diff --git a/API.md b/API.md
index 1c0d7db..90650e5 100644
--- a/API.md
+++ b/API.md
@@ -292,7 +292,7 @@ The store is exposed as a `LibDashStore` instance (see `src/index.js`). Each met
   - `list(googleAuthId: number, tx?: object): Promise<Array<{id: number, companyuser_id: number, provider: string, model: string, created_at: string, updated_at: string, state: string}>>`
   - `setState(googleAuthId: number, conversationId: number, state: string, tx?: object): Promise<{id: number, companyuser_id: number, provider: string, model: string, created_at: string, updated_at: string, state: string}>`
 - [modelmessage](API.modelmessage.md)
-  - `add(googleAuthId: number, conversationId: number, input: {message: string, role?: 'user'|'assistant'|'system'|'tool'|'reasoning'}, tx?: object): Promise<{id: number, conversation_id: number, created_at: string, role: string, message: string}>`
+  - `add(googleAuthId: number, conversationId: number, input: {message: string, role?: 'user'|'assistant'|'system'|'tool'|'reasoning'|'usage'}, tx?: object): Promise<{id: number, conversation_id: number, created_at: string, role: string, message: string}>`
   - `list(googleAuthId: number, conversationId: number, tx?: object): Promise<Array<{id: number, conversation_id: number, created_at: string, role: string, message: string}>>`
 - [modelvfs](API.modelvfs.md)
   - `delete(googleAuthId: number, name: string, tx?: object): Promise<{deleted: boolean}>`
diff --git a/API.modelmessage.md b/API.modelmessage.md
index 7e15e94..54f03b0 100644
--- a/API.modelmessage.md
+++ b/API.modelmessage.md
@@ -16,7 +16,7 @@ Appends a message to one of the user's own conversations. `user` messages are re
 | `conversationId` | `number` | The conversation id. |
 | `input` | `object` | Message input. |
 | `input.message` | `string` | Message text. |
-| `[input.role='user']` | `'user'|'assistant'|'system'|'tool'|'reasoning'` | Message role. |
+| `[input.role='user']` | `'user'|'assistant'|'system'|'tool'|'reasoning'|'usage'` | Message role. |
 | `[tx]` | `object` | Optional transaction to run within. |
 
 **Returns**
diff --git a/src/providers/mssql/schema.js b/src/providers/mssql/schema.js
index 66385ed..feed3cc 100644
--- a/src/providers/mssql/schema.js
+++ b/src/providers/mssql/schema.js
@@ -833,7 +833,7 @@ BEGIN
         role NVARCHAR(20) NOT NULL,
         message NVARCHAR(MAX) NOT NULL,
         CONSTRAINT FK_modelmessage_conversation FOREIGN KEY (conversation_id) REFERENCES modelconversation(id) ON DELETE CASCADE,
-        CONSTRAINT CK_modelmessage_role CHECK (role IN ('system', 'user', 'assistant', 'tool', 'reasoning'))
+        CONSTRAINT CK_modelmessage_role CHECK (role IN ('system', 'user', 'assistant', 'tool', 'reasoning', 'usage'))
     );
     CREATE INDEX IX_modelmessage_conversation ON modelmessage (conversation_id, id);
 END
diff --git a/src/providers/sqlite3/schema.js b/src/providers/sqlite3/schema.js
index 8f40670..10251e1 100644
--- a/src/providers/sqlite3/schema.js
+++ b/src/providers/sqlite3/schema.js
@@ -518,7 +518,7 @@ CREATE TABLE IF NOT EXISTS modelmessage (
     id INTEGER PRIMARY KEY,
     conversation_id INTEGER NOT NULL,
     created_at TEXT NOT NULL DEFAULT (${UTC_NOW}),
-    role TEXT NOT NULL CHECK (role IN ('system', 'user', 'assistant', 'tool', 'reasoning')),
+    role TEXT NOT NULL CHECK (role IN ('system', 'user', 'assistant', 'tool', 'reasoning', 'usage')),
     message TEXT NOT NULL,
     FOREIGN KEY (conversation_id) REFERENCES modelconversation(id) ON DELETE CASCADE
 );
diff --git a/src/store/modelmessage/add.js b/src/store/modelmessage/add.js
index 670cc79..ced1826 100644
--- a/src/store/modelmessage/add.js
+++ b/src/store/modelmessage/add.js
@@ -31,7 +31,7 @@ export default function add(provider) {
    * @param {number} conversationId - The conversation id.
    * @param {object} input - Message input.
    * @param {string} input.message - Message text.
-   * @param {'user'|'assistant'|'system'|'tool'|'reasoning'} [input.role='user'] - Message role.
+   * @param {'user'|'assistant'|'system'|'tool'|'reasoning'|'usage'} [input.role='user'] - Message role.
    * @param {object} [tx] - Optional transaction to run within.
    * @returns {Promise<{id: number, conversation_id: number, created_at: string, role: string, message: string}>}
    * @throws {Error} 'Conversation not found', 'Conversation is not idle', 'Message required', 'Invalid role'.
@@ -42,7 +42,7 @@ export default function add(provider) {
       throw new Error('Conversation not found');
     }
     const role = input.role || 'user';
-    if (!['user', 'assistant', 'system', 'tool', 'reasoning'].includes(role)) {
+    if (!['user', 'assistant', 'system', 'tool', 'reasoning', 'usage'].includes(role)) {
       throw new Error('Invalid role');
     }
     const message = input.message != null ? String(input.message) : '';