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+
+> For the demo, language ∈ {EN_JA, EN_ZH-CN}
+
+POST /ai-mark {
+	question: str, 
+	user_answer: str, 
+	expected: str, 
+	chapter: str,
+	language: str
+}
+-> {correct: bool, reason: str}
+
+POST /human-chat {
+	target_name: str,
+	target_hobbies: list\[str],
+	history: list\[{from\_me: bool, msg: str}],
+	language: str
+}
+-> {msg: str}
+
+> Chat histories will be stored in localStorage
+
+POST /recognize (Body is an audio file)
+-> {text: str}
+
+POST /character-chat {
+	character: str
+	history: list\[{from_me: bool, msg: str}]
+	language: str
+}
+-> {msg: str, audio: UUID}
+
+GET /audio/{UUID}
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