diff --git a/docs/cli-design.md b/docs/cli-design.md
index 420a09f..a281ab7 100644
--- a/docs/cli-design.md
+++ b/docs/cli-design.md
@@ -52,10 +52,12 @@ mmx
 ## Authentication
 
 Credential resolution order:
-1. `--api-key` flag
-2. `$MINIMAX_API_KEY` env var
-3. `~/.mmx/credentials.json` (OAuth)
-4. `api_key` in `~/.mmx/config.yaml`
+1. `--api-key` flag (highest priority)
+2. `~/.mmx/credentials.json` (OAuth token — only created by `mmx auth login` without `--api-key`)
+3. `fileApiKey` in `~/.mmx/config.json` (persisted API key from a previous `mmx auth login --api-key`)
+
+If none are found, the CLI returns `No credentials found`. The `~/.mmx/credentials.json` file
+is **not required** when using API key auth — it is only created during OAuth login.
 
 ## Configuration
 
diff --git a/skill/SKILL.md b/skill/SKILL.md
index 7f64e6a..b48c06d 100644
--- a/skill/SKILL.md
+++ b/skill/SKILL.md
@@ -13,10 +13,13 @@ Use `mmx` to generate text, images, video, speech, music, and perform web search
 # Install
 npm install -g mmx-cli
 
-# Auth (persisted to ~/.mmx/credentials.json)
+# Auth — API key (persisted to ~/.mmx/config.json)
 mmx auth login --api-key sk-xxxxx
 
-# Or pass per-call
+# Auth — OAuth (persisted to ~/.mmx/credentials.json)
+mmx auth login
+
+# Or pass per-call (no file needed)
 mmx text chat --api-key sk-xxxxx --message "Hello"
 ```