diff --git a/extensions/zai/index.ts b/extensions/zai/index.ts
index 109bf5144a1..33929645968 100644
--- a/extensions/zai/index.ts
+++ b/extensions/zai/index.ts
@@ -1,6 +1,3 @@
-import fs from "node:fs";
-import os from "node:os";
-import path from "node:path";
 import {
   emptyPluginConfigSchema,
   type OpenClawPluginApi,
@@ -10,7 +7,6 @@ import {
   type ProviderResolveDynamicModelContext,
   type ProviderRuntimeModel,
 } from "openclaw/plugin-sdk/core";
-import { resolveRequiredHomeDir } from "openclaw/plugin-sdk/infra-runtime";
 import {
   applyAuthProfileConfig,
   buildApiKeyCredential,
@@ -23,7 +19,7 @@ import {
 } from "openclaw/plugin-sdk/provider-auth";
 import { DEFAULT_CONTEXT_TOKENS, normalizeModelCompat } from "openclaw/plugin-sdk/provider-models";
 import { createZaiToolStreamWrapper } from "openclaw/plugin-sdk/provider-stream";
-import { fetchZaiUsage } from "openclaw/plugin-sdk/provider-usage";
+import { fetchZaiUsage, resolveLegacyPiAgentAccessToken } from "openclaw/plugin-sdk/provider-usage";
 import { detectZaiEndpoint, type ZaiEndpointId } from "./detect.js";
 import { zaiMediaUnderstandingProvider } from "./media-understanding-provider.js";
 import { applyZaiConfig, applyZaiProviderConfig, ZAI_DEFAULT_MODEL_REF } from "./onboard.js";
@@ -68,27 +64,6 @@ function resolveGlm5ForwardCompatModel(
   } as ProviderRuntimeModel);
 }
 
-function resolveLegacyZaiUsageToken(env: NodeJS.ProcessEnv): string | undefined {
-  try {
-    const authPath = path.join(
-      resolveRequiredHomeDir(env, os.homedir),
-      ".pi",
-      "agent",
-      "auth.json",
-    );
-    if (!fs.existsSync(authPath)) {
-      return undefined;
-    }
-    const parsed = JSON.parse(fs.readFileSync(authPath, "utf8")) as Record<
-      string,
-      { access?: string }
-    >;
-    return parsed["z-ai"]?.access || parsed.zai?.access;
-  } catch {
-    return undefined;
-  }
-}
-
 function resolveZaiDefaultModel(modelIdOverride?: string): string {
   return modelIdOverride ? `zai/${modelIdOverride}` : ZAI_DEFAULT_MODEL_REF;
 }
@@ -328,7 +303,7 @@ const zaiPlugin = {
         if (apiKey) {
           return { token: apiKey };
         }
-        const legacyToken = resolveLegacyZaiUsageToken(ctx.env);
+        const legacyToken = resolveLegacyPiAgentAccessToken(ctx.env, ["z-ai", "zai"]);
         return legacyToken ? { token: legacyToken } : null;
       },
       fetchUsageSnapshot: async (ctx) => await fetchZaiUsage(ctx.token, ctx.timeoutMs, ctx.fetchFn),
diff --git a/src/infra/provider-usage.auth.ts b/src/infra/provider-usage.auth.ts
index dc62cece821..982ffbc8be5 100644
--- a/src/infra/provider-usage.auth.ts
+++ b/src/infra/provider-usage.auth.ts
@@ -1,6 +1,3 @@
-import fs from "node:fs";
-import os from "node:os";
-import path from "node:path";
 import {
   dedupeProfileIds,
   ensureAuthProfileStore,
@@ -12,9 +9,9 @@ import { isNonSecretApiKeyMarker } from "../agents/model-auth-markers.js";
 import { resolveUsableCustomProviderApiKey } from "../agents/model-auth.js";
 import { normalizeProviderId } from "../agents/model-selection.js";
 import { loadConfig, type OpenClawConfig } from "../config/config.js";
-import { resolveRequiredHomeDir } from "../infra/home-dir.js";
 import { resolveProviderUsageAuthWithPlugin } from "../plugins/provider-runtime.js";
 import { normalizeSecretInput } from "../utils/normalize-secret-input.js";
+import { resolveLegacyPiAgentAccessToken } from "./provider-usage.shared.js";
 import type { UsageProviderId } from "./provider-usage.types.js";
 
 export type ProviderAuth = {
@@ -44,27 +41,6 @@ function parseGoogleUsageToken(apiKey: string): string {
   return apiKey;
 }
 
-function resolveLegacyZaiUsageToken(env: NodeJS.ProcessEnv): string | undefined {
-  try {
-    const authPath = path.join(
-      resolveRequiredHomeDir(env, os.homedir),
-      ".pi",
-      "agent",
-      "auth.json",
-    );
-    if (!fs.existsSync(authPath)) {
-      return undefined;
-    }
-    const parsed = JSON.parse(fs.readFileSync(authPath, "utf8")) as Record<
-      string,
-      { access?: string }
-    >;
-    return parsed["z-ai"]?.access || parsed.zai?.access;
-  } catch {
-    return undefined;
-  }
-}
-
 function resolveProviderApiKeyFromConfigAndStore(params: {
   state: UsageAuthState;
   providerIds: string[];
@@ -225,7 +201,7 @@ async function resolveProviderUsageAuthFallback(params: {
       if (apiKey) {
         return { provider: "zai", token: apiKey };
       }
-      const legacyToken = resolveLegacyZaiUsageToken(params.state.env);
+      const legacyToken = resolveLegacyPiAgentAccessToken(params.state.env, ["z-ai", "zai"]);
       return legacyToken ? { provider: "zai", token: legacyToken } : null;
     }
     case "minimax": {
diff --git a/src/infra/provider-usage.shared.test.ts b/src/infra/provider-usage.shared.test.ts
index 048352a183d..4f575f197ff 100644
--- a/src/infra/provider-usage.shared.test.ts
+++ b/src/infra/provider-usage.shared.test.ts
@@ -1,5 +1,13 @@
+import fs from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
 import { afterEach, describe, expect, it, vi } from "vitest";
-import { clampPercent, resolveUsageProviderId, withTimeout } from "./provider-usage.shared.js";
+import {
+  clampPercent,
+  resolveLegacyPiAgentAccessToken,
+  resolveUsageProviderId,
+  withTimeout,
+} from "./provider-usage.shared.js";
 
 describe("provider-usage.shared", () => {
   afterEach(() => {
@@ -52,4 +60,34 @@ describe("provider-usage.shared", () => {
 
     expect(clearTimeoutSpy).toHaveBeenCalledTimes(1);
   });
+
+  it("reads legacy pi auth tokens for known provider aliases", async () => {
+    const home = await fs.mkdtemp(path.join(os.tmpdir(), "openclaw-provider-usage-"));
+    await fs.mkdir(path.join(home, ".pi", "agent"), { recursive: true });
+    await fs.writeFile(
+      path.join(home, ".pi", "agent", "auth.json"),
+      `${JSON.stringify({ "z-ai": { access: "legacy-zai-key" } }, null, 2)}\n`,
+      "utf8",
+    );
+
+    try {
+      expect(resolveLegacyPiAgentAccessToken({ HOME: home }, ["z-ai", "zai"])).toBe(
+        "legacy-zai-key",
+      );
+    } finally {
+      await fs.rm(home, { recursive: true, force: true });
+    }
+  });
+
+  it("returns undefined for invalid legacy pi auth files", async () => {
+    const home = await fs.mkdtemp(path.join(os.tmpdir(), "openclaw-provider-usage-"));
+    await fs.mkdir(path.join(home, ".pi", "agent"), { recursive: true });
+    await fs.writeFile(path.join(home, ".pi", "agent", "auth.json"), "{not-json", "utf8");
+
+    try {
+      expect(resolveLegacyPiAgentAccessToken({ HOME: home }, ["z-ai", "zai"])).toBeUndefined();
+    } finally {
+      await fs.rm(home, { recursive: true, force: true });
+    }
+  });
 });
diff --git a/src/infra/provider-usage.shared.ts b/src/infra/provider-usage.shared.ts
index 6fa823db630..b801da4824c 100644
--- a/src/infra/provider-usage.shared.ts
+++ b/src/infra/provider-usage.shared.ts
@@ -1,4 +1,8 @@
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
 import { normalizeProviderId } from "../agents/model-selection.js";
+import { resolveRequiredHomeDir } from "./home-dir.js";
 import type { UsageProviderId } from "./provider-usage.types.js";
 
 export const DEFAULT_TIMEOUT_MS = 5000;
@@ -59,3 +63,33 @@ export const withTimeout = async <T>(work: Promise<T>, ms: number, fallback: T):
     }
   }
 };
+
+export function resolveLegacyPiAgentAccessToken(
+  env: NodeJS.ProcessEnv,
+  providerIds: string[],
+): string | undefined {
+  try {
+    const authPath = path.join(
+      resolveRequiredHomeDir(env, os.homedir),
+      ".pi",
+      "agent",
+      "auth.json",
+    );
+    if (!fs.existsSync(authPath)) {
+      return undefined;
+    }
+    const parsed = JSON.parse(fs.readFileSync(authPath, "utf8")) as Record<
+      string,
+      { access?: string }
+    >;
+    for (const providerId of providerIds) {
+      const token = parsed[providerId]?.access;
+      if (typeof token === "string" && token.trim()) {
+        return token;
+      }
+    }
+    return undefined;
+  } catch {
+    return undefined;
+  }
+}
diff --git a/src/plugin-sdk/provider-usage.ts b/src/plugin-sdk/provider-usage.ts
index 33757596965..9b63a53ea93 100644
--- a/src/plugin-sdk/provider-usage.ts
+++ b/src/plugin-sdk/provider-usage.ts
@@ -13,7 +13,11 @@ export {
   fetchMinimaxUsage,
   fetchZaiUsage,
 } from "../infra/provider-usage.fetch.js";
-export { clampPercent, PROVIDER_LABELS } from "../infra/provider-usage.shared.js";
+export {
+  clampPercent,
+  PROVIDER_LABELS,
+  resolveLegacyPiAgentAccessToken,
+} from "../infra/provider-usage.shared.js";
 export {
   buildUsageErrorSnapshot,
   buildUsageHttpErrorSnapshot,
diff --git a/src/plugins/contracts/runtime.contract.test.ts b/src/plugins/contracts/runtime.contract.test.ts
index 073ad01c960..87acf1f8a13 100644
--- a/src/plugins/contracts/runtime.contract.test.ts
+++ b/src/plugins/contracts/runtime.contract.test.ts
@@ -1,3 +1,6 @@
+import fs from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
 import { describe, expect, it, vi } from "vitest";
 import { createProviderUsageFetch, makeResponse } from "../../test-utils/provider-usage-fetch.js";
 import type { ProviderRuntimeModel } from "../types.js";
@@ -514,6 +517,33 @@ describe("provider runtime contract", () => {
       });
     });
 
+    it("falls back to legacy pi auth tokens for usage auth", async () => {
+      const provider = requireProvider("zai");
+      const home = await fs.mkdtemp(path.join(os.tmpdir(), "openclaw-zai-contract-"));
+      await fs.mkdir(path.join(home, ".pi", "agent"), { recursive: true });
+      await fs.writeFile(
+        path.join(home, ".pi", "agent", "auth.json"),
+        `${JSON.stringify({ "z-ai": { access: "legacy-zai-token" } }, null, 2)}\n`,
+        "utf8",
+      );
+
+      try {
+        await expect(
+          provider.resolveUsageAuth?.({
+            config: {} as never,
+            env: { HOME: home } as NodeJS.ProcessEnv,
+            provider: "zai",
+            resolveApiKeyFromConfigAndStore: () => undefined,
+            resolveOAuthToken: async () => null,
+          }),
+        ).resolves.toEqual({
+          token: "legacy-zai-token",
+        });
+      } finally {
+        await fs.rm(home, { recursive: true, force: true });
+      }
+    });
+
     it("owns usage snapshot fetching", async () => {
       const provider = requireProviderContractProvider("zai");
       const mockFetch = createProviderUsageFetch(async (url) => {