1 files changed, 61 insertions, 52 deletions

diff --git a/packages/openai-stream/src/provider.ts b/packages/openai-stream/src/provider.ts
index c13d60e..9a9369f 100644
--- a/packages/openai-stream/src/provider.ts
+++ b/packages/openai-stream/src/provider.ts
@@ -1,12 +1,14 @@
 import type {
-	ApiKeyCredentials,
-	ChatMessage,
-	ModelInfo,
-	ProviderContract,
-	ProviderStreamOptions,
-	ToolContract,
+  ApiKeyCredentials,
+  ChatMessage,
+  ModelInfo,
+  ProviderContract,
+  ProviderStreamOptions,
+  ProviderUsage,
+  ToolContract,
 } from "@dispatch/kernel";
 import type { FetchLike } from "@dispatch/trace-replay";
+import { getUsage as fetchUsage } from "./getUsage.js";
 import { listModels as fetchModels } from "./listModels.js";
 import { streamChat } from "./stream.js";
 
@@ -19,55 +21,62 @@ import { streamChat } from "./stream.js";
  */
 
 export interface CreateOpenAICompatProviderOpts {
-	readonly credentials: ApiKeyCredentials;
-	readonly model: string;
-	/** Provider id (was hardcoded "openai-compat"). Stamped on the ProviderContract.id
-	 *  + used in listModels error labels. */
-	readonly id: string;
-	/**
-	 * Internal injectable fetch — used by tests and replay mode.
-	 * When absent, falls back to globalThis.fetch (production default).
-	 */
-	readonly fetchFn?: FetchLike;
-	/**
-	 * Optional hook a provider extension uses to add provider-specific body fields (e.g.
-	 * `reasoning_effort`) before the request is sent. Receives the body built so far +
-	 * the ProviderStreamOptions; returns ADDITIONAL fields to merge (or the full body).
-	 * Default (absent): no extra fields. Generic — the library names no feature.
-	 */
-	readonly transformBody?: (
-		body: Record<string, unknown>,
-		opts: ProviderStreamOptions,
-	) => Record<string, unknown>;
+  readonly credentials: ApiKeyCredentials;
+  readonly model: string;
+  /** Provider id (was hardcoded "openai-compat"). Stamped on the ProviderContract.id
+   *  + used in listModels error labels. */
+  readonly id: string;
+  /**
+   * Internal injectable fetch — used by tests and replay mode.
+   * When absent, falls back to globalThis.fetch (production default).
+   */
+  readonly fetchFn?: FetchLike;
+  /**
+   * Optional hook a provider extension uses to add provider-specific body fields (e.g.
+   * `reasoning_effort`) before the request is sent. Receives the body built so far +
+   * the ProviderStreamOptions; returns ADDITIONAL fields to merge (or the full body).
+   * Default (absent): no extra fields. Generic — the library names no feature.
+   */
+  readonly transformBody?: (
+    body: Record<string, unknown>,
+    opts: ProviderStreamOptions,
+  ) => Record<string, unknown>;
 }
 
 export function createOpenAICompatProvider(opts: CreateOpenAICompatProviderOpts): ProviderContract {
-	const baseURL = opts.credentials.baseURL ?? "https://opencode.ai/zen/go/v1";
-	const apiKey = opts.credentials.apiKey;
-	const fetchFn = opts.fetchFn;
-	const transformBody = opts.transformBody;
+  const baseURL = opts.credentials.baseURL ?? "https://opencode.ai/zen/go/v1";
+  const apiKey = opts.credentials.apiKey;
+  const fetchFn = opts.fetchFn;
+  const transformBody = opts.transformBody;
 
-	const streamConfig = {
-		baseURL,
-		apiKey,
-		model: opts.model,
-		...(fetchFn !== undefined ? { fetchFn } : {}),
-		...(transformBody !== undefined ? { transformBody } : {}),
-	};
+  const streamConfig = {
+    baseURL,
+    apiKey,
+    model: opts.model,
+    ...(fetchFn !== undefined ? { fetchFn } : {}),
+    ...(transformBody !== undefined ? { transformBody } : {}),
+  };
 
-	return {
-		id: opts.id,
-		stream: (
-			messages: readonly ChatMessage[],
-			tools: readonly ToolContract[],
-			streamOpts?: ProviderStreamOptions,
-		) => streamChat(streamConfig, messages, tools, streamOpts),
-		listModels: (): Promise<readonly ModelInfo[]> =>
-			fetchModels({
-				baseURL,
-				apiKey,
-				providerId: opts.id,
-				...(fetchFn !== undefined ? { fetchFn } : {}),
-			}),
-	};
+  return {
+    id: opts.id,
+    stream: (
+      messages: readonly ChatMessage[],
+      tools: readonly ToolContract[],
+      streamOpts?: ProviderStreamOptions,
+    ) => streamChat(streamConfig, messages, tools, streamOpts),
+    listModels: (): Promise<readonly ModelInfo[]> =>
+      fetchModels({
+        baseURL,
+        apiKey,
+        providerId: opts.id,
+        ...(fetchFn !== undefined ? { fetchFn } : {}),
+      }),
+    getUsage: (): Promise<ProviderUsage | undefined> =>
+      fetchUsage({
+        baseURL,
+        apiKey,
+        providerId: opts.id,
+        ...(fetchFn !== undefined ? { fetchFn } : {}),
+      }),
+  };
 }