinkingSignature.ts
diff --git a/open-sse/config/embeddingRegistry.js b/open-sse/config/embeddingRegistry.ts
similarity index 100%
rename from open-sse/config/embeddingRegistry.js
rename to open-sse/config/embeddingRegistry.ts
diff --git a/open-sse/config/imageRegistry.js b/open-sse/config/imageRegistry.ts
similarity index 100%
rename from open-sse/config/imageRegistry.js
rename to open-sse/config/imageRegistry.ts
diff --git a/open-sse/config/moderationRegistry.js b/open-sse/config/moderationRegistry.ts
similarity index 100%
rename from open-sse/config/moderationRegistry.js
rename to open-sse/config/moderationRegistry.ts
diff --git a/open-sse/config/ollamaModels.js b/open-sse/config/ollamaModels.ts
similarity index 100%
rename from open-sse/config/ollamaModels.js
rename to open-sse/config/ollamaModels.ts
diff --git a/open-sse/config/providerModels.js b/open-sse/config/providerModels.ts
similarity index 100%
rename from open-sse/config/providerModels.js
rename to open-sse/config/providerModels.ts
diff --git a/open-sse/config/providerRegistry.js b/open-sse/config/providerRegistry.ts
similarity index 94%
rename from open-sse/config/providerRegistry.js
rename to open-sse/config/providerRegistry.ts
index 063c46abee..ecfc9db06e 100644
--- a/open-sse/config/providerRegistry.js
+++ b/open-sse/config/providerRegistry.ts
@@ -6,9 +6,51 @@
  * is auto-generated from this registry.
  */
 
+// ── Types ─────────────────────────────────────────────────────────────────
+
+export interface RegistryModel {
+  id: string;
+  name: string;
+  targetFormat?: string;
+}
+
+export interface RegistryOAuth {
+  clientIdEnv?: string;
+  clientIdDefault?: string;
+  clientSecretEnv?: string;
+  clientSecretDefault?: string;
+  tokenUrl?: string;
+  refreshUrl?: string;
+  authUrl?: string;
+  initiateUrl?: string;
+  pollUrlBase?: string;
+}
+
+export interface RegistryEntry {
+  id: string;
+  alias: string;
+  format: string;
+  executor: string;
+  baseUrl?: string;
+  baseUrls?: string[];
+  responsesBaseUrl?: string;
+  urlSuffix?: string;
+  urlBuilder?: (base: string, model: string, stream: boolean) => string;
+  authType: string;
+  authHeader: string;
+  authPrefix?: string;
+  headers?: Record<string, string>;
+  extraHeaders?: Record<string, string>;
+  oauth?: RegistryOAuth;
+  models: RegistryModel[];
+  chatPath?: string;
+  clientVersion?: string;
+  passthroughModels?: boolean;
+}
+
 // ── Registry ──────────────────────────────────────────────────────────────
 
-export const REGISTRY = {
+export const REGISTRY: Record<string, RegistryEntry> = {
   // ─── OAuth Providers ───────────────────────────────────────────────────
   claude: {
     id: "claude",
@@ -760,10 +802,10 @@ export const REGISTRY = {
 // ── Generator Functions ───────────────────────────────────────────────────
 
 /** Generate legacy PROVIDERS object shape for constants.js backward compatibility */
-export function generateLegacyProviders() {
-  const providers = {};
+export function generateLegacyProviders(): Record<string, any> {
+  const providers: Record<string, any> = {};
   for (const [id, entry] of Object.entries(REGISTRY)) {
-    const p = { format: entry.format };
+    const p: Record<string, any> = { format: entry.format };
 
     // URL(s)
     if (entry.baseUrls) {
@@ -808,8 +850,8 @@ export function generateLegacyProviders() {
 }
 
 /** Generate PROVIDER_MODELS map (alias → model list) */
-export function generateModels() {
-  const models = {};
+export function generateModels(): Record<string, RegistryModel[]> {
+  const models: Record<string, RegistryModel[]> = {};
   for (const entry of Object.values(REGISTRY)) {
     if (entry.models && entry.models.length > 0) {
       const key = entry.alias || entry.id;
@@ -823,8 +865,8 @@ export function generateModels() {
 }
 
 /** Generate PROVIDER_ID_TO_ALIAS map */
-export function generateAliasMap() {
-  const map = {};
+export function generateAliasMap(): Record<string, string> {
+  const map: Record<string, string> = {};
   for (const entry of Object.values(REGISTRY)) {
     map[entry.id] = entry.alias || entry.id;
   }
@@ -841,12 +883,12 @@ for (const entry of Object.values(REGISTRY)) {
 }
 
 /** Get registry entry by provider ID or alias */
-export function getRegistryEntry(provider) {
+export function getRegistryEntry(provider: string): RegistryEntry | null {
   return REGISTRY[provider] || _byAlias.get(provider) || null;
 }
 
 /** Get all registered provider IDs */
-export function getRegisteredProviders() {
+export function getRegisteredProviders(): string[] {
   return Object.keys(REGISTRY);
 }
 
@@ -856,7 +898,7 @@ export function getRegisteredProviders() {
  * @param {string} provider - Provider ID or alias
  * @returns {"oauth"|"apikey"}
  */
-export function getProviderCategory(provider) {
+export function getProviderCategory(provider: string): "oauth" | "apikey" {
   const entry = getRegistryEntry(provider);
   if (!entry) return "apikey"; // Safe default for unknown providers
   return entry.authType === "apikey" ? "apikey" : "oauth";
diff --git a/open-sse/config/rerankRegistry.js b/open-sse/config/rerankRegistry.ts
similarity index 100%
rename from open-sse/config/rerankRegistry.js
rename to open-sse/config/rerankRegistry.ts
diff --git a/open-sse/executors/antigravity.js b/open-sse/executors/antigravity.ts
similarity index 100%
rename from open-sse/executors/antigravity.js
rename to open-sse/executors/antigravity.ts
diff --git a/open-sse/executors/base.js b/open-sse/executors/base.ts
similarity index 97%
rename from open-sse/executors/base.js
rename to open-sse/executors/base.ts
index 9c0791e4b9..c55653bcb1 100644
--- a/open-sse/executors/base.js
+++ b/open-sse/executors/base.ts
@@ -6,7 +6,10 @@ import { HTTP_STATUS, FETCH_TIMEOUT_MS } from "../config/constants.js";
  * (buildUrl, buildHeaders, transformRequest, etc.) for each provider.
  */
 export class BaseExecutor {
-  constructor(provider, config) {
+  provider: any;
+  config: any;
+
+  constructor(provider: any, config: any) {
     this.provider = provider;
     this.config = config;
   }
@@ -96,7 +99,7 @@ export class BaseExecutor {
             ? AbortSignal.any([signal, timeoutSignal])
             : signal || timeoutSignal;
 
-        const fetchOptions = {
+        const fetchOptions: Record<string, any> = {
           method: "POST",
           headers,
           body: JSON.stringify(transformedBody),
diff --git a/open-sse/executors/codex.js b/open-sse/executors/codex.ts
similarity index 100%
rename from open-sse/executors/codex.js
rename to open-sse/executors/codex.ts
diff --git a/open-sse/executors/cursor.js b/open-sse/executors/cursor.ts
similarity index 99%
rename from open-sse/executors/cursor.js
rename to open-sse/executors/cursor.ts
index 7f9a018dc1..5782998ed9 100644
--- a/open-sse/executors/cursor.js
+++ b/open-sse/executors/cursor.ts
@@ -1,3 +1,4 @@
+declare var EdgeRuntime: any;
 /**
  * CursorExecutor — Handles communication with the Cursor IDE API.
  *
@@ -226,7 +227,7 @@ export class CursorExecutor extends BaseExecutor {
 
     return {
       status: response.status,
-      headers: Object.fromEntries(response.headers.entries()),
+      headers: Object.fromEntries((response.headers as any).entries()),
       body: Buffer.from(await response.arrayBuffer()),
     };
   }
@@ -290,7 +291,7 @@ export class CursorExecutor extends BaseExecutor {
     const transformedBody = this.transformRequest(model, body, stream, credentials);
 
     try {
-      const response = http2
+      const response: any = http2
         ? await this.makeHttp2Request(url, headers, transformedBody, signal)
         : await this.makeFetchRequest(url, headers, transformedBody, signal);
 
@@ -458,8 +459,7 @@ export class CursorExecutor extends BaseExecutor {
 
     console.log(`[CURSOR BUFFER] Final toolCalls count: ${toolCalls.length}`);
 
-    const message = {
-      role: "assistant",
+    const message: Record<string, any> = { role: "assistant",
       content: totalContent || null,
     };
 
diff --git a/open-sse/executors/default.js b/open-sse/executors/default.ts
similarity index 100%
rename from open-sse/executors/default.js
rename to open-sse/executors/default.ts
diff --git a/open-sse/executors/gemini-cli.js b/open-sse/executors/gemini-cli.ts
similarity index 100%
rename from open-sse/executors/gemini-cli.js
rename to open-sse/executors/gemini-cli.ts
diff --git a/open-sse/executors/github.js b/open-sse/executors/github.ts
similarity index 100%
rename from open-sse/executors/github.js
rename to open-sse/executors/github.ts
diff --git a/open-sse/executors/index.js b/open-sse/executors/index.ts
similarity index 100%
rename from open-sse/executors/index.js
rename to open-sse/executors/index.ts
diff --git a/open-sse/executors/kiro.js b/open-sse/executors/kiro.ts
similarity index 98%
rename from open-sse/executors/kiro.js
rename to open-sse/executors/kiro.ts
index a9fe3a670e..f48e326973 100644
--- a/open-sse/executors/kiro.js
+++ b/open-sse/executors/kiro.ts
@@ -83,8 +83,7 @@ export class KiroExecutor extends BaseExecutor {
     let chunkIndex = 0;
     const responseId = `chatcmpl-${Date.now()}`;
     const created = Math.floor(Date.now() / 1000);
-    const state = {
-      endDetected: false,
+    const state: Record<string, any> = { endDetected: false,
       finishEmitted: false,
       hasToolCalls: false,
       toolCallIndex: 0,
@@ -126,7 +125,7 @@ export class KiroExecutor extends BaseExecutor {
             const content = event.payload.content;
             state.totalContentLength += content.length;
 
-            const chunk = {
+            const chunk: Record<string, any> = {
               id: responseId,
               object: "chat.completion.chunk",
               created,
@@ -145,7 +144,7 @@ export class KiroExecutor extends BaseExecutor {
 
           // Handle codeEvent
           if (eventType === "codeEvent" && event.payload?.content) {
-            const chunk = {
+            const chunk: Record<string, any> = {
               id: responseId,
               object: "chat.completion.chunk",
               created,
@@ -257,7 +256,7 @@ export class KiroExecutor extends BaseExecutor {
 
           // Handle messageStopEvent
           if (eventType === "messageStopEvent") {
-            const chunk = {
+            const chunk: Record<string, any> = {
               id: responseId,
               object: "chat.completion.chunk",
               created,
@@ -330,7 +329,7 @@ export class KiroExecutor extends BaseExecutor {
               };
             }
 
-            const finishChunk = {
+            const finishChunk: Record<string, any> = {
               id: responseId,
               object: "chat.completion.chunk",
               created,
diff --git a/open-sse/handlers/audioSpeech.js b/open-sse/handlers/audioSpeech.ts
similarity index 93%
rename from open-sse/handlers/audioSpeech.js
rename to open-sse/handlers/audioSpeech.ts
index bb1196e299..05299f902c 100644
--- a/open-sse/handlers/audioSpeech.js
+++ b/open-sse/handlers/audioSpeech.ts
@@ -100,12 +100,13 @@ async function handleDeepgramSpeech(providerConfig, body, modelId, token) {
  * @param {Object} options.credentials - Provider credentials { apiKey }
  * @returns {Response}
  */
+/** @returns {Promise<any>} */
 export async function handleAudioSpeech({ body, credentials }) {
   if (!body.model) {
-    return errorResponse("model is required", 400);
+    return errorResponse(400, "model is required");
   }
   if (!body.input) {
-    return errorResponse("input is required", 400);
+    return errorResponse(400, "input is required");
   }
 
   const { provider: providerId, model: modelId } = parseSpeechModel(body.model);
@@ -113,14 +114,14 @@ export async function handleAudioSpeech({ body, credentials }) {
 
   if (!providerConfig) {
     return errorResponse(
-      `No speech provider found for model "${body.model}". Available: openai, hyperbolic, deepgram`,
-      400
+      400,
+      `No speech provider found for model "${body.model}". Available: openai, hyperbolic, deepgram`
     );
   }
 
   const token = credentials?.apiKey || credentials?.accessToken;
   if (!token) {
-    return errorResponse(`No credentials for speech provider: ${providerId}`, 401);
+    return errorResponse(401, `No credentials for speech provider: ${providerId}`);
   }
 
   try {
@@ -168,6 +169,6 @@ export async function handleAudioSpeech({ body, credentials }) {
       },
     });
   } catch (err) {
-    return errorResponse(`Speech request failed: ${err.message}`, 500);
+    return errorResponse(500, `Speech request failed: ${err.message}`);
   }
 }
diff --git a/open-sse/handlers/audioTranscription.js b/open-sse/handlers/audioTranscription.ts
similarity index 89%
rename from open-sse/handlers/audioTranscription.js
rename to open-sse/handlers/audioTranscription.ts
index c25eac19f3..3c511f738f 100644
--- a/open-sse/handlers/audioTranscription.js
+++ b/open-sse/handlers/audioTranscription.ts
@@ -129,11 +129,11 @@ async function handleAssemblyAITranscription(providerConfig, file, modelId, toke
     }
 
     if (result.status === "error") {
-      return errorResponse(result.error || "AssemblyAI transcription failed", 500);
+      return errorResponse(500, result.error || "AssemblyAI transcription failed");
     }
   }
 
-  return errorResponse("AssemblyAI transcription timed out after 120s", 504);
+  return errorResponse(504, "AssemblyAI transcription timed out after 120s");
 }
 
 /**
@@ -144,15 +144,16 @@ async function handleAssemblyAITranscription(providerConfig, file, modelId, toke
  * @param {Object} options.credentials - Provider credentials { apiKey }
  * @returns {Response}
  */
+/** @returns {Promise<any>} */
 export async function handleAudioTranscription({ formData, credentials }) {
   const model = formData.get("model");
   if (!model) {
-    return errorResponse("model is required", 400);
+    return errorResponse(400, "model is required");
   }
 
   const file = formData.get("file");
   if (!file) {
-    return errorResponse("file is required", 400);
+    return errorResponse(400, "file is required");
   }
 
   const { provider: providerId, model: modelId } = parseTranscriptionModel(model);
@@ -160,14 +161,14 @@ export async function handleAudioTranscription({ formData, credentials }) {
 
   if (!providerConfig) {
     return errorResponse(
-      `No transcription provider found for model "${model}". Available: openai, groq, deepgram, assemblyai`,
-      400
+      400,
+      `No transcription provider found for model "${model}". Available: openai, groq, deepgram, assemblyai`
     );
   }
 
   const token = credentials?.apiKey || credentials?.accessToken;
   if (!token) {
-    return errorResponse(`No credentials for transcription provider: ${providerId}`, 401);
+    return errorResponse(401, `No credentials for transcription provider: ${providerId}`);
   }
 
   // Route to provider-specific handler
@@ -181,7 +182,7 @@ export async function handleAudioTranscription({ formData, credentials }) {
 
   // Default: OpenAI/Groq-compatible multipart proxy
   const upstreamForm = new FormData();
-  upstreamForm.append("file", file, file.name || "audio.wav");
+  upstreamForm.append("file", /** @type {Blob} */ (file), /** @type {any} */ (file).name || "audio.wav");
   upstreamForm.append("model", modelId);
 
   // Forward optional parameters
@@ -194,7 +195,7 @@ export async function handleAudioTranscription({ formData, credentials }) {
   ]) {
     const val = formData.get(key);
     if (val !== null && val !== undefined) {
-      upstreamForm.append(key, val);
+      upstreamForm.append(key, /** @type {string} */ (val));
     }
   }
 
@@ -221,6 +222,6 @@ export async function handleAudioTranscription({ formData, credentials }) {
       headers: { "Content-Type": contentType, "Access-Control-Allow-Origin": "*" },
     });
   } catch (err) {
-    return errorResponse(`Transcription request failed: ${err.message}`, 500);
+    return errorResponse(500, `Transcription request failed: ${err.message}`);
   }
 }
diff --git a/open-sse/handlers/chatCore.js b/open-sse/handlers/chatCore.ts
similarity index 99%
rename from open-sse/handlers/chatCore.js
rename to open-sse/handlers/chatCore.ts
index d260159aaa..12a77e4c71 100644
--- a/open-sse/handlers/chatCore.js
+++ b/open-sse/handlers/chatCore.ts
@@ -52,6 +52,7 @@ import { createProgressTransform, wantsProgress } from "../utils/progressTracker
  * @param {string} options.connectionId - Connection ID for usage tracking
  * @param {object} options.apiKeyInfo - API key metadata for usage attribution
  */
+/** @param {any} options */
 export async function handleChatCore({
   body,
   modelInfo,
diff --git a/open-sse/handlers/embeddings.js b/open-sse/handlers/embeddings.ts
similarity index 99%
rename from open-sse/handlers/embeddings.js
rename to open-sse/handlers/embeddings.ts
index 871ee4d123..96ed05d955 100644
--- a/open-sse/handlers/embeddings.js
+++ b/open-sse/handlers/embeddings.ts
@@ -52,7 +52,7 @@ export async function handleEmbedding({ body, credentials, log }) {
   }
 
   // Build upstream request
-  const upstreamBody = {
+  const upstreamBody: Record<string, any> = {
     model: model,
     input: body.input,
   };
diff --git a/open-sse/handlers/imageGeneration.js b/open-sse/handlers/imageGeneration.ts
similarity index 99%
rename from open-sse/handlers/imageGeneration.js
rename to open-sse/handlers/imageGeneration.ts
index 4aed218826..71b50f5785 100644
--- a/open-sse/handlers/imageGeneration.js
+++ b/open-sse/handlers/imageGeneration.ts
@@ -232,7 +232,7 @@ async function handleOpenAIImageGeneration({
   };
 
   // Build upstream request (OpenAI-compatible format)
-  const upstreamBody = {
+  const upstreamBody: Record<string, any> = {
     model: model,
     prompt: body.prompt,
   };
diff --git a/open-sse/handlers/moderations.js b/open-sse/handlers/moderations.ts
similarity index 86%
rename from open-sse/handlers/moderations.js
rename to open-sse/handlers/moderations.ts
index 32509dada3..64bce58aba 100644
--- a/open-sse/handlers/moderations.js
+++ b/open-sse/handlers/moderations.ts
@@ -15,9 +15,10 @@ import { errorResponse } from "../utils/error.js";
  * @param {Object} options.credentials - Provider credentials { apiKey }
  * @returns {Response}
  */
+/** @returns {Promise<any>} */
 export async function handleModeration({ body, credentials }) {
   if (!body.input) {
-    return errorResponse("input is required", 400);
+    return errorResponse(400, "input is required");
   }
 
   // Default to latest moderation model
@@ -27,14 +28,14 @@ export async function handleModeration({ body, credentials }) {
 
   if (!providerConfig) {
     return errorResponse(
-      `No moderation provider found for model "${model}". Available: openai`,
-      400
+      400,
+      `No moderation provider found for model "${model}". Available: openai`
     );
   }
 
   const token = credentials?.apiKey || credentials?.accessToken;
   if (!token) {
-    return errorResponse(`No credentials for moderation provider: ${providerId}`, 401);
+    return errorResponse(401, `No credentials for moderation provider: ${providerId}`);
   }
 
   try {
@@ -63,6 +64,6 @@ export async function handleModeration({ body, credentials }) {
       headers: { "Access-Control-Allow-Origin": "*" },
     });
   } catch (err) {
-    return errorResponse(`Moderation request failed: ${err.message}`, 500);
+    return errorResponse(500, `Moderation request failed: ${err.message}`);
   }
 }
diff --git a/open-sse/handlers/rerank.js b/open-sse/handlers/rerank.ts
similarity index 88%
rename from open-sse/handlers/rerank.js
rename to open-sse/handlers/rerank.ts
index 7ec8abf6d0..5851f8d3b3 100644
--- a/open-sse/handlers/rerank.js
+++ b/open-sse/handlers/rerank.ts
@@ -69,6 +69,7 @@ function transformResponseFromProvider(providerConfig, data) {
  * @param {Object} options.credentials - Provider credentials { apiKey, accessToken }
  * @returns {Response}
  */
+/** @returns {Promise<any>} */
 export async function handleRerank({
   model,
   query,
@@ -77,10 +78,10 @@ export async function handleRerank({
   return_documents,
   credentials,
 }) {
-  if (!model) return errorResponse("model is required", 400);
-  if (!query) return errorResponse("query is required", 400);
+  if (!model) return errorResponse(400, "model is required");
+  if (!query) return errorResponse(400, "query is required");
   if (!documents || !Array.isArray(documents) || documents.length === 0) {
-    return errorResponse("documents must be a non-empty array", 400);
+    return errorResponse(400, "documents must be a non-empty array");
   }
 
   const { provider: providerId, model: modelId } = parseRerankModel(model);
@@ -88,14 +89,14 @@ export async function handleRerank({
 
   if (!providerConfig) {
     return errorResponse(
-      `No rerank provider found for model "${model}". Available: cohere, together, nvidia, fireworks`,
-      400
+      400,
+      `No rerank provider found for model "${model}". Available: cohere, together, nvidia, fireworks`
     );
   }
 
   const token = credentials?.apiKey || credentials?.accessToken;
   if (!token) {
-    return errorResponse(`No credentials for rerank provider: ${providerId}`, 401);
+    return errorResponse(401, `No credentials for rerank provider: ${providerId}`);
   }
 
   const requestBody = transformRequestForProvider(providerConfig, {
@@ -119,8 +120,8 @@ export async function handleRerank({
     if (!res.ok) {
       const errData = await res.json().catch(() => ({}));
       return errorResponse(
-        errData.message || errData.error?.message || `Provider returned HTTP ${res.status}`,
-        res.status
+        res.status,
+        errData.message || errData.error?.message || `Provider returned HTTP ${res.status}`
       );
     }
 
@@ -131,6 +132,6 @@ export async function handleRerank({
       headers: { "Access-Control-Allow-Origin": "*" },
     });
   } catch (err) {
-    return errorResponse(`Rerank request failed: ${err.message}`, 500);
+    return errorResponse(500, `Rerank request failed: ${err.message}`);
   }
 }
diff --git a/open-sse/handlers/responseTranslator.js b/open-sse/handlers/responseTranslator.ts
similarity index 96%
rename from open-sse/handlers/responseTranslator.js
rename to open-sse/handlers/responseTranslator.ts
index 79dc42b388..10e46a24de 100644
--- a/open-sse/handlers/responseTranslator.js
+++ b/open-sse/handlers/responseTranslator.ts
@@ -56,7 +56,7 @@ export function translateNonStreamingResponse(responseBody, targetFormat, source
       }
     }
 
-    const message = { role: "assistant" };
+    const message: Record<string, any> = { role: "assistant" };
     if (textContent) {
       message.content = textContent;
     }
@@ -74,7 +74,7 @@ export function translateNonStreamingResponse(responseBody, targetFormat, source
     const model = response?.model || responseBody?.model || "openai-responses";
     const finishReason = toolCalls.length > 0 ? "tool_calls" : "stop";
 
-    const result = {
+    const result: Record<string, any> = {
       id: `chatcmpl-${response?.id || Date.now()}`,
       object: "chat.completion",
       created: createdAt,
@@ -162,7 +162,7 @@ export function translateNonStreamingResponse(responseBody, targetFormat, source
     }
 
     // Build OpenAI format message
-    const message = { role: "assistant" };
+    const message: Record<string, any> = { role: "assistant" };
     if (textContent) {
       message.content = textContent;
     }
@@ -183,7 +183,7 @@ export function translateNonStreamingResponse(responseBody, targetFormat, source
       finishReason = "tool_calls";
     }
 
-    const result = {
+    const result: Record<string, any> = {
       id: `chatcmpl-${response.responseId || Date.now()}`,
       object: "chat.completion",
       created: Math.floor(new Date(response.createTime || Date.now()).getTime() / 1000),
@@ -241,7 +241,7 @@ export function translateNonStreamingResponse(responseBody, targetFormat, source
       }
     }
 
-    const message = { role: "assistant" };
+    const message: Record<string, any> = { role: "assistant" };
     if (textContent) {
       message.content = textContent;
     }
@@ -259,7 +259,7 @@ export function translateNonStreamingResponse(responseBody, targetFormat, source
     if (finishReason === "end_turn") finishReason = "stop";
     if (finishReason === "tool_use") finishReason = "tool_calls";
 
-    const result = {
+    const result: Record<string, any> = {
       id: `chatcmpl-${responseBody.id || Date.now()}`,
       object: "chat.completion",
       created: Math.floor(Date.now() / 1000),
diff --git a/open-sse/handlers/responsesHandler.js b/open-sse/handlers/responsesHandler.ts
similarity index 96%
rename from open-sse/handlers/responsesHandler.js
rename to open-sse/handlers/responsesHandler.ts
index 1066726ecd..3eaa34f373 100644
--- a/open-sse/handlers/responsesHandler.js
+++ b/open-sse/handlers/responsesHandler.ts
@@ -45,8 +45,11 @@ export async function handleResponsesCore({
     onCredentialsRefreshed,
     onRequestSuccess,
     onDisconnect,
+    clientRawRequest: null,
     connectionId,
-  });
+    userAgent: null,
+    comboName: null,
+  } as any);
 
   if (!result.success || !result.response) {
     return result;
diff --git a/open-sse/handlers/sseParser.js b/open-sse/handlers/sseParser.ts
similarity index 97%
rename from open-sse/handlers/sseParser.js
rename to open-sse/handlers/sseParser.ts
index 608f5c349e..43392904be 100644
--- a/open-sse/handlers/sseParser.js
+++ b/open-sse/handlers/sseParser.ts
@@ -44,15 +44,14 @@ export function parseSSEToOpenAIResponse(rawSSE, fallbackModel) {
     }
   }
 
-  const message = {
-    role: "assistant",
+  const message: Record<string, any> = { role: "assistant",
     content: contentParts.join(""),
   };
   if (reasoningParts.length > 0) {
     message.reasoning_content = reasoningParts.join("");
   }
 
-  const result = {
+  const result: Record<string, any> = {
     id: first.id || `chatcmpl-${Date.now()}`,
     object: "chat.completion",
     created: first.created || Math.floor(Date.now() / 1000),
diff --git a/open-sse/handlers/usageExtractor.js b/open-sse/handlers/usageExtractor.ts
similarity index 100%
rename from open-sse/handlers/usageExtractor.js
rename to open-sse/handlers/usageExtractor.ts
diff --git a/open-sse/index.js b/open-sse/index.ts
similarity index 100%
rename from open-sse/index.js
rename to open-sse/index.ts
diff --git a/open-sse/services/accountFallback.js b/open-sse/services/accountFallback.ts
similarity index 99%
rename from open-sse/services/accountFallback.js
rename to open-sse/services/accountFallback.ts
index c7bca2cd8d..59e2aed06d 100644
--- a/open-sse/services/accountFallback.js
+++ b/open-sse/services/accountFallback.ts
@@ -504,7 +504,7 @@ export function applyErrorState(account, status, errorText, provider = null) {
  * @param {object} account
  * @returns {number} score 0 = unhealthy, 100 = perfectly healthy
  */
-export function getAccountHealth(account) {
+export function getAccountHealth(account, model?: any) {
   if (!account) return 0;
   let score = 100;
   score -= (account.backoffLevel || 0) * 10;
diff --git a/open-sse/services/accountSelector.js b/open-sse/services/accountSelector.ts
similarity index 98%
rename from open-sse/services/accountSelector.js
rename to open-sse/services/accountSelector.ts
index a43886ed70..a4d392bb8c 100644
--- a/open-sse/services/accountSelector.js
+++ b/open-sse/services/accountSelector.ts
@@ -43,7 +43,7 @@ export function selectAccountP2C(accounts, model = null) {
  * @param {string} [model] - Model name
  * @returns {{ account: object|null, state: object }}
  */
-export function selectAccount(accounts, strategy = "fill-first", state = {}, model = null) {
+export function selectAccount(accounts, strategy = "fill-first", state: any = {}, model = null) {
   if (!accounts || accounts.length === 0) {
     return { account: null, state };
   }
diff --git a/open-sse/services/combo.js b/open-sse/services/combo.ts
similarity index 99%
rename from open-sse/services/combo.js
rename to open-sse/services/combo.ts
index 90e75de9af..5e0f33f9be 100644
--- a/open-sse/services/combo.js
+++ b/open-sse/services/combo.ts
@@ -221,6 +221,7 @@ function sortModelsByUsage(models, comboName) {
  * @param {Object} options.log - Logger object
  * @returns {Promise<Response>}
  */
+/** @param {any} options */
 export async function handleComboChat({
   body,
   combo,
diff --git a/open-sse/services/comboConfig.js b/open-sse/services/comboConfig.ts
similarity index 95%
rename from open-sse/services/comboConfig.js
rename to open-sse/services/comboConfig.ts
index 2e2ad77c7e..27519f10e7 100644
--- a/open-sse/services/comboConfig.js
+++ b/open-sse/services/comboConfig.ts
@@ -27,7 +27,7 @@ const DEFAULT_COMBO_CONFIG = {
  * @param {string} [provider] - Optional provider to apply provider-level overrides
  * @returns {Object} Resolved config
  */
-export function resolveComboConfig(combo, settings, provider) {
+export function resolveComboConfig(combo, settings, provider?: any) {
   const global = settings?.comboDefaults || {};
   const providerOverride = provider ? settings?.providerOverrides?.[provider] || {} : {};
   const comboConfig = combo?.config || {};
diff --git a/open-sse/services/comboMetrics.js b/open-sse/services/comboMetrics.ts
similarity index 93%
rename from open-sse/services/comboMetrics.js
rename to open-sse/services/comboMetrics.ts
index 021e913e74..0b1366595c 100644
--- a/open-sse/services/comboMetrics.js
+++ b/open-sse/services/comboMetrics.ts
@@ -35,7 +35,7 @@ export function recordComboRequest(
     });
   }
 
-  const combo = metrics.get(comboName);
+  const combo: any = metrics.get(comboName);
   combo.totalRequests++;
   combo.totalLatencyMs += latencyMs;
   combo.totalFallbacks += fallbackCount;
@@ -81,7 +81,7 @@ export function recordComboRequest(
  * @returns {Object|null}
  */
 export function getComboMetrics(comboName) {
-  const combo = metrics.get(comboName);
+  const combo: any = metrics.get(comboName);
   if (!combo) return null;
 
   return {
@@ -93,7 +93,7 @@ export function getComboMetrics(comboName) {
     fallbackRate:
       combo.totalRequests > 0 ? Math.round((combo.totalFallbacks / combo.totalRequests) * 100) : 0,
     byModel: Object.fromEntries(
-      Object.entries(combo.byModel).map(([model, m]) => [
+      Object.entries(combo.byModel).map(([model, m]: [string, any]) => [
         model,
         {
           ...m,
@@ -110,7 +110,7 @@ export function getComboMetrics(comboName) {
  * @returns {Object} Map of comboName → metrics
  */
 export function getAllComboMetrics() {
-  const result = {};
+  const result: Record<string, any> = {};
   for (const [name] of metrics) {
     result[name] = getComboMetrics(name);
   }
diff --git a/open-sse/services/contextManager.js b/open-sse/services/contextManager.ts
similarity index 99%
rename from open-sse/services/contextManager.js
rename to open-sse/services/contextManager.ts
index 373331ce63..1c2234a533 100644
--- a/open-sse/services/contextManager.js
+++ b/open-sse/services/contextManager.ts
@@ -51,7 +51,7 @@ export function getTokenLimit(provider, model = null) {
  * @param {object} options - { provider?, model?, maxTokens?, reserveTokens? }
  * @returns {{ body: object, compressed: boolean, stats: object }}
  */
-export function compressContext(body, options = {}) {
+export function compressContext(body, options: any = {}) {
   if (!body || !body.messages || !Array.isArray(body.messages)) {
     return { body, compressed: false, stats: {} };
   }
diff --git a/open-sse/services/ipFilter.js b/open-sse/services/ipFilter.ts
similarity index 100%
rename from open-sse/services/ipFilter.js
rename to open-sse/services/ipFilter.ts
diff --git a/open-sse/services/model.js b/open-sse/services/model.ts
similarity index 100%
rename from open-sse/services/model.js
rename to open-sse/services/model.ts
diff --git a/open-sse/services/provider.js b/open-sse/services/provider.ts
similarity index 99%
rename from open-sse/services/provider.js
rename to open-sse/services/provider.ts
index 5d640ba208..d0cce5260f 100644
--- a/open-sse/services/provider.js
+++ b/open-sse/services/provider.ts
@@ -156,7 +156,7 @@ export function getProviderFallbackCount(provider) {
 }
 
 // Build provider URL
-export function buildProviderUrl(provider, model, stream = true, options = {}) {
+export function buildProviderUrl(provider, model, stream = true, options: any = {}) {
   if (isOpenAICompatible(provider)) {
     const apiType = getOpenAICompatibleType(provider);
     const baseUrl = options?.baseUrl || OPENAI_COMPATIBLE_DEFAULTS.baseUrl;
diff --git a/open-sse/services/rateLimitManager.js b/open-sse/services/rateLimitManager.ts
similarity index 99%
rename from open-sse/services/rateLimitManager.js
rename to open-sse/services/rateLimitManager.ts
index 381d458e5c..42e261a164 100644
--- a/open-sse/services/rateLimitManager.js
+++ b/open-sse/services/rateLimitManager.ts
@@ -293,7 +293,7 @@ export function updateFromHeaders(provider, connectionId, headers, status, model
     // Calculate optimal minTime from RPM limit
     const minTime = Math.max(0, Math.floor(60000 / limit) - 10); // Small buffer
 
-    const updates = { minTime };
+    const updates: Record<string, any> = { minTime };
 
     // If remaining is low (< 10% of limit), set reservoir to throttle immediately
     if (!isNaN(remaining)) {
@@ -348,7 +348,7 @@ export function getRateLimitStatus(provider, connectionId) {
  * Get all active limiters status (for dashboard overview)
  */
 export function getAllRateLimitStatus() {
-  const result = {};
+  const result: Record<string, any> = {};
   for (const [key, limiter] of limiters) {
     const counts = limiter.counts();
     result[key] = {
diff --git a/open-sse/services/rateLimitSemaphore.js b/open-sse/services/rateLimitSemaphore.ts
similarity index 99%
rename from open-sse/services/rateLimitSemaphore.js
rename to open-sse/services/rateLimitSemaphore.ts
index b6c149321f..472c71bfae 100644
--- a/open-sse/services/rateLimitSemaphore.js
+++ b/open-sse/services/rateLimitSemaphore.ts
@@ -117,7 +117,7 @@ export function acquire(modelStr, { maxConcurrency = 3, timeoutMs = 30000 } = {}
       const idx = gate.queue.findIndex((item) => item.timer === timer);
       if (idx !== -1) gate.queue.splice(idx, 1);
       const err = new Error(`Semaphore timeout after ${timeoutMs}ms for ${modelStr}`);
-      err.code = "SEMAPHORE_TIMEOUT";
+      (err as any).code = "SEMAPHORE_TIMEOUT";
       reject(err);
     }, timeoutMs);
 
diff --git a/open-sse/services/sessionManager.js b/open-sse/services/sessionManager.ts
similarity index 98%
rename from open-sse/services/sessionManager.js
rename to open-sse/services/sessionManager.ts
index 11ffd11be3..b74580af88 100644
--- a/open-sse/services/sessionManager.js
+++ b/open-sse/services/sessionManager.ts
@@ -36,7 +36,7 @@ _cleanupTimer.unref();
  * @param {object} [options] - Extra context
  * @returns {string} Session ID (hex hash)
  */
-export function generateSessionId(body, options = {}) {
+export function generateSessionId(body, options: any = {}) {
   const parts = [];
 
   // Model contributes to fingerprint
diff --git a/open-sse/services/signatureCache.js b/open-sse/services/signatureCache.ts
similarity index 96%
rename from open-sse/services/signatureCache.js
rename to open-sse/services/signatureCache.ts
index 82b810bb26..a188dc261c 100644
--- a/open-sse/services/signatureCache.js
+++ b/open-sse/services/signatureCache.ts
@@ -34,7 +34,7 @@ const MAX_PATTERNS_PER_KEY = 50;
  * @param {object} context - { tool?, modelFamily?, sessionId? }
  * @returns {string[]} Array of unique signature patterns
  */
-export function getSignatures(context = {}) {
+export function getSignatures(context: any = {}) {
   const patterns = new Set(DEFAULT_SIGNATURES);
 
   // Layer 1: Tool (e.g., "cursor", "cline", "antigravity")
@@ -61,7 +61,7 @@ export function getSignatures(context = {}) {
  * @param {string} pattern - The signature pattern (e.g., "<antThinking>")
  * @param {object} context - { tool?, modelFamily?, sessionId? }
  */
-export function addSignature(pattern, context = {}) {
+export function addSignature(pattern: any, context: any = {}) {
   if (!pattern || typeof pattern !== "string") return;
 
   const addToLayer = (layer, key) => {
@@ -93,7 +93,7 @@ export function addSignature(pattern, context = {}) {
  * @param {object} context - { tool?, modelFamily?, sessionId? }
  * @returns {{ found: string[], cleaned: string }} Detected tags and cleaned text
  */
-export function detectAndLearn(text, context = {}) {
+export function detectAndLearn(text: any, context: any = {}) {
   if (!text || typeof text !== "string") return { found: [], cleaned: text };
 
   const found = [];
diff --git a/open-sse/services/systemPrompt.js b/open-sse/services/systemPrompt.ts
similarity index 100%
rename from open-sse/services/systemPrompt.js
rename to open-sse/services/systemPrompt.ts
diff --git a/open-sse/services/thinkingBudget.js b/open-sse/services/thinkingBudget.ts
similarity index 100%
rename from open-sse/services/thinkingBudget.js
rename to open-sse/services/thinkingBudget.ts
diff --git a/open-sse/services/tokenRefresh.js b/open-sse/services/tokenRefresh.ts
similarity index 100%
rename from open-sse/services/tokenRefresh.js
rename to open-sse/services/tokenRefresh.ts
diff --git a/open-sse/services/usage.js b/open-sse/services/usage.ts
similarity index 99%
rename from open-sse/services/usage.js
rename to open-sse/services/usage.ts
index 185dd9918d..cca9e702f9 100644
--- a/open-sse/services/usage.js
+++ b/open-sse/services/usage.ts
@@ -38,7 +38,7 @@ const CLAUDE_CONFIG = {
 /**
  * Get usage data for a provider connection
  * @param {Object} connection - Provider connection with accessToken
- * @returns {Object} Usage data with quotas
+ * @returns {Promise<any>} Usage data with quotas
  */
 export async function getUsageForProvider(connection) {
   const { provider, accessToken, providerSpecificData } = connection;
@@ -49,7 +49,7 @@ export async function getUsageForProvider(connection) {
     case "gemini-cli":
       return await getGeminiUsage(accessToken);
     case "antigravity":
-      return await getAntigravityUsage(accessToken);
+      return await getAntigravityUsage(accessToken, undefined);
     case "claude":
       return await getClaudeUsage(accessToken);
     case "codex":
@@ -311,7 +311,7 @@ async function getAntigravityUsage(accessToken, providerSpecificData) {
     }
 
     const data = await response.json();
-    const quotas = {};
+    const quotas: Record<string, any> = {};
 
     // Parse model quotas (inspired by vscode-antigravity-cockpit)
     if (data.models) {
@@ -328,7 +328,7 @@ async function getAntigravityUsage(accessToken, providerSpecificData) {
         "gemini-2.5-flash",
       ];
 
-      for (const [modelKey, info] of Object.entries(data.models)) {
+      for (const [modelKey, info] of Object.entries(data.models) as [string, any][]) {
         // Skip models without quota info
         if (!info.quotaInfo) {
           continue;
diff --git a/open-sse/services/wildcardRouter.js b/open-sse/services/wildcardRouter.ts
similarity index 100%
rename from open-sse/services/wildcardRouter.js
rename to open-sse/services/wildcardRouter.ts
diff --git a/open-sse/transformer/responsesTransformer.js b/open-sse/transformer/responsesTransformer.ts
similarity index 99%
rename from open-sse/transformer/responsesTransformer.js
rename to open-sse/transformer/responsesTransformer.ts
index e1c4318c20..f9e9aa23bb 100644
--- a/open-sse/transformer/responsesTransformer.js
+++ b/open-sse/transformer/responsesTransformer.ts
@@ -1,3 +1,5 @@
+import * as fs from 'fs';
+import * as path from 'path';
 /**
  * Responses API Transformer
  * Converts OpenAI Chat Completions SSE to Codex Responses API SSE format
diff --git a/open-sse/translator/formats.js b/open-sse/translator/formats.ts
similarity index 100%
rename from open-sse/translator/formats.js
rename to open-sse/translator/formats.ts
diff --git a/open-sse/translator/helpers/claudeHelper.js b/open-sse/translator/helpers/claudeHelper.ts
similarity index 100%
rename from open-sse/translator/helpers/claudeHelper.js
rename to open-sse/translator/helpers/claudeHelper.ts
diff --git a/open-sse/translator/helpers/geminiHelper.js b/open-sse/translator/helpers/geminiHelper.ts
similarity index 99%
rename from open-sse/translator/helpers/geminiHelper.js
rename to open-sse/translator/helpers/geminiHelper.ts
index 0b9241152f..63cee758b1 100644
--- a/open-sse/translator/helpers/geminiHelper.js
+++ b/open-sse/translator/helpers/geminiHelper.ts
@@ -193,7 +193,7 @@ function mergeAllOf(obj) {
   if (!obj || typeof obj !== "object") return;
 
   if (obj.allOf && Array.isArray(obj.allOf)) {
-    const merged = {};
+    const merged: Record<string, any> = {};
 
     for (const item of obj.allOf) {
       if (item.properties) {
diff --git a/open-sse/translator/helpers/maxTokensHelper.js b/open-sse/translator/helpers/maxTokensHelper.ts
similarity index 100%
rename from open-sse/translator/helpers/maxTokensHelper.js
rename to open-sse/translator/helpers/maxTokensHelper.ts
diff --git a/open-sse/translator/helpers/openaiHelper.js b/open-sse/translator/helpers/openaiHelper.ts
similarity index 100%
rename from open-sse/translator/helpers/openaiHelper.js
rename to open-sse/translator/helpers/openaiHelper.ts
diff --git a/open-sse/translator/helpers/responsesApiHelper.js b/open-sse/translator/helpers/responsesApiHelper.ts
similarity index 100%
rename from open-sse/translator/helpers/responsesApiHelper.js
rename to open-sse/translator/helpers/responsesApiHelper.ts
diff --git a/open-sse/translator/helpers/toolCallHelper.js b/open-sse/translator/helpers/toolCallHelper.ts
similarity index 100%
rename from open-sse/translator/helpers/toolCallHelper.js
rename to open-sse/translator/helpers/toolCallHelper.ts
diff --git a/open-sse/translator/index.js b/open-sse/translator/index.ts
similarity index 99%
rename from open-sse/translator/index.js
rename to open-sse/translator/index.ts
index 3215da0ce9..78731d640f 100644
--- a/open-sse/translator/index.js
+++ b/open-sse/translator/index.ts
@@ -234,7 +234,7 @@ export function translateResponse(targetFormat, sourceFormat, chunk, state) {
 
   // Attach OpenAI intermediate results for logging
   if (openaiResults && sourceFormat !== FORMATS.OPENAI && targetFormat !== FORMATS.OPENAI) {
-    results._openaiIntermediate = openaiResults;
+    (results as any)._openaiIntermediate = openaiResults;
   }
 
   return results;
diff --git a/open-sse/translator/request/antigravity-to-openai.js b/open-sse/translator/request/antigravity-to-openai.ts
similarity index 97%
rename from open-sse/translator/request/antigravity-to-openai.js
rename to open-sse/translator/request/antigravity-to-openai.ts
index 4a6402d17e..859051f3e9 100644
--- a/open-sse/translator/request/antigravity-to-openai.js
+++ b/open-sse/translator/request/antigravity-to-openai.ts
@@ -6,7 +6,7 @@ import { adjustMaxTokens } from "../helpers/maxTokensHelper.js";
 // Antigravity body: { project, model, userAgent, requestType, requestId, request: { contents, systemInstruction, tools, toolConfig, generationConfig, sessionId } }
 export function antigravityToOpenAIRequest(model, body, stream) {
   const req = body.request || body;
-  const result = {
+  const result: Record<string, any> = {
     model: model,
     messages: [],
     stream: stream,
@@ -190,7 +190,7 @@ function convertContent(content) {
 
   // Assistant with tool calls
   if (toolCalls.length > 0) {
-    const msg = { role: "assistant" };
+    const msg: Record<string, any> = { role: "assistant" };
     if (textParts.length > 0) {
       msg.content =
         textParts.length === 1 && textParts[0].type === "text" ? textParts[0].text : textParts;
@@ -204,7 +204,7 @@ function convertContent(content) {
 
   // Regular message
   if (textParts.length > 0 || reasoningContent) {
-    const msg = { role };
+    const msg: Record<string, any> = { role };
     if (textParts.length > 0) {
       msg.content =
         textParts.length === 1 && textParts[0].type === "text" ? textParts[0].text : textParts;
diff --git a/open-sse/translator/request/claude-to-gemini.js b/open-sse/translator/request/claude-to-gemini.ts
similarity index 99%
rename from open-sse/translator/request/claude-to-gemini.js
rename to open-sse/translator/request/claude-to-gemini.ts
index 3b5c7f21ba..a2ddf9ace6 100644
--- a/open-sse/translator/request/claude-to-gemini.js
+++ b/open-sse/translator/request/claude-to-gemini.ts
@@ -9,7 +9,7 @@ import { DEFAULT_THINKING_GEMINI_SIGNATURE } from "../../config/defaultThinkingS
  * skipping the OpenAI hub intermediate step.
  */
 export function claudeToGeminiRequest(model, body, stream) {
-  const result = {
+  const result: Record<string, any> = {
     model: model,
     contents: [],
     generationConfig: {},
diff --git a/open-sse/translator/request/claude-to-openai.js b/open-sse/translator/request/claude-to-openai.ts
similarity index 98%
rename from open-sse/translator/request/claude-to-openai.js
rename to open-sse/translator/request/claude-to-openai.ts
index 040b54d2ae..65d5be281b 100644
--- a/open-sse/translator/request/claude-to-openai.js
+++ b/open-sse/translator/request/claude-to-openai.ts
@@ -4,7 +4,7 @@ import { adjustMaxTokens } from "../helpers/maxTokensHelper.js";
 
 // Convert Claude request to OpenAI format
 export function claudeToOpenAIRequest(model, body, stream) {
-  const result = {
+  const result: Record<string, any> = {
     model: model,
     messages: [],
     stream: stream,
@@ -186,7 +186,7 @@ function convertClaudeMessage(msg) {
 
     // If has tool calls, return assistant message with tool_calls
     if (toolCalls.length > 0) {
-      const result = { role: "assistant" };
+      const result: Record<string, any> = { role: "assistant" };
       if (parts.length > 0) {
         result.content = parts.length === 1 && parts[0].type === "text" ? parts[0].text : parts;
       }
diff --git a/open-sse/translator/request/gemini-to-openai.js b/open-sse/translator/request/gemini-to-openai.ts
similarity index 97%
rename from open-sse/translator/request/gemini-to-openai.js
rename to open-sse/translator/request/gemini-to-openai.ts
index ad067e070e..13a46d0c56 100644
--- a/open-sse/translator/request/gemini-to-openai.js
+++ b/open-sse/translator/request/gemini-to-openai.ts
@@ -4,7 +4,7 @@ import { adjustMaxTokens } from "../helpers/maxTokensHelper.js";
 
 // Convert Gemini request to OpenAI format
 export function geminiToOpenAIRequest(model, body, stream) {
-  const result = {
+  const result: Record<string, any> = {
     model: model,
     messages: [],
     stream: stream,
@@ -116,7 +116,7 @@ function convertGeminiContent(content) {
   }
 
   if (toolCalls.length > 0) {
-    const result = { role: "assistant" };
+    const result: Record<string, any> = { role: "assistant" };
     if (parts.length > 0) {
       result.content = parts.length === 1 ? parts[0].text : parts;
     }
diff --git a/open-sse/translator/request/openai-responses.js b/open-sse/translator/request/openai-responses.ts
similarity index 97%
rename from open-sse/translator/request/openai-responses.js
rename to open-sse/translator/request/openai-responses.ts
index c3176ee2d4..1ac99d36ec 100644
--- a/open-sse/translator/request/openai-responses.js
+++ b/open-sse/translator/request/openai-responses.ts
@@ -21,8 +21,8 @@ export function openaiResponsesToOpenAIRequest(model, body, stream, credentials)
         const error = new Error(
           `Unsupported Responses API feature: ${tool.type} tool type is not supported by omniroute`
         );
-        error.statusCode = 400;
-        error.errorType = "unsupported_feature";
+        (error as any).statusCode = 400;
+        (error as any).errorType = "unsupported_feature";
         throw error;
       }
     }
@@ -31,12 +31,12 @@ export function openaiResponsesToOpenAIRequest(model, body, stream, credentials)
     const error = new Error(
       "Unsupported Responses API feature: background mode is not supported by omniroute"
     );
-    error.statusCode = 400;
-    error.errorType = "unsupported_feature";
+    (error as any).statusCode = 400;
+    (error as any).errorType = "unsupported_feature";
     throw error;
   }
 
-  const result = { ...body };
+  const result: Record<string, any> = { ...body };
   result.messages = [];
 
   // Convert instructions to system message
@@ -159,7 +159,7 @@ export function openaiResponsesToOpenAIRequest(model, body, stream, credentials)
  * Convert OpenAI Chat Completions to OpenAI Responses API format
  */
 export function openaiToOpenAIResponsesRequest(model, body, stream, credentials) {
-  const result = {
+  const result: Record<string, any> = {
     model,
     input: [],
     stream: true,
diff --git a/open-sse/translator/request/openai-to-claude.js b/open-sse/translator/request/openai-to-claude.ts
similarity index 99%
rename from open-sse/translator/request/openai-to-claude.js
rename to open-sse/translator/request/openai-to-claude.ts
index 5a2ccb3b0a..62aac8e6f8 100644
--- a/open-sse/translator/request/openai-to-claude.js
+++ b/open-sse/translator/request/openai-to-claude.ts
@@ -11,7 +11,7 @@ const CLAUDE_OAUTH_TOOL_PREFIX = "proxy_";
 export function openaiToClaudeRequest(model, body, stream) {
   // Tool name mapping for Claude OAuth (capitalizedName → originalName)
   const toolNameMap = new Map();
-  const result = {
+  const result: Record<string, any> = {
     model: model,
     max_tokens: adjustMaxTokens(body),
     stream: stream,
diff --git a/open-sse/translator/request/openai-to-cursor.js b/open-sse/translator/request/openai-to-cursor.ts
similarity index 95%
rename from open-sse/translator/request/openai-to-cursor.js
rename to open-sse/translator/request/openai-to-cursor.ts
index e8e7485dfc..6228257957 100644
--- a/open-sse/translator/request/openai-to-cursor.js
+++ b/open-sse/translator/request/openai-to-cursor.ts
@@ -66,7 +66,7 @@ function convertMessages(messages) {
 
       // Keep tool_calls structure for assistant messages
       if (msg.role === "assistant" && msg.tool_calls && msg.tool_calls.length > 0) {
-        const assistantMsg = { role: "assistant" };
+        const assistantMsg: Record<string, any> = { role: "assistant" };
         if (content) {
           assistantMsg.content = content;
         }
@@ -80,8 +80,7 @@ function convertMessages(messages) {
 
         result.push(assistantMsg);
       } else if (content || pendingToolResults.length > 0) {
-        const msgObj = {
-          role: msg.role,
+        const msgObj: Record<string, any> = { role: msg.role,
           content: content || "",
         };
 
diff --git a/open-sse/translator/request/openai-to-gemini.js b/open-sse/translator/request/openai-to-gemini.ts
similarity index 98%
rename from open-sse/translator/request/openai-to-gemini.js
rename to open-sse/translator/request/openai-to-gemini.ts
index 3945852499..d9dc479d23 100644
--- a/open-sse/translator/request/openai-to-gemini.js
+++ b/open-sse/translator/request/openai-to-gemini.ts
@@ -21,7 +21,7 @@ import {
 
 // Core: Convert OpenAI request to Gemini format (base for all variants)
 function openaiToGeminiBase(model, body, stream) {
-  const result = {
+  const result: Record<string, any> = {
     model: model,
     contents: [],
     generationConfig: {},
@@ -253,7 +253,7 @@ export function openaiToGeminiCLIRequest(model, body, stream) {
 function wrapInCloudCodeEnvelope(model, geminiCLI, credentials = null, isAntigravity = false) {
   const projectId = credentials?.projectId || generateProjectId();
 
-  const envelope = {
+  const envelope: Record<string, any> = {
     project: projectId,
     model: model,
     userAgent: isAntigravity ? "antigravity" : "gemini-cli",
@@ -272,7 +272,7 @@ function wrapInCloudCodeEnvelope(model, geminiCLI, credentials = null, isAntigra
     envelope.requestType = "agent";
 
     // Inject required default system prompt for Antigravity
-    const defaultPart = { text: ANTIGRAVITY_DEFAULT_SYSTEM };
+    const defaultPart: Record<string, any> = { text: ANTIGRAVITY_DEFAULT_SYSTEM };
     if (envelope.request.systemInstruction?.parts) {
       envelope.request.systemInstruction.parts.unshift(defaultPart);
     } else {
@@ -297,7 +297,7 @@ function wrapInCloudCodeEnvelope(model, geminiCLI, credentials = null, isAntigra
 function wrapInCloudCodeEnvelopeForClaude(model, claudeRequest, credentials = null) {
   const projectId = credentials?.projectId || generateProjectId();
 
-  const envelope = {
+  const envelope: Record<string, any> = {
     project: projectId,
     model: model,
     userAgent: "antigravity",
diff --git a/open-sse/translator/request/openai-to-kiro.js b/open-sse/translator/request/openai-to-kiro.ts
similarity index 99%
rename from open-sse/translator/request/openai-to-kiro.js
rename to open-sse/translator/request/openai-to-kiro.ts
index 8529b2cf3f..7bb5e6c43e 100644
--- a/open-sse/translator/request/openai-to-kiro.js
+++ b/open-sse/translator/request/openai-to-kiro.ts
@@ -22,7 +22,7 @@ function convertMessages(messages, tools, model) {
   const flushPending = () => {
     if (currentRole === "user") {
       const content = pendingUserContent.join("\n\n").trim() || "continue";
-      const userMsg = {
+      const userMsg: Record<string, any> = {
         userInputMessage: {
           content: content,
           modelId: "",
@@ -255,7 +255,7 @@ export function buildKiroPayload(model, body, stream, credentials) {
   const timestamp = new Date().toISOString();
   finalContent = `[Context: Current time is ${timestamp}]\n\n${finalContent}`;
 
-  const payload = {
+  const payload: Record<string, any> = {
     conversationState: {
       chatTriggerType: "MANUAL",
       conversationId: uuidv4(),
diff --git a/open-sse/translator/response/claude-to-openai.js b/open-sse/translator/response/claude-to-openai.ts
similarity index 99%
rename from open-sse/translator/response/claude-to-openai.js
rename to open-sse/translator/response/claude-to-openai.ts
index 57e5f9f9b9..47cb022f70 100644
--- a/open-sse/translator/response/claude-to-openai.js
+++ b/open-sse/translator/response/claude-to-openai.ts
@@ -133,7 +133,7 @@ export function claudeToOpenAIResponse(chunk, state) {
 
       if (chunk.delta?.stop_reason) {
         state.finishReason = convertStopReason(chunk.delta.stop_reason);
-        const finalChunk = {
+        const finalChunk: Record<string, any> = {
           id: `chatcmpl-${state.messageId}`,
           object: "chat.completion.chunk",
           created: Math.floor(Date.now() / 1000),
diff --git a/open-sse/translator/response/cursor-to-openai.js b/open-sse/translator/response/cursor-to-openai.ts
similarity index 100%
rename from open-sse/translator/response/cursor-to-openai.js
rename to open-sse/translator/response/cursor-to-openai.ts
diff --git a/open-sse/translator/response/gemini-to-claude.js b/open-sse/translator/response/gemini-to-claude.ts
similarity index 100%
rename from open-sse/translator/response/gemini-to-claude.js
rename to open-sse/translator/response/gemini-to-claude.ts
diff --git a/open-sse/translator/response/gemini-to-openai.js b/open-sse/translator/response/gemini-to-openai.ts
similarity index 99%
rename from open-sse/translator/response/gemini-to-openai.js
rename to open-sse/translator/response/gemini-to-openai.ts
index a678618b8d..8e57ffefc8 100644
--- a/open-sse/translator/response/gemini-to-openai.js
+++ b/open-sse/translator/response/gemini-to-openai.ts
@@ -226,7 +226,7 @@ export function geminiToOpenAIResponse(chunk, state) {
       finishReason = "tool_calls";
     }
 
-    const finalChunk = {
+    const finalChunk: Record<string, any> = {
       id: `chatcmpl-${state.messageId}`,
       object: "chat.completion.chunk",
       created: Math.floor(Date.now() / 1000),
diff --git a/open-sse/translator/response/kiro-to-openai.js b/open-sse/translator/response/kiro-to-openai.ts
similarity index 99%
rename from open-sse/translator/response/kiro-to-openai.js
rename to open-sse/translator/response/kiro-to-openai.ts
index 5e9e8a840d..969595b01b 100644
--- a/open-sse/translator/response/kiro-to-openai.js
+++ b/open-sse/translator/response/kiro-to-openai.ts
@@ -155,7 +155,7 @@ export function convertKiroToOpenAI(chunk, state) {
   if (eventType === "messageStopEvent" || eventType === "done" || data.messageStopEvent) {
     state.finishReason = "stop"; // Mark for usage injection in stream.js
 
-    const openaiChunk = {
+    const openaiChunk: Record<string, any> = {
       id: state.responseId,
       object: "chat.completion.chunk",
       created: state.created,
diff --git a/open-sse/translator/response/openai-responses.js b/open-sse/translator/response/openai-responses.ts
similarity index 99%
rename from open-sse/translator/response/openai-responses.js
rename to open-sse/translator/response/openai-responses.ts
index bd4efa4a0e..417a133bd9 100644
--- a/open-sse/translator/response/openai-responses.js
+++ b/open-sse/translator/response/openai-responses.ts
@@ -519,7 +519,7 @@ export function openaiResponsesToOpenAIResponse(chunk, state) {
       state.finishReasonSent = true;
       state.finishReason = "stop"; // Mark for usage injection in stream.js
 
-      const finalChunk = {
+      const finalChunk: Record<string, any> = {
         id: state.chatId,
         object: "chat.completion.chunk",
         created: state.created,
diff --git a/open-sse/translator/response/openai-to-antigravity.js b/open-sse/translator/response/openai-to-antigravity.ts
similarity index 96%
rename from open-sse/translator/response/openai-to-antigravity.js
rename to open-sse/translator/response/openai-to-antigravity.ts
index 30bee0ac54..82f17bedac 100644
--- a/open-sse/translator/response/openai-to-antigravity.js
+++ b/open-sse/translator/response/openai-to-antigravity.ts
@@ -81,7 +81,7 @@ export function openaiToAntigravityResponse(chunk, state) {
   }
 
   // Build candidate
-  const candidate = { content: { role: "model", parts } };
+  const candidate: Record<string, any> = { content: { role: "model", parts } };
 
   // Finish reason mapping
   if (finishReason) {
@@ -95,7 +95,7 @@ export function openaiToAntigravityResponse(chunk, state) {
   }
 
   // Build response
-  const response = {
+  const response: Record<string, any> = {
     candidates: [candidate],
     modelVersion: state._modelVersion,
     responseId: state._responseId,
diff --git a/open-sse/translator/response/openai-to-claude.js b/open-sse/translator/response/openai-to-claude.ts
similarity index 100%
rename from open-sse/translator/response/openai-to-claude.js
rename to open-sse/translator/response/openai-to-claude.ts
diff --git a/open-sse/tsconfig.json b/open-sse/tsconfig.json
new file mode 100644
index 0000000000..bffe1dbf28
--- /dev/null
+++ b/open-sse/tsconfig.json
@@ -0,0 +1,25 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "esnext",
+    "moduleResolution": "bundler",
+    "allowJs": true,
+    "checkJs": true,
+    "noEmit": true,
+    "skipLibCheck": true,
+    "esModuleInterop": true,
+    "strict": false,
+    "jsx": "react-jsx",
+    "lib": ["dom", "esnext"],
+    "baseUrl": "..",
+    "paths": {
+      "@/*": ["./src/*"],
+      "@omniroute/open-sse": ["./open-sse"],
+      "@omniroute/open-sse/*": ["./open-sse/*"]
+    }
+  },
+  "include": [
+    "**/*.ts",
+    "**/*.js"
+  ]
+}
diff --git a/open-sse/utils/bypassHandler.js b/open-sse/utils/bypassHandler.ts
similarity index 100%
rename from open-sse/utils/bypassHandler.js
rename to open-sse/utils/bypassHandler.ts
diff --git a/open-sse/utils/cursorChecksum.js b/open-sse/utils/cursorChecksum.ts
similarity index 100%
rename from open-sse/utils/cursorChecksum.js
rename to open-sse/utils/cursorChecksum.ts
diff --git a/open-sse/utils/cursorProtobuf.js b/open-sse/utils/cursorProtobuf.ts
similarity index 100%
rename from open-sse/utils/cursorProtobuf.js
rename to open-sse/utils/cursorProtobuf.ts
diff --git a/open-sse/utils/error.js b/open-sse/utils/error.ts
similarity index 96%
rename from open-sse/utils/error.js
rename to open-sse/utils/error.ts
index 12888e057d..0787c0face 100644
--- a/open-sse/utils/error.js
+++ b/open-sse/utils/error.ts
@@ -131,8 +131,8 @@ export async function parseUpstreamError(response, provider = null) {
  * @param {number|null} retryAfterMs - Optional retry-after time in milliseconds
  * @returns {{ success: false, status: number, error: string, response: Response, retryAfterMs?: number }}
  */
-export function createErrorResult(statusCode, message, retryAfterMs = null) {
-  const result = {
+export function createErrorResult(statusCode: number, message: string, retryAfterMs: number | null = null) {
+  const result: Record<string, any> = {
     success: false,
     status: statusCode,
     error: message,
@@ -155,7 +155,7 @@ export function createErrorResult(statusCode, message, retryAfterMs = null) {
  * @param {string} retryAfterHuman - Human-readable retry info e.g. "reset after 30s"
  * @returns {Response}
  */
-export function unavailableResponse(statusCode, message, retryAfter, retryAfterHuman) {
+export function unavailableResponse(statusCode, message, retryAfter?: any, retryAfterHuman?: any) {
   const retryAfterSec = Math.max(
     Math.ceil((new Date(retryAfter).getTime() - Date.now()) / 1000),
     1
diff --git a/open-sse/utils/logger.js b/open-sse/utils/logger.ts
similarity index 98%
rename from open-sse/utils/logger.js
rename to open-sse/utils/logger.ts
index eca067b9f8..ab205c9c6b 100644
--- a/open-sse/utils/logger.js
+++ b/open-sse/utils/logger.ts
@@ -96,7 +96,7 @@ export function logger(tag) {
     const consoleFn = getConsoleFn(level);
 
     if (jsonFormat) {
-      const entry = {
+      const entry: Record<string, any> = {
         ts: new Date().toISOString(),
         level,
         tag,
@@ -132,7 +132,7 @@ export function createLogger(requestId = null) {
     const consoleFn = getConsoleFn(level);
 
     if (jsonFormat) {
-      const entry = {
+      const entry: Record<string, any> = {
         ts: new Date().toISOString(),
         level,
         tag,
diff --git a/open-sse/utils/networkProxy.js b/open-sse/utils/networkProxy.ts
similarity index 98%
rename from open-sse/utils/networkProxy.js
rename to open-sse/utils/networkProxy.ts
index 9fbc3ea28e..b0c4e33058 100644
--- a/open-sse/utils/networkProxy.js
+++ b/open-sse/utils/networkProxy.ts
@@ -34,6 +34,7 @@ async function getConfig() {
  * @param {string} providerId - Provider ID (e.g., "openai", "anthropic")
  * @returns {string|null} Proxy URL or null if no proxy configured
  */
+/** @returns {Promise<any>} */
 export async function resolveProxy(providerId) {
   const config = await getConfig();
 
diff --git a/open-sse/utils/ollamaTransform.js b/open-sse/utils/ollamaTransform.ts
similarity index 96%
rename from open-sse/utils/ollamaTransform.js
rename to open-sse/utils/ollamaTransform.ts
index 6f1c788ec9..a993d081af 100644
--- a/open-sse/utils/ollamaTransform.js
+++ b/open-sse/utils/ollamaTransform.ts
@@ -1,7 +1,7 @@
 // Transform OpenAI SSE stream to Ollama JSON lines format
 export function transformToOllama(response, model) {
   let buffer = "";
-  let pendingToolCalls = {};
+  let pendingToolCalls: Record<number, any> = {};
 
   const transform = new TransformStream({
     transform(chunk, controller) {
@@ -51,7 +51,7 @@ export function transformToOllama(response, model) {
           if (finishReason === "tool_calls" || finishReason === "stop") {
             const toolCallsArr = Object.values(pendingToolCalls);
             if (toolCallsArr.length > 0) {
-              const formattedCalls = toolCallsArr.map((tc) => ({
+              const formattedCalls = toolCallsArr.map((tc: any) => ({
                 function: {
                   name: tc.function.name,
                   arguments: JSON.parse(tc.function.arguments || "{}"),
diff --git a/open-sse/utils/progressTracker.js b/open-sse/utils/progressTracker.ts
similarity index 97%
rename from open-sse/utils/progressTracker.js
rename to open-sse/utils/progressTracker.ts
index d42dcdd612..20845c390d 100644
--- a/open-sse/utils/progressTracker.js
+++ b/open-sse/utils/progressTracker.ts
@@ -21,7 +21,7 @@ const DEFAULT_INTERVAL_MS = 2000;
  * @param {AbortSignal} [options.signal] - Abort signal for cancellation
  * @returns {TransformStream}
  */
-export function createProgressTransform({ intervalMs = DEFAULT_INTERVAL_MS, signal } = {}) {
+export function createProgressTransform({ intervalMs = DEFAULT_INTERVAL_MS, signal }: { intervalMs?: number; signal?: AbortSignal } = {}) {
   let tokenCount = 0;
   let startTime = Date.now();
   let intervalId;
diff --git a/open-sse/utils/proxyDispatcher.js b/open-sse/utils/proxyDispatcher.ts
similarity index 97%
rename from open-sse/utils/proxyDispatcher.js
rename to open-sse/utils/proxyDispatcher.ts
index 0a4f235e1c..e82b279e73 100644
--- a/open-sse/utils/proxyDispatcher.js
+++ b/open-sse/utils/proxyDispatcher.ts
@@ -112,14 +112,14 @@ export function createProxyDispatcher(proxyUrl) {
 
   const parsed = new URL(normalizedUrl);
   if (parsed.protocol === "socks5:") {
-    const socksOptions = {
+    const socksOptions: Record<string, any> = {
       type: 5,
       host: parsed.hostname,
       port: Number(normalizePort(parsed.port, parsed.protocol)),
     };
     if (parsed.username) socksOptions.userId = decodeURIComponent(parsed.username);
     if (parsed.password) socksOptions.password = decodeURIComponent(parsed.password);
-    dispatcher = socksDispatcher(socksOptions);
+    dispatcher = socksDispatcher(socksOptions as any);
   } else {
     dispatcher = new ProxyAgent(normalizedUrl);
   }
diff --git a/open-sse/utils/proxyFetch.js b/open-sse/utils/proxyFetch.ts
similarity index 96%
rename from open-sse/utils/proxyFetch.js
rename to open-sse/utils/proxyFetch.ts
index 92a62c7497..5bcce7a285 100644
--- a/open-sse/utils/proxyFetch.js
+++ b/open-sse/utils/proxyFetch.ts
@@ -126,7 +126,7 @@ export async function runWithProxyContext(proxyConfig, fn) {
   });
 }
 
-async function patchedFetch(input, options = {}) {
+async function patchedFetch(input: any, options: any = {}) {
   if (options?.dispatcher) {
     return originalFetch(input, options);
   }
@@ -146,7 +146,7 @@ async function patchedFetch(input, options = {}) {
     // TLS fingerprint spoofing for direct connections (no proxy configured)
     if (isTlsFingerprintEnabled() && tlsClient.available) {
       try {
-        const store = tlsFingerprintContext.getStore();
+        const store: any = tlsFingerprintContext.getStore();
         if (store) store.used = true;
         return await tlsClient.fetch(targetUrl, options);
       } catch (error) {
@@ -154,7 +154,7 @@ async function patchedFetch(input, options = {}) {
         console.warn(
           `[ProxyFetch] TLS fingerprint failed, falling back to native fetch: ${message}`
         );
-        const store = tlsFingerprintContext.getStore();
+        const store: any = tlsFingerprintContext.getStore();
         if (store) store.used = false;
       }
     }
diff --git a/open-sse/utils/requestLogger.js b/open-sse/utils/requestLogger.ts
similarity index 100%
rename from open-sse/utils/requestLogger.js
rename to open-sse/utils/requestLogger.ts
diff --git a/open-sse/utils/stream.js b/open-sse/utils/stream.ts
similarity index 97%
rename from open-sse/utils/stream.js
rename to open-sse/utils/stream.ts
index c4e4d896a4..7e910b5c5a 100644
--- a/open-sse/utils/stream.js
+++ b/open-sse/utils/stream.ts
@@ -44,13 +44,15 @@ const STREAM_MODE = {
  * @param {object} options.body - Request body (for input token estimation)
  * @param {function} options.onComplete - Callback when stream finishes: ({ status, usage }) => void
  */
-export function createSSEStream(options = {}) {
+/** @param {any} options */
+export function createSSEStream(options: any = {}) {
   const {
     mode = STREAM_MODE.TRANSLATE,
     targetFormat,
     sourceFormat,
     provider = null,
     reqLogger = null,
+    /** @type {any} */
     toolNameMap = null,
     model = null,
     connectionId = null,
@@ -231,8 +233,8 @@ export function createSSEStream(options = {}) {
           const translated = translateResponse(targetFormat, sourceFormat, parsed, state);
 
           // Log OpenAI intermediate chunks (if available)
-          if (translated?._openaiIntermediate) {
-            for (const item of translated._openaiIntermediate) {
+          if ((translated as any)?._openaiIntermediate) {
+            for (const item of (translated as any)._openaiIntermediate) {
               const openaiOutput = formatSSE(item, FORMATS.OPENAI);
               reqLogger?.appendOpenAIChunk?.(openaiOutput);
             }
@@ -327,8 +329,8 @@ export function createSSEStream(options = {}) {
               const translated = translateResponse(targetFormat, sourceFormat, parsed, state);
 
               // Log OpenAI intermediate chunks
-              if (translated?._openaiIntermediate) {
-                for (const item of translated._openaiIntermediate) {
+              if ((translated as any)?._openaiIntermediate) {
+                for (const item of (translated as any)._openaiIntermediate) {
                   const openaiOutput = formatSSE(item, FORMATS.OPENAI);
                   reqLogger?.appendOpenAIChunk?.(openaiOutput);
                 }
@@ -348,8 +350,8 @@ export function createSSEStream(options = {}) {
           const flushed = translateResponse(targetFormat, sourceFormat, null, state);
 
           // Log OpenAI intermediate chunks for flushed events
-          if (flushed?._openaiIntermediate) {
-            for (const item of flushed._openaiIntermediate) {
+          if ((flushed as any)?._openaiIntermediate) {
+            for (const item of (flushed as any)._openaiIntermediate) {
               const openaiOutput = formatSSE(item, FORMATS.OPENAI);
               reqLogger?.appendOpenAIChunk?.(openaiOutput);
             }
diff --git a/open-sse/utils/streamHandler.js b/open-sse/utils/streamHandler.ts
similarity index 98%
rename from open-sse/utils/streamHandler.js
rename to open-sse/utils/streamHandler.ts
index 2f6bffe144..ff92aa5cbf 100644
--- a/open-sse/utils/streamHandler.js
+++ b/open-sse/utils/streamHandler.ts
@@ -18,7 +18,8 @@ function getTimeString() {
  * @param {string} options.provider - Provider name
  * @param {string} options.model - Model name
  */
-export function createStreamController({ onDisconnect, log, provider, model } = {}) {
+/** @param {any} options */
+export function createStreamController({ onDisconnect, log, provider, model }: any = {}) {
   const abortController = new AbortController();
   const startTime = Date.now();
   let disconnected = false;
diff --git a/open-sse/utils/streamHelpers.js b/open-sse/utils/streamHelpers.ts
similarity index 100%
rename from open-sse/utils/streamHelpers.js
rename to open-sse/utils/streamHelpers.ts
diff --git a/open-sse/utils/thinkTagParser.js b/open-sse/utils/thinkTagParser.ts
similarity index 100%
rename from open-sse/utils/thinkTagParser.js
rename to open-sse/utils/thinkTagParser.ts
diff --git a/open-sse/utils/tlsClient.js b/open-sse/utils/tlsClient.ts
similarity index 84%
rename from open-sse/utils/tlsClient.js
rename to open-sse/utils/tlsClient.ts
index a8e08b4268..5894179557 100644
--- a/open-sse/utils/tlsClient.js
+++ b/open-sse/utils/tlsClient.ts
@@ -2,7 +2,7 @@ import { createRequire } from "module";
 
 const require = createRequire(import.meta.url);
 
-let createSession;
+let createSession: any;
 try {
   ({ createSession } = require("wreq-js"));
 } catch {
@@ -13,7 +13,7 @@ try {
  * Get proxy URL from environment variables.
  * Priority: HTTPS_PROXY > HTTP_PROXY > ALL_PROXY
  */
-function getProxyFromEnv() {
+function getProxyFromEnv(): string | undefined {
   return (
     process.env.HTTPS_PROXY ||
     process.env.https_proxy ||
@@ -25,6 +25,14 @@ function getProxyFromEnv() {
   );
 }
 
+interface FetchOptions {
+  method?: string;
+  headers?: Record<string, string>;
+  body?: any;
+  redirect?: string;
+  signal?: AbortSignal;
+}
+
 /**
  * TLS Client — Chrome 124 TLS fingerprint spoofing via wreq-js
  * Singleton instance used to disguise Node.js TLS handshake as Chrome browser.
@@ -33,8 +41,10 @@ function getProxyFromEnv() {
  * Proxy URL is read from environment variables (HTTPS_PROXY, HTTP_PROXY, ALL_PROXY).
  */
 class TlsClient {
+  session: any = null;
+  available: boolean;
+
   constructor() {
-    this.session = null;
     this.available = !!createSession;
   }
 
@@ -43,7 +53,7 @@ class TlsClient {
     if (this.session) return this.session;
 
     const proxy = getProxyFromEnv();
-    const sessionOpts = {
+    const sessionOpts: Record<string, any> = {
       browser: "chrome_124",
       os: "macos",
     };
@@ -61,13 +71,13 @@ class TlsClient {
    * Fetch with Chrome 124 TLS fingerprint.
    * wreq-js Response is already fetch-compatible (headers, text(), json(), clone(), body).
    */
-  async fetch(url, options = {}) {
+  async fetch(url: string, options: FetchOptions = {}) {
     const session = await this.getSession();
     if (!session) throw new Error("wreq-js not available");
 
     const method = (options.method || "GET").toUpperCase();
 
-    const wreqOptions = {
+    const wreqOptions: Record<string, any> = {
       method,
       headers: options.headers,
       body: options.body,
@@ -92,3 +102,4 @@ class TlsClient {
 }
 
 export default new TlsClient();
+
diff --git a/open-sse/utils/usageTracking.js b/open-sse/utils/usageTracking.ts
similarity index 100%
rename from open-sse/utils/usageTracking.js
rename to open-sse/utils/usageTracking.ts
diff --git a/package-lock.json b/package-lock.json
index b4f8dbddad..f128d8b998 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "omniroute",
-  "version": "0.8.0",
+  "version": "0.8.5",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "omniroute",
-      "version": "0.8.0",
+      "version": "0.8.5",
       "license": "MIT",
       "workspaces": [
         "open-sse"
diff --git a/package.json b/package.json
index 9bb0cfff30..f3379e97fe 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "omniroute",
-  "version": "0.8.0",
+  "version": "0.8.5",
   "description": "Smart AI Router with auto fallback — route to FREE & cheap models, zero downtime. Works with Cursor, Cline, Claude Desktop, Codex, and any OpenAI-compatible tool.",
   "type": "module",
   "bin": {