diff --git a/server.py b/server.py
index 879e540..3e71f80 100644
--- a/server.py
+++ b/server.py
@@ -122,6 +122,13 @@ class GlobalConfig:
 
     EMAIL_HTML_SIGNATURE: str = ""
 
+    # LLM identity defaults (can be overridden per-call via signature_vars)
+    LLM_NAME: str = os.getenv("LLM_NAME", "")
+    LLM_TITLE: str = os.getenv("LLM_TITLE", "")
+    LLM_PHONE: str = os.getenv("LLM_PHONE", "")
+    LLM_ADDRESS: str = os.getenv("LLM_ADDRESS", "")
+    LLM_EMAIL: str = os.getenv("LLM_EMAIL", "")
+
     @classmethod
     def resolve_html_signature(cls, raw: str) -> str:
         if not raw:
@@ -136,6 +143,32 @@ class GlobalConfig:
         # Otherwise, treat as inline HTML
         return raw.strip()
 
+    @staticmethod
+    def render_signature_with_vars(signature_template: str, override_vars: Optional[Dict[str, str]] = None) -> str:
+        """
+        Replace {{NAME}}, {{TITLE}}, {{PHONE}}, {{ADDRESS}}, {{EMAIL}} in signature_template
+        using env-based defaults or per-call overrides.
+        """
+        if not signature_template:
+            return signature_template
+
+        if override_vars is None:
+            override_vars = {}
+
+        name = override_vars.get("NAME") or os.getenv("LLM_NAME", "")
+        title = override_vars.get("TITLE") or os.getenv("LLM_TITLE", "")
+        phone = override_vars.get("PHONE") or os.getenv("LLM_PHONE", "")
+        address = override_vars.get("ADDRESS") or os.getenv("LLM_ADDRESS", "")
+        email = override_vars.get("EMAIL") or os.getenv("LLM_EMAIL", "")
+
+        out = signature_template
+        out = out.replace("{{NAME}}", name)
+        out = out.replace("{{TITLE}}", title)
+        out = out.replace("{{PHONE}}", phone)
+        out = out.replace("{{ADDRESS}}", address)
+        out = out.replace("{{EMAIL}}", email)
+        return out
+
     @property
     def personnel(self) -> List[Dict[str, Any]]:
         try:
@@ -1097,9 +1130,20 @@ TOOLS = [
                 "body": {"type": "string"},
                 "cc": {"type": "array", "items": {"type": "string"}},
                 "bcc": {"type": "array", "items": {"type": "string"}},
-                "html": {"type": "boolean", "description": "Treat body as HTML"},
+                "html": {"type": "boolean", "description": "Treat body as HTML (default: true)"},
                 "in_reply_to": {"type": "string"},
-                "references": {"type": "string"}
+                "references": {"type": "string"},
+                "signature_vars": {
+                    "type": "object",
+                    "description": "Optional identity variables for signature template (NAME, TITLE, PHONE, ADDRESS, EMAIL)",
+                    "properties": {
+                        "NAME": {"type": "string"},
+                        "TITLE": {"type": "string"},
+                        "PHONE": {"type": "string"},
+                        "ADDRESS": {"type": "string"},
+                        "EMAIL": {"type": "string"}
+                    }
+                }
             },
             "required": ["to", "subject", "body"]
         }
@@ -1114,10 +1158,21 @@ TOOLS = [
                 "folder": {"type": "string"},
                 "uid": {"type": "integer"},
                 "body": {"type": "string"},
-                "html": {"type": "boolean"},
+                "html": {"type": "boolean", "description": "Treat body as HTML (default: true)"},
                 "to": {"type": "array", "items": {"type": "string"}, "description": "Override reply recipients"},
                 "cc": {"type": "array", "items": {"type": "string"}},
-                "bcc": {"type": "array", "items": {"type": "string"}}
+                "bcc": {"type": "array", "items": {"type": "string"}},
+                "signature_vars": {
+                    "type": "object",
+                    "description": "Optional identity variables for signature template (NAME, TITLE, PHONE, ADDRESS, EMAIL)",
+                    "properties": {
+                        "NAME": {"type": "string"},
+                        "TITLE": {"type": "string"},
+                        "PHONE": {"type": "string"},
+                        "ADDRESS": {"type": "string"},
+                        "EMAIL": {"type": "string"}
+                    }
+                }
             },
             "required": ["folder", "uid", "body"]
         }
@@ -1135,7 +1190,18 @@ TOOLS = [
                 "cc": {"type": "array", "items": {"type": "string"}},
                 "bcc": {"type": "array", "items": {"type": "string"}},
                 "note": {"type": "string", "description": "Optional note to prepend"},
-                "html": {"type": "boolean"}
+                "html": {"type": "boolean", "description": "Treat body as HTML (default: true)"},
+                "signature_vars": {
+                    "type": "object",
+                    "description": "Optional identity variables for signature template (NAME, TITLE, PHONE, ADDRESS, EMAIL)",
+                    "properties": {
+                        "NAME": {"type": "string"},
+                        "TITLE": {"type": "string"},
+                        "PHONE": {"type": "string"},
+                        "ADDRESS": {"type": "string"},
+                        "EMAIL": {"type": "string"}
+                    }
+                }
             },
             "required": ["folder", "uid", "to"]
         }
@@ -1209,10 +1275,21 @@ TOOLS = [
                 "body": {"type": "string"},
                 "cc": {"type": "array", "items": {"type": "string"}},
                 "bcc": {"type": "array", "items": {"type": "string"}},
-                "html": {"type": "boolean"},
+                "html": {"type": "boolean", "description": "Treat body as HTML (default: true)"},
                 "send_at": {"type": "number", "description": "Unix timestamp when to send"},
                 "in_reply_to": {"type": "string"},
-                "references": {"type": "string"}
+                "references": {"type": "string"},
+                "signature_vars": {
+                    "type": "object",
+                    "description": "Optional identity variables for signature template (NAME, TITLE, PHONE, ADDRESS, EMAIL)",
+                    "properties": {
+                        "NAME": {"type": "string"},
+                        "TITLE": {"type": "string"},
+                        "PHONE": {"type": "string"},
+                        "ADDRESS": {"type": "string"},
+                        "EMAIL": {"type": "string"}
+                    }
+                }
             },
             "required": ["to", "subject", "body", "send_at"]
         }
@@ -1631,8 +1708,13 @@ def send_email_impl(args):
         html = True
 
     body = args["body"]
+
+    # Use LLM-provided identity if present
+    signature_vars = args.get("signature_vars") or {}
+
     if html and config.EMAIL_HTML_SIGNATURE:
-        body = body.rstrip("\n") + "\n" + config.EMAIL_HTML_SIGNATURE
+        sig = GlobalConfig.render_signature_with_vars(config.EMAIL_HTML_SIGNATURE, signature_vars)
+        body = body.rstrip("\n") + "\n" + sig
 
     try:
         send_email(
@@ -1660,8 +1742,13 @@ def schedule_send_impl(args):
         html = True
 
     body = args["body"]
+
+    # Use LLM-provided identity if present
+    signature_vars = args.get("signature_vars") or {}
+
     if html and config.EMAIL_HTML_SIGNATURE:
-        body = body.rstrip("\n") + "\n" + config.EMAIL_HTML_SIGNATURE
+        sig = GlobalConfig.render_signature_with_vars(config.EMAIL_HTML_SIGNATURE, signature_vars)
+        body = body.rstrip("\n") + "\n" + sig
 
     task_id = add_scheduled_send(
         account_id=account_id,
@@ -1678,7 +1765,7 @@ def schedule_send_impl(args):
     return {"status": "scheduled", "task_id": task_id, "account": account_id}
 
 
-def reply_to_message_impl(account=None, folder=None, uid=None, body=None, html=None, to=None, cc=None, bcc=None):
+def reply_to_message_impl(account=None, folder=None, uid=None, body=None, html=None, to=None, cc=None, bcc=None, signature_vars=None):
     acc = get_account(account)
     imap = create_imap(acc)
     try:
@@ -1712,7 +1799,8 @@ def reply_to_message_impl(account=None, folder=None, uid=None, body=None, html=N
 
         # Append HTML signature if sending as HTML
         if html and config.EMAIL_HTML_SIGNATURE:
-            body = (body or "").rstrip("\n") + "\n" + config.EMAIL_HTML_SIGNATURE
+            sig = GlobalConfig.render_signature_with_vars(config.EMAIL_HTML_SIGNATURE, signature_vars or {})
+            body = (body or "").rstrip("\n") + "\n" + sig
 
         send_email(
             acc=acc,
@@ -1730,7 +1818,7 @@ def reply_to_message_impl(account=None, folder=None, uid=None, body=None, html=N
         imap.logout()
 
 
-def forward_message_impl(account=None, folder=None, uid=None, to=None, cc=None, bcc=None, note="", html=None, body=None):
+def forward_message_impl(account=None, folder=None, uid=None, to=None, cc=None, bcc=None, note="", html=None, body=None, signature_vars=None):
     acc = get_account(account)
     imap = create_imap(acc)
     try:
@@ -1756,7 +1844,8 @@ def forward_message_impl(account=None, folder=None, uid=None, to=None, cc=None,
 
         # Append HTML signature if sending as HTML
         if html and config.EMAIL_HTML_SIGNATURE:
-            body = body.rstrip("\n") + "\n" + config.EMAIL_HTML_SIGNATURE
+            sig = GlobalConfig.render_signature_with_vars(config.EMAIL_HTML_SIGNATURE, signature_vars or {})
+            body = body.rstrip("\n") + "\n" + sig
 
         send_email(
             acc=acc,