diff --git a/agent/auxiliary_client.py b/agent/auxiliary_client.py
index b8229bb5e..0ad4de220 100644
--- a/agent/auxiliary_client.py
+++ b/agent/auxiliary_client.py
@@ -35,6 +35,14 @@ _OR_HEADERS = {
     "X-OpenRouter-Categories": "cli-agent",
 }
 
+# Nous Portal extra_body for product attribution.
+# Callers should pass this as extra_body in chat.completions.create()
+# when the auxiliary client is backed by Nous Portal.
+NOUS_EXTRA_BODY = {"tags": ["product=hermes-agent"]}
+
+# Set at resolve time — True if the auxiliary client points to Nous Portal
+auxiliary_is_nous: bool = False
+
 # Default auxiliary models per provider
 _OPENROUTER_MODEL = "google/gemini-3-flash-preview"
 _NOUS_MODEL = "gemini-3-flash"
@@ -91,6 +99,8 @@ def get_text_auxiliary_client() -> Tuple[Optional[OpenAI], Optional[str]]:
     # 2. Nous Portal
     nous = _read_nous_auth()
     if nous:
+        global auxiliary_is_nous
+        auxiliary_is_nous = True
         logger.debug("Auxiliary text client: Nous Portal")
         return (
             OpenAI(api_key=_nous_api_key(nous), base_url=_nous_base_url()),
@@ -135,3 +145,12 @@ def get_vision_auxiliary_client() -> Tuple[Optional[OpenAI], Optional[str]]:
     # 3. Nothing suitable
     logger.debug("Auxiliary vision client: none available")
     return None, None
+
+
+def get_auxiliary_extra_body() -> dict:
+    """Return extra_body kwargs for auxiliary API calls.
+    
+    Includes Nous Portal product tags when the auxiliary client is backed
+    by Nous Portal. Returns empty dict otherwise.
+    """
+    return dict(NOUS_EXTRA_BODY) if auxiliary_is_nous else {}
diff --git a/tools/openrouter_client.py b/tools/openrouter_client.py
index c960f4f4a..7d30e6eec 100644
--- a/tools/openrouter_client.py
+++ b/tools/openrouter_client.py
@@ -25,7 +25,15 @@ def get_async_client() -> AsyncOpenAI:
         api_key = os.getenv("OPENROUTER_API_KEY")
         if not api_key:
             raise ValueError("OPENROUTER_API_KEY environment variable not set")
-        _client = AsyncOpenAI(api_key=api_key, base_url=OPENROUTER_BASE_URL)
+        _client = AsyncOpenAI(
+            api_key=api_key,
+            base_url=OPENROUTER_BASE_URL,
+            default_headers={
+                "HTTP-Referer": "https://github.com/NousResearch/hermes-agent",
+                "X-OpenRouter-Title": "Hermes Agent",
+                "X-OpenRouter-Categories": "cli-agent",
+            },
+        )
     return _client
 
 
diff --git a/tools/session_search_tool.py b/tools/session_search_tool.py
index 179d485c0..299286d98 100644
--- a/tools/session_search_tool.py
+++ b/tools/session_search_tool.py
@@ -170,12 +170,15 @@ async def _summarize_session(
     max_retries = 3
     for attempt in range(max_retries):
         try:
+            from agent.auxiliary_client import get_auxiliary_extra_body
+            _extra = get_auxiliary_extra_body()
             response = await _async_aux_client.chat.completions.create(
                 model=_SUMMARIZER_MODEL,
                 messages=[
                     {"role": "system", "content": system_prompt},
                     {"role": "user", "content": user_prompt},
                 ],
+                **({} if not _extra else {"extra_body": _extra}),
                 temperature=0.1,
                 max_tokens=MAX_SUMMARY_TOKENS,
             )
diff --git a/tools/vision_tools.py b/tools/vision_tools.py
index 4b88724ab..456f85583 100644
--- a/tools/vision_tools.py
+++ b/tools/vision_tools.py
@@ -314,11 +314,14 @@ async def vision_analyze_tool(
         logger.info("Processing image with %s...", model)
         
         # Call the vision API
+        from agent.auxiliary_client import get_auxiliary_extra_body
+        _extra = get_auxiliary_extra_body()
         response = await _aux_async_client.chat.completions.create(
             model=model,
             messages=messages,
             temperature=0.1,
             max_tokens=2000,
+            **({} if not _extra else {"extra_body": _extra}),
         )
         
         # Extract the analysis
diff --git a/tools/web_tools.py b/tools/web_tools.py
index 8610e38c6..a7f64166e 100644
--- a/tools/web_tools.py
+++ b/tools/web_tools.py
@@ -242,6 +242,8 @@ Create a markdown summary that captures all key information in a well-organized,
             if _aux_async_client is None:
                 logger.warning("No auxiliary model available for web content processing")
                 return None
+            from agent.auxiliary_client import get_auxiliary_extra_body
+            _extra = get_auxiliary_extra_body()
             response = await _aux_async_client.chat.completions.create(
                 model=model,
                 messages=[
@@ -250,6 +252,7 @@ Create a markdown summary that captures all key information in a well-organized,
                 ],
                 temperature=0.1,
                 max_tokens=max_tokens,
+                **({} if not _extra else {"extra_body": _extra}),
             )
             return response.choices[0].message.content.strip()
         except Exception as api_error:
@@ -362,6 +365,8 @@ Create a single, unified markdown summary."""
                 fallback = fallback[:max_output_size] + "\n\n[... truncated ...]"
             return fallback
 
+        from agent.auxiliary_client import get_auxiliary_extra_body
+        _extra = get_auxiliary_extra_body()
         response = await _aux_async_client.chat.completions.create(
             model=model,
             messages=[
@@ -370,6 +375,7 @@ Create a single, unified markdown summary."""
             ],
             temperature=0.1,
             max_tokens=4000,
+            **({} if not _extra else {"extra_body": _extra}),
         )
         final_summary = response.choices[0].message.content.strip()