diff --git a/src/llama-vocab.cpp b/src/llama-vocab.cpp
index bd311bea45..a20c6525e4 100644
--- a/src/llama-vocab.cpp
+++ b/src/llama-vocab.cpp
@@ -2203,6 +2203,8 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
         //       for now, we apply this workaround to find the tokens based on their text
 
         for (const auto & t : token_to_id) {
+            auto & attr = id_to_token[t.second].attr;
+
             // find EOT token: "<|eot_id|>", "<|im_end|>", "<end_of_turn>", etc.
             if (special_eot_id == LLAMA_TOKEN_NULL) {
                 if (false
@@ -2218,10 +2220,10 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
                         || t.first == "<end_of_utterance>" // smoldocling
                    ) {
                     special_eot_id = t.second;
-                    if ((id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                    if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
                         LLAMA_LOG_WARN("%s: control-looking token: %6d '%s' was not control-type; this is probably a bug in the model. its type will be overridden\n",
                                 __func__, t.second, t.first.c_str());
-                        id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_CONTROL;
+                        attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_CONTROL);
                     }
                 }
             }
@@ -2232,10 +2234,10 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
                         || t.first == "<|eom_id|>"
                         ) {
                     special_eom_id = t.second;
-                    if ((id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                    if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
                         LLAMA_LOG_WARN("%s: control-looking token: %6d '%s' was not control-type; this is probably a bug in the model. its type will be overridden\n",
                                 __func__, t.second, t.first.c_str());
-                        id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_CONTROL;
+                        attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_CONTROL);
                     }
                 }
             }
@@ -2252,10 +2254,10 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
                         || t.first == "<|code_prefix|>" // GLM-4.5
                         ) {
                     special_fim_pre_id = t.second;
-                    if ((id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                    if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
                         LLAMA_LOG_WARN("%s: control-looking token: %6d '%s' was not control-type; this is probably a bug in the model. its type will be overridden\n",
                                 __func__, t.second, t.first.c_str());
-                        id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_CONTROL;
+                        attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_CONTROL);
                     }
                 }
             }
@@ -2272,10 +2274,10 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
                         || t.first == "<|code_suffix|>" // GLM-4.5
                         ) {
                     special_fim_suf_id = t.second;
-                    if ((id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                    if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
                         LLAMA_LOG_WARN("%s: control-looking token: %6d '%s' was not control-type; this is probably a bug in the model. its type will be overridden\n",
                                 __func__, t.second, t.first.c_str());
-                        id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_CONTROL;
+                        attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_CONTROL);
                     }
                 }
             }
@@ -2292,10 +2294,10 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
                         || t.first == "<|code_middle|>" // GLM-4.5
                         ) {
                     special_fim_mid_id = t.second;
-                    if ((id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                    if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
                         LLAMA_LOG_WARN("%s: control-looking token: %6d '%s' was not control-type; this is probably a bug in the model. its type will be overridden\n",
                                 __func__, t.second, t.first.c_str());
-                        id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_CONTROL;
+                        attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_CONTROL);
                     }
                 }
             }
@@ -2309,10 +2311,10 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
                         || t.first == "<PAD>"
                         ) {
                     special_fim_pad_id = t.second;
-                    if ((id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                    if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
                         LLAMA_LOG_WARN("%s: control-looking token: %6d '%s' was not control-type; this is probably a bug in the model. its type will be overridden\n",
                                 __func__, t.second, t.first.c_str());
-                        id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_CONTROL;
+                        attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_CONTROL);
                     }
                 }
             }
@@ -2327,10 +2329,10 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
                         || t.first == "<reponame>"    // Granite
                         ) {
                     special_fim_rep_id = t.second;
-                    if ((id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                    if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
                         LLAMA_LOG_WARN("%s: control-looking token: %6d '%s' was not control-type; this is probably a bug in the model. its type will be overridden\n",
                                 __func__, t.second, t.first.c_str());
-                        id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_CONTROL;
+                        attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_CONTROL);
                     }
                 }
             }
@@ -2341,15 +2343,41 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
                         || t.first == "<|file_sep|>" // Qwen
                         ) {
                     special_fim_sep_id = t.second;
-                    if ((id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                    if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
                         LLAMA_LOG_WARN("%s: control-looking token: %6d '%s' was not control-type; this is probably a bug in the model. its type will be overridden\n",
                                 __func__, t.second, t.first.c_str());
-                        id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_CONTROL;
+                        attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_CONTROL);
                     }
                 }
             }
         }
 
+        // auto-detect unused tokens: e.g. control tokens with the word "unused"
+        // ideally, these tokens should be marked as unused during conversion
+        {
+            uint32_t n_unused = 0;
+
+            for (const auto & t : token_to_id) {
+                auto & attr = id_to_token[t.second].attr;
+
+                if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                    continue;
+                }
+
+                if ((attr & LLAMA_TOKEN_ATTR_UNUSED) == 0) {
+                    if (strstr(t.first.c_str(), "unused") != NULL) {
+                        attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_UNUSED);
+                    }
+                }
+
+                if (attr & LLAMA_TOKEN_ATTR_UNUSED) {
+                    n_unused++;
+                }
+            }
+
+            LLAMA_LOG_INFO("%s: %u unused tokens\n", __func__, n_unused);
+        }
+
         // maintain a list of tokens that cause end-of-generation
         // this is currently determined based on the token text, which is obviously not ideal
         // ref: https://github.com/ggerganov/llama.cpp/issues/9606
@@ -2368,6 +2396,8 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
         }
 
         for (const auto & t : token_to_id) {
+            auto & attr = id_to_token[t.second].attr;
+
             if (false
                     || t.first == "<|eot_id|>"
                     || t.first == "<|im_end|>"
@@ -2385,24 +2415,28 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
                     || t.first == "<end_of_utterance>" // smoldocling
                ) {
                 special_eog_ids.insert(t.second);
-                if ((id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
+                if ((attr & LLAMA_TOKEN_ATTR_CONTROL) == 0) {
                     LLAMA_LOG_WARN("%s: control-looking token: %6d '%s' was not control-type; this is probably a bug in the model. its type will be overridden\n",
                             __func__, t.second, t.first.c_str());
-                    id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_CONTROL;
+                    attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_CONTROL);
                 }
             } else {
-                // token is control, but not marked as EOG -> print a debug log
-                if (id_to_token[t.second].attr & LLAMA_TOKEN_ATTR_CONTROL && special_eog_ids.count(t.second) == 0) {
-                    LLAMA_LOG_DEBUG("%s: control token: %6d '%s' is not marked as EOG\n",
-                            __func__, t.second, t.first.c_str());
+                if (attr & LLAMA_TOKEN_ATTR_CONTROL && !(attr & LLAMA_TOKEN_ATTR_UNUSED)) {
+                    // token is control, but not marked as EOG -> print a debug log
+                    if (special_eog_ids.count(t.second) == 0) {
+                        LLAMA_LOG_DEBUG("%s: control token: %6d '%s' is not marked as EOG\n",
+                                __func__, t.second, t.first.c_str());
+                    }
                 }
             }
         }
 
         // @ngxson : quick hack for gpt-oss, always render these tokens
         for (const auto & t : token_to_id) {
+            auto & attr = id_to_token[t.second].attr;
+
             if (t.first == "<|channel|>" || t.first == "<|message|>" || t.first == "<|start|>" || t.first == "<|constrain|>") {
-                id_to_token[t.second].attr = LLAMA_TOKEN_ATTR_USER_DEFINED;
+                attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_USER_DEFINED);
             }
         }
 
@@ -2435,15 +2469,17 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
 
             LLAMA_LOG_INFO("%s: printing all EOG tokens:\n", __func__);
             for (auto tid : special_eog_ids) {
-                LLAMA_LOG_INFO("%s:   - %d ('%s')\n", __func__, tid, id_to_token[tid].text.c_str());
+                auto & text = id_to_token[tid].text;
 
-                if (id_to_token[tid].text == "<|return|>") {
+                LLAMA_LOG_INFO("%s:   - %d ('%s')\n", __func__, tid, text.c_str());
+
+                if (text == "<|return|>") {
                     has_return = true;
-                } else if (id_to_token[tid].text == "<|call|>" || id_to_token[tid].text == "<|calls|>") {
+                } else if (text == "<|call|>" || text == "<|calls|>") {
                     has_call = true;
-                } else if (id_to_token[tid].text == "<|flush|>") {
+                } else if (text == "<|flush|>") {
                     has_flush = true;
-                } else if (id_to_token[tid].text == "<|end|>") {
+                } else if (text == "<|end|>") {
                     has_end = true;
                     end_id = tid;
                 }
@@ -2451,7 +2487,10 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
 
             if ((has_return && has_call && has_end) || (has_call && has_flush && has_end)) {
                 special_eog_ids.erase(end_id);
-                id_to_token[end_id].attr = LLAMA_TOKEN_ATTR_USER_DEFINED;
+
+                auto & attr = id_to_token[end_id].attr;
+                attr = (llama_token_attr) (attr | LLAMA_TOKEN_ATTR_USER_DEFINED);
+
                 LLAMA_LOG_WARN("%s: special_eog_ids contains both '<|return|>' and '<|call|>', or '<|calls|>' and '<|flush|>' tokens, removing '<|end|>' token from EOG list\n", __func__);
             }
         }