diff --git a/README.md b/README.md
index 5e50808..6de4f74 100644
--- a/README.md
+++ b/README.md
@@ -111,16 +111,21 @@ const response = await client.models();
 
 ## API
 
-- `chat()`
-- `models()`
-- `putFile()`
-- `putFileStream()`
-- `files()`
-- `getFile()`
-- `getFileContent()`
-- `deleteFile()`
-- `estimateTokenCount()`
-- `getBalance()`
+- Chat
+  - `chat()`
+  - `models()`
+  - `estimateTokenCount()`
+
+- Files
+  - `putFile()`
+  - `putFileStream()`
+  - `files()`
+  - `getFile()`
+  - `getFileContent()`
+  - `deleteFile()`
+
+- Others
+  - `getBalance()`
 
 The detail of parameters can be found at <https://platform.moonshot.cn/docs/api-reference> or [`test/kimi.test.js`](./test/kimi.test.js).
 
diff --git a/bin/kimi.js b/bin/kimi.js
index 106cba2..1d268b7 100755
--- a/bin/kimi.js
+++ b/bin/kimi.js
@@ -14,8 +14,9 @@ import Kimi from '../lib/kimi.js';
 import { loadConfig, saveConfig } from '../lib/config.js';
 
 const KIMI_RC_PATH = path.join(homedir(), '.moonshot_ai_rc');
+const rcPath = KIMI_RC_PATH;
 
-const config = await loadConfig(KIMI_RC_PATH);
+const config = await loadConfig(rcPath);
 
 async function question(prompt) {
   const answers = await inquirer.prompt([
@@ -57,7 +58,7 @@ async function chooseAPIKey() {
     mask: '*'
   });
   config.api_key = apikey.trim();
-  await saveConfig(config, KIMI_RC_PATH);
+  await saveConfig(config, rcPath);
 }
 
 if (!config.api_key) {
@@ -96,7 +97,7 @@ async function chooseModel() {
   if (model) {
     config.model = model;
   }
-  await saveConfig(config, KIMI_RC_PATH);
+  await saveConfig(config, rcPath);
 }
 
 if (!config.model) {
@@ -152,7 +153,7 @@ while (true) {
     });
 
     config.api_key = apikey;
-    await saveConfig(config, KIMI_RC_PATH);
+    await saveConfig(config, rcPath);
     console.log('The new API key is set.');
     continue;
   }
@@ -169,7 +170,7 @@ while (true) {
     });
 
     config.verbose = verbose === 'true';
-    await saveConfig(config, KIMI_RC_PATH);
+    await saveConfig(config, rcPath);
     console.log(`The verbose mode is turned ${config.verbose ? 'on' : 'off'} now.`);
     continue;
   }
diff --git a/lib/apikey.js b/lib/apikey.js
new file mode 100644
index 0000000..09e86a6
--- /dev/null
+++ b/lib/apikey.js
@@ -0,0 +1,18 @@
+import { homedir } from 'os';
+import { join } from 'path';
+import { loadConfig } from './config.js';
+
+const KIMI_RC_PATH = join(homedir(), '.moonshot_ai_rc');
+
+export async function getAPIKey(rcPath = KIMI_RC_PATH) {
+  if (process.env.MOONSHOT_API_KEY) {
+    return process.env.MOONSHOT_API_KEY;
+  }
+
+  const config = await loadConfig(rcPath);
+  if (config && config.api_key) {
+    return config.api_key;
+  }
+
+  return '';
+}