diff --git a/python/sglang/srt/managers/schedule_batch.py b/python/sglang/srt/managers/schedule_batch.py
index 51167bc60..9d9e09e66 100755
--- a/python/sglang/srt/managers/schedule_batch.py
+++ b/python/sglang/srt/managers/schedule_batch.py
@@ -1445,7 +1445,7 @@ class Req(ReqDllmMixin):
         kv, self.kv = self.kv, ReqKvInfo()
         return kv
 
-    def effective_kv_committed_len(self) -> int:
+    def owned_kv_len(self) -> int:
         # Report only the prompt prefix so thinking + answer fall into the
         # overallocated range and are reclaimed by release_kv_cache. #22373.
         if get_serving().strip_thinking_cache and self.reasoning_tokens > 0:
diff --git a/python/sglang/srt/mem_cache/base_prefix_cache.py b/python/sglang/srt/mem_cache/base_prefix_cache.py
index 5d260f241..81a1a5d95 100644
--- a/python/sglang/srt/mem_cache/base_prefix_cache.py
+++ b/python/sglang/srt/mem_cache/base_prefix_cache.py
@@ -434,8 +434,18 @@ class BasePrefixCache(ABC, PrefixCacheTrait):
         return None
 
     @abstractmethod
-    def cache_finished_req(self, req: Req, is_insert: bool = True, **kwargs):
-        pass
+    def cache_finished_req(
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int, **kwargs
+    ):
+        """Dispose of a finished request's KV.
+
+        ``[0, req.kv.cache_protected_len)`` is cache-owned and must survive.
+        Every slot in ``[req.kv.cache_protected_len, owned_kv_len)`` is this
+        call's to account for: insert what can be keyed, release the rest.
+        Slicing the kv row by the token-id count instead strands whatever
+        lies between -- no caller releases those. ``release_kv_cache`` frees
+        everything past ``owned_kv_len``.
+        """
 
     @abstractmethod
     def cache_unfinished_req(self, req: Req, **kwargs):
diff --git a/python/sglang/srt/mem_cache/cache_init_params.py b/python/sglang/srt/mem_cache/cache_init_params.py
index 75c54a074..fbfca879a 100644
--- a/python/sglang/srt/mem_cache/cache_init_params.py
+++ b/python/sglang/srt/mem_cache/cache_init_params.py
@@ -30,7 +30,6 @@ class CacheInitParams:
     # Keyword arguments for the eviction policy's constructor; see the strategy
     # classes in evict_policy.py for what each policy accepts.
     eviction_policy_config: Optional[dict[str, Any]] = None
-    disable_finished_insert: bool = False
 
     enable_metrics: bool = False
     enable_kv_cache_events: bool = False
diff --git a/python/sglang/srt/mem_cache/chunk_cache.py b/python/sglang/srt/mem_cache/chunk_cache.py
index ab3bc4afb..8c005ac39 100644
--- a/python/sglang/srt/mem_cache/chunk_cache.py
+++ b/python/sglang/srt/mem_cache/chunk_cache.py
@@ -77,11 +77,11 @@ class ChunkCache(BasePrefixCache):
         return InsertResult(prefix_len=0)
 
     def cache_finished_req(
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int
     ):
         # For decode server: if req.output_ids is empty, we want to free all req.origin_input_ids
         # The protected prefix is not this req's to free.
-        self.free_kv_row(req.kv, [(req.kv.cache_protected_len, kv_len_to_handle)])
+        self.free_kv_row(req.kv, [(req.kv.cache_protected_len, owned_kv_len)])
 
     def cache_unfinished_req(self, req: Req, chunked=False):
         kv_indices = self.req_to_token_pool.req_to_token[
@@ -151,11 +151,10 @@ class PureSWAChunkCache(SWAChunkCache):
     """
 
     def cache_finished_req(
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int
     ):
-        kv_committed_len = kv_len_to_handle
         kv_indices = self.req_to_token_pool.req_to_token[
-            req.kv.req_pool_idx, :kv_committed_len
+            req.kv.req_pool_idx, :owned_kv_len
         ]
         # The cache_protected_len prefix is not this req's to free.
         protected_len = req.kv.cache_protected_len
@@ -165,9 +164,9 @@ class PureSWAChunkCache(SWAChunkCache):
             parts = []
             if evict_floor > protected_len:
                 parts.append(kv_indices[protected_len:evict_floor])
-            if evicted_seqlen < kv_committed_len:
+            if evicted_seqlen < owned_kv_len:
                 parts.append(
-                    kv_indices[max(evicted_seqlen, protected_len) : kv_committed_len]
+                    kv_indices[max(evicted_seqlen, protected_len) : owned_kv_len]
                 )
             if parts:
                 self.token_to_kv_pool_allocator.free(torch.cat(parts))
diff --git a/python/sglang/srt/mem_cache/common.py b/python/sglang/srt/mem_cache/common.py
index 22dd0729a..fda235acf 100644
--- a/python/sglang/srt/mem_cache/common.py
+++ b/python/sglang/srt/mem_cache/common.py
@@ -284,11 +284,11 @@ def release_kv_cache(req: Req, tree_cache: BasePrefixCache, is_insert: bool = Tr
             req.kv.mamba_pool_idx = None
         return
 
-    effective_kv_committed_len = req.effective_kv_committed_len()
+    owned_kv_len = req.owned_kv_len()
     tree_cache.cache_finished_req(
         req,
         is_insert=is_insert and not getattr(req, "skip_radix_cache_insert", False),
-        kv_len_to_handle=effective_kv_committed_len,
+        owned_kv_len=owned_kv_len,
     )
 
     # StreamingSession.cache_finished_req handles speculative tail trim
@@ -297,7 +297,7 @@ def release_kv_cache(req: Req, tree_cache: BasePrefixCache, is_insert: bool = Tr
     if not req.kv.holds_kv:
         return
 
-    start_p, end_p = effective_kv_committed_len, req.kv.kv_allocated_len
+    start_p, end_p = owned_kv_len, req.kv.kv_allocated_len
     _release_overallocated_kv_indices(req, start_p, end_p, tree_cache)
 
     # If the prefix cache doesn't manage mamba states, we must free them here.
diff --git a/python/sglang/srt/mem_cache/mamba_radix_cache.py b/python/sglang/srt/mem_cache/mamba_radix_cache.py
index e98bdec52..e2faa6efe 100644
--- a/python/sglang/srt/mem_cache/mamba_radix_cache.py
+++ b/python/sglang/srt/mem_cache/mamba_radix_cache.py
@@ -544,20 +544,20 @@ class MambaRadixCache(BasePrefixCache):
         return InsertResult(prefix_len=prefix_len, mamba_exist=mamba_exist)
 
     def cache_finished_req(
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int
     ) -> None:
         """Cache request when it finishes."""
         if self.disable:
             kv_indices = self.req_to_token_pool.req_to_token[
-                req.kv.req_pool_idx, :kv_len_to_handle
+                req.kv.req_pool_idx, :owned_kv_len
             ]
             self.token_to_kv_pool_allocator.free_segment(kv_indices, start_pos=0)
             self.req_to_token_pool.free_mamba_cache(req)
             return
 
-        token_ids = (req.origin_input_ids + req.output_ids)[:kv_len_to_handle]
+        token_ids = (req.origin_input_ids + req.output_ids)[:owned_kv_len]
         kv_indices = self.req_to_token_pool.req_to_token[
-            req.kv.req_pool_idx, :kv_len_to_handle
+            req.kv.req_pool_idx, :owned_kv_len
         ]
 
         if is_insert:
@@ -607,7 +607,7 @@ class MambaRadixCache(BasePrefixCache):
                 page_aligned_kv_indices = kv_indices.to(dtype=torch.int64, copy=True)
 
             assert cache_len == page_aligned_len, (
-                f"It is required {cache_len=}, {page_aligned_len=}, {kv_len_to_handle=}, {len(req.origin_input_ids)=}, {len(req.output_ids)=} ping @yizhang2077 if you see this"
+                f"It is required {cache_len=}, {page_aligned_len=}, {owned_kv_len=}, {len(req.origin_input_ids)=}, {len(req.output_ids)=} ping @yizhang2077 if you see this"
             )
 
             # Radix Cache takes one ref in memory pool
diff --git a/python/sglang/srt/mem_cache/pure_swa_radix_cache.py b/python/sglang/srt/mem_cache/pure_swa_radix_cache.py
index 0636d0c13..2a652fc31 100644
--- a/python/sglang/srt/mem_cache/pure_swa_radix_cache.py
+++ b/python/sglang/srt/mem_cache/pure_swa_radix_cache.py
@@ -63,7 +63,7 @@ class PureSWARadixCache(RadixCache):
         return super().evict(EvictParams(num_tokens=num_tokens))
 
     def cache_finished_req(
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int
     ):
         """Cache request when it finishes.
 
@@ -72,20 +72,16 @@ class PureSWARadixCache(RadixCache):
         to the allocator. The range [evict_floor, swa_evicted_seqlen) was already
         freed by _evict_swa during decode — we skip it to avoid double-free.
         """
-        if self.disable_finished_insert:
-            is_insert = False
-
-        kv_committed_len = kv_len_to_handle
         if self.disable:
             kv_indices = self.req_to_token_pool.req_to_token[
-                req.kv.req_pool_idx, :kv_committed_len
+                req.kv.req_pool_idx, :owned_kv_len
             ]
             self.token_to_kv_pool_allocator.free(kv_indices)
             return
 
-        token_ids = (req.origin_input_ids + req.output_ids)[:kv_committed_len]
+        token_ids = (req.origin_input_ids + req.output_ids)[:owned_kv_len]
         kv_indices = self.req_to_token_pool.req_to_token[
-            req.kv.req_pool_idx, :kv_committed_len
+            req.kv.req_pool_idx, :owned_kv_len
         ]
 
         radix_key = RadixKey(
diff --git a/python/sglang/srt/mem_cache/radix_cache.py b/python/sglang/srt/mem_cache/radix_cache.py
index 05c31b6c3..3eaebc5e9 100644
--- a/python/sglang/srt/mem_cache/radix_cache.py
+++ b/python/sglang/srt/mem_cache/radix_cache.py
@@ -325,7 +325,6 @@ class RadixCache(BasePrefixCache):
         self.token_to_kv_pool_allocator = params.token_to_kv_pool_allocator
         self.page_size = params.page_size
         self.is_eagle = params.is_eagle
-        self.disable_finished_insert = params.disable_finished_insert
         self.eviction_policy = params.eviction_policy.lower()
 
         self.kv_events = KVCacheEventRecorder(
@@ -477,17 +476,13 @@ class RadixCache(BasePrefixCache):
         return InsertResult(prefix_len=prefix_len, last_device_node=last_node)
 
     def cache_finished_req(
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int
     ):
         """Cache request when it finishes."""
-        # In deterministic mode, disable finished request insertion to radix cache
-        if self.disable_finished_insert:
-            is_insert = False
-
         if self.disable:
             # The protected prefix is not this req's to free.
             kv_indices = self.req_to_token_pool.req_to_token[
-                req.kv.req_pool_idx, req.kv.cache_protected_len : kv_len_to_handle
+                req.kv.req_pool_idx, req.kv.cache_protected_len : owned_kv_len
             ]
             self.token_to_kv_pool_allocator.free_segment(
                 kv_indices, start_pos=req.kv.cache_protected_len
@@ -498,7 +493,7 @@ class RadixCache(BasePrefixCache):
             # Frees committed slots that no token id names, which the insert
             # path below cannot reach; the protected prefix stays with the cache.
             kv_indices = self.req_to_token_pool.req_to_token[
-                req.kv.req_pool_idx, req.kv.cache_protected_len : kv_len_to_handle
+                req.kv.req_pool_idx, req.kv.cache_protected_len : owned_kv_len
             ]
             self.token_to_kv_pool_allocator.free_segment(
                 kv_indices, start_pos=req.kv.cache_protected_len
@@ -507,9 +502,9 @@ class RadixCache(BasePrefixCache):
                 self.dec_lock_ref(req.last_node)
             return
 
-        token_ids = (req.origin_input_ids + req.output_ids)[:kv_len_to_handle]
+        token_ids = (req.origin_input_ids + req.output_ids)[:owned_kv_len]
         kv_indices = self.req_to_token_pool.req_to_token[
-            req.kv.req_pool_idx, : len(token_ids)
+            req.kv.req_pool_idx, :owned_kv_len
         ]
 
         radix_key = RadixKey(
diff --git a/python/sglang/srt/mem_cache/radix_cache_cpp.py b/python/sglang/srt/mem_cache/radix_cache_cpp.py
index d1dc22ba5..168df6eb1 100644
--- a/python/sglang/srt/mem_cache/radix_cache_cpp.py
+++ b/python/sglang/srt/mem_cache/radix_cache_cpp.py
@@ -181,20 +181,20 @@ class RadixCacheCpp(BasePrefixCache):
         return self.tree.total_size()
 
     def cache_finished_req(
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int
     ):
         """Cache request when it finishes."""
         self._reject_cache_salt(req.cache_salt)
         assert req.kv.holds_kv
-        token_ids = (req.origin_input_ids + req.output_ids)[:kv_len_to_handle]
+        token_ids = (req.origin_input_ids + req.output_ids)[:owned_kv_len]
         kv_indices = self.req_to_token_pool.req_to_token[
-            req.kv.req_pool_idx, :kv_len_to_handle
+            req.kv.req_pool_idx, :owned_kv_len
         ].to(dtype=torch.int64, copy=True)
 
         # NOTE: our C++ implementation don't need `token_ids` and `kv_indices` to be page-aligned
         # it will automatically align them, but length of them should be equal
         old_prefix_len = len(req.prefix_indices) // self.page_size * self.page_size
-        page_aligned_overall_len = kv_len_to_handle // self.page_size * self.page_size
+        page_aligned_overall_len = owned_kv_len // self.page_size * self.page_size
 
         if is_insert:
             new_prefix_len = self._insert(
@@ -213,7 +213,7 @@ class RadixCacheCpp(BasePrefixCache):
             )
 
         # need to free the unaligned part, since it cannot be inserted into the radix tree
-        if page_aligned_overall_len < kv_len_to_handle:
+        if page_aligned_overall_len < owned_kv_len:
             # NOTE: sglang PagedAllocator support unaligned free (which will automatically align it)
             self.token_to_kv_pool_allocator.free(kv_indices[page_aligned_overall_len:])
 
diff --git a/python/sglang/srt/mem_cache/storage/flexkv/flexkv_radix_cache.py b/python/sglang/srt/mem_cache/storage/flexkv/flexkv_radix_cache.py
index deba6a699..0a14cd84a 100644
--- a/python/sglang/srt/mem_cache/storage/flexkv/flexkv_radix_cache.py
+++ b/python/sglang/srt/mem_cache/storage/flexkv/flexkv_radix_cache.py
@@ -386,12 +386,10 @@ class FlexKVRadixCache(RadixCache):
     # ------------------------------------------------------------------
 
     def cache_finished_req(  # type: ignore[override]
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int
     ) -> None:
         """Base cache_finished_req then fire an async FlexKV store."""
-        super().cache_finished_req(
-            req, is_insert=is_insert, kv_len_to_handle=kv_len_to_handle
-        )
+        super().cache_finished_req(req, is_insert=is_insert, owned_kv_len=owned_kv_len)
         if not is_insert:
             self._load_markers.pop(req.cache_request_handle, None)
             return
diff --git a/python/sglang/srt/mem_cache/storage/lmcache/lmc_radix_cache.py b/python/sglang/srt/mem_cache/storage/lmcache/lmc_radix_cache.py
index e07754690..fdb019bb4 100644
--- a/python/sglang/srt/mem_cache/storage/lmcache/lmc_radix_cache.py
+++ b/python/sglang/srt/mem_cache/storage/lmcache/lmc_radix_cache.py
@@ -439,13 +439,11 @@ class LMCRadixCache(RadixCache):
             )
 
     def cache_finished_req(
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int
     ) -> None:
         """On request completion, insert device KV into radix and store to LMCache."""
 
-        super().cache_finished_req(
-            req, is_insert=is_insert, kv_len_to_handle=kv_len_to_handle
-        )
+        super().cache_finished_req(req, is_insert=is_insert, owned_kv_len=owned_kv_len)
         if not is_insert:
             if self._mode is LMCacheMode.MP:
                 self._mp_load_back_markers.pop(req.rid, None)
diff --git a/python/sglang/srt/mem_cache/swa_radix_cache.py b/python/sglang/srt/mem_cache/swa_radix_cache.py
index dbc6d8b91..ffce936f0 100644
--- a/python/sglang/srt/mem_cache/swa_radix_cache.py
+++ b/python/sglang/srt/mem_cache/swa_radix_cache.py
@@ -460,16 +460,16 @@ class SWARadixCache(BasePrefixCache):
         return InsertResult(prefix_len=prefix_len)
 
     def cache_finished_req(
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int
     ) -> None:
         """Cache request when it finishes."""
         if self.disable:
-            self.free_kv_row(req.kv, [(0, kv_len_to_handle)])
+            self.free_kv_row(req.kv, [(0, owned_kv_len)])
             return
 
-        token_ids = (req.origin_input_ids + req.output_ids)[:kv_len_to_handle]
+        token_ids = (req.origin_input_ids + req.output_ids)[:owned_kv_len]
         kv_indices = self.req_to_token_pool.req_to_token[
-            req.kv.req_pool_idx, :kv_len_to_handle
+            req.kv.req_pool_idx, :owned_kv_len
         ]
 
         radix_key = RadixKey(
@@ -497,7 +497,7 @@ class SWARadixCache(BasePrefixCache):
             self.free_kv_row(req.kv, [(old_prefix_len, page_aligned_len)])
 
         # free the unaligned tail
-        self.free_kv_row(req.kv, [(page_aligned_len, kv_len_to_handle)])
+        self.free_kv_row(req.kv, [(page_aligned_len, owned_kv_len)])
 
         # Remove req slot release the cache lock
         self.dec_lock_ref(
diff --git a/python/sglang/srt/mem_cache/unified_cache/components/README.md b/python/sglang/srt/mem_cache/unified_cache/components/README.md
index f0b1c61b6..c5d0e5cf1 100644
--- a/python/sglang/srt/mem_cache/unified_cache/components/README.md
+++ b/python/sglang/srt/mem_cache/unified_cache/components/README.md
@@ -228,14 +228,14 @@ receipt proves were taken. The eventual full release must pass
 
 ---
 
-### `cache_finished_req(req: Req, is_insert: bool = True, *, kv_len_to_handle: int)`
+### `cache_finished_req(req: Req, is_insert: bool = True, *, owned_kv_len: int)`
 
 Cache a completed request's KV data into the tree.
 
 | Aspect | Detail |
 |--------|--------|
 | **Purpose** | After a request finishes, insert its token/KV data into the tree for future reuse |
-| **Inputs** | `req` — the finished request; `is_insert` — whether to insert (True) or just release locks (False); `kv_len_to_handle` — committed KV length supplied by the caller |
+| **Inputs** | `req` — the finished request; `is_insert` — insert the owned range into the tree (True) or free it (False); `owned_kv_len` — end of the request-owned KV range; slots past it are freed by `release_kv_cache` |
 | **Output** | `None` |
 | **Mutation** | Calls component hooks → `insert` → `dec_lock_ref` → component cleanup. Frees unaligned tail KV indices; frees non-inserted KV indices when `is_insert=False`. |
 | **Complexity** | **O(K + D·C)** — insert O(K + D·C) + lock release O(D). Simplifies to **O(K)**. |
diff --git a/python/sglang/srt/mem_cache/unified_radix_cache.py b/python/sglang/srt/mem_cache/unified_radix_cache.py
index 7b08faa6c..ad6d463ca 100644
--- a/python/sglang/srt/mem_cache/unified_radix_cache.py
+++ b/python/sglang/srt/mem_cache/unified_radix_cache.py
@@ -955,22 +955,22 @@ class UnifiedRadixCache(BasePrefixCache):
             return DecLockRefResult()
         return self.tree_core.dec_host_lock_ref(node_id, params)
 
-    @rank_consensus(same_params=["req.rid", "is_insert", "kv_len_to_handle"])
+    @rank_consensus(same_params=["req.rid", "is_insert", "owned_kv_len"])
     def cache_finished_req(
-        self, req: Req, is_insert: bool = True, *, kv_len_to_handle: int, **kwargs
+        self, req: Req, is_insert: bool = True, *, owned_kv_len: int, **kwargs
     ) -> None:
         if self.session.try_cache_finished_req(req, is_insert=is_insert, **kwargs):
             return
 
         if self.disable:
-            self.free_kv_row(req.kv, [(0, kv_len_to_handle)])
+            self.free_kv_row(req.kv, [(0, owned_kv_len)])
             for comp in self._components_tuple:
                 comp.cleanup_after_caching_req(req, is_finished=True)
             return
 
-        token_ids = (req.origin_input_ids + req.output_ids)[:kv_len_to_handle]
+        token_ids = (req.origin_input_ids + req.output_ids)[:owned_kv_len]
         kv_indices = self.req_to_token_pool.req_to_token[
-            req.kv.req_pool_idx, :kv_len_to_handle
+            req.kv.req_pool_idx, :owned_kv_len
         ]
 
         result = None
@@ -1078,7 +1078,7 @@ class UnifiedRadixCache(BasePrefixCache):
                     ranges.append((tail_free_start, len(kv_indices_full)))
             self.free_kv_row(req.kv, ranges)
         else:
-            self.free_kv_row(req.kv, [(req.kv.cache_protected_len, kv_len_to_handle)])
+            self.free_kv_row(req.kv, [(req.kv.cache_protected_len, owned_kv_len)])
 
         # Synthetic profiling requests may own KV without locking a tree node.
         if req.last_node is not None:
diff --git a/test/registered/unit/disaggregation/test_specv2_kvcache_offloading.py b/test/registered/unit/disaggregation/test_specv2_kvcache_offloading.py
index c366648e4..89d094418 100644
--- a/test/registered/unit/disaggregation/test_specv2_kvcache_offloading.py
+++ b/test/registered/unit/disaggregation/test_specv2_kvcache_offloading.py
@@ -55,7 +55,7 @@ def _make_mock_req(
         kv_allocated_len=kv_allocated_len,
     )
     req.prefix_indices = list(range(prefix_indices_len))
-    req.effective_kv_committed_len = lambda: req.kv.kv_committed_len
+    req.owned_kv_len = lambda: req.kv.kv_committed_len
     return req
 
 
diff --git a/test/registered/unit/mem_cache/test_decode_radix_lock_ref.py b/test/registered/unit/mem_cache/test_decode_radix_lock_ref.py
index af68e287b..4192dcf3a 100644
--- a/test/registered/unit/mem_cache/test_decode_radix_lock_ref.py
+++ b/test/registered/unit/mem_cache/test_decode_radix_lock_ref.py
@@ -234,7 +234,7 @@ class TestDecodeLockRefScenarios(CustomTestCase):
         cache.cache_unfinished_req(req)
 
         # Step 3: cache_finished_req with is_insert=True (dec lock)
-        cache.cache_finished_req(req, kv_len_to_handle=req.kv.kv_committed_len)
+        cache.cache_finished_req(req, owned_kv_len=req.kv.kv_committed_len)
 
         # Verify: all non-root nodes should have lock_ref == 0
         # (root always has lock_ref == 1)
@@ -283,7 +283,7 @@ class TestDecodeLockRefScenarios(CustomTestCase):
         cache.cache_unfinished_req(req)
 
         # Step 3: cache_finished_req (dec leaf)
-        cache.cache_finished_req(req, kv_len_to_handle=req.kv.kv_committed_len)
+        cache.cache_finished_req(req, owned_kv_len=req.kv.kv_committed_len)
 
         # Root lock unchanged, all nodes unlocked
         self.assertEqual(cache.root_node.lock_ref, root_lock_before)
@@ -331,7 +331,7 @@ class TestDecodeLockRefScenarios(CustomTestCase):
         # Transfer fails -> cache_finished_req with is_insert=False
         cache.token_to_kv_pool_allocator.reset_mock()
         cache.cache_finished_req(
-            req, is_insert=False, kv_len_to_handle=req.kv.kv_committed_len
+            req, is_insert=False, owned_kv_len=req.kv.kv_committed_len
         )
 
         free_call = cache.token_to_kv_pool_allocator.free_segment.call_args
@@ -346,6 +346,53 @@ class TestDecodeLockRefScenarios(CustomTestCase):
         # Prefix tokens should still be in tree and evictable
         self.assertEqual(cache.evictable_size(), len(prefix))
 
+    def test_insert_releases_committed_slot_without_token_id(self):
+        """The insert path releases up to owned_kv_len, not len(token_ids).
+
+        Pins the ownership contract on BasePrefixCache.cache_finished_req.
+        """
+        cache, req_to_token = _make_cache_with_pools()
+
+        prefix = [1, 2, 3]
+        prefix_vals = [10, 20, 30]
+        self._populate_prefix(cache, prefix, prefix_vals)
+
+        result = cache.match_prefix(MatchPrefixParams(key=RadixKey(array("q", prefix))))
+        matched_node = result.last_device_node
+        prefix_len = len(result.device_indices)
+        cache.inc_lock_ref(matched_node)
+
+        # Token sequence is 5 long; a 6th KV slot is committed with no token id.
+        full_ids = [1, 2, 3, 4, 5]
+        row_vals = [10, 20, 30, 40, 50, 60]
+        req_to_token[0, : len(row_vals)] = torch.tensor(row_vals, dtype=torch.int64)
+
+        req = _make_req(
+            fill_ids=full_ids,
+            req_pool_idx=0,
+            cache_protected_len=prefix_len,
+            last_node=matched_node,
+        )
+        req.kv.kv_committed_len = len(row_vals)
+        req.kv.kv_allocated_len = len(row_vals)
+
+        cache.token_to_kv_pool_allocator.reset_mock()
+        cache.cache_finished_req(
+            req, is_insert=True, owned_kv_len=req.kv.kv_committed_len
+        )
+
+        # The unnamed tail slot is freed as the segment past the radix key.
+        segments = cache.token_to_kv_pool_allocator.free_segments.call_args.args[0]
+        freed = {
+            int(start_pos) + i: int(v)
+            for indices, start_pos in segments
+            for i, v in enumerate(indices.tolist())
+        }
+        self.assertIn(
+            len(full_ids), freed, "committed slot with no token id was not freed"
+        )
+        self.assertEqual(freed[len(full_ids)], row_vals[-1])
+
     def test_full_transfer_failure(self):
         """Scenario 4: no prefix match, transfer fails.
 
@@ -384,7 +431,7 @@ class TestDecodeLockRefScenarios(CustomTestCase):
         # Transfer fails -> cache_finished_req with is_insert=False
         # dec_lock_ref(root) is a no-op
         cache.cache_finished_req(
-            req, is_insert=False, kv_len_to_handle=req.kv.kv_committed_len
+            req, is_insert=False, owned_kv_len=req.kv.kv_committed_len
         )
 
         # Root lock unchanged, nothing protected or evictable
@@ -572,7 +619,7 @@ class TestDecodeLockRefScenarios(CustomTestCase):
             )
 
             cache.cache_unfinished_req(req)
-            cache.cache_finished_req(req, kv_len_to_handle=req.kv.kv_committed_len)
+            cache.cache_finished_req(req, owned_kv_len=req.kv.kv_committed_len)
 
         # After all iterations, root lock should be 1, no protected nodes
         self.assertEqual(cache.root_node.lock_ref, 1)
diff --git a/test/registered/unit/mem_cache/test_page_interleave_shard.py b/test/registered/unit/mem_cache/test_page_interleave_shard.py
index 508204574..6961f75fc 100644
--- a/test/registered/unit/mem_cache/test_page_interleave_shard.py
+++ b/test/registered/unit/mem_cache/test_page_interleave_shard.py
@@ -768,7 +768,7 @@ class TestRotationGraftDecline(CustomTestCase):
         req = _GraftReq(list(range(8)) + [90, 91, 92, 93])
         req.kv_rotation_base = 3
         own_locs = self._own_row(tree, req, 12)
-        tree.cache_finished_req(req, kv_len_to_handle=12)
+        tree.cache_finished_req(req, owned_kv_len=12)
         released = torch.cat(freed)
         # Everything past the protected prefix is released: the duplicates of
         # the matched region AND the declined tail (nothing leaks, nothing is
@@ -784,7 +784,7 @@ class TestRotationGraftDecline(CustomTestCase):
         req = _GraftReq(list(range(8)) + [90, 91, 92, 93])
         req.kv_rotation_base = 1
         own_locs = self._own_row(tree, req, 12)
-        tree.cache_finished_req(req, kv_len_to_handle=12)
+        tree.cache_finished_req(req, owned_kv_len=12)
         self.assertEqual(_match_len(tree, req.fill_ids), 12)
         released = torch.cat(freed) if freed else torch.empty(0, dtype=torch.int64)
         # Only the 8 duplicate rows go back; the tail stays live in the tree.
diff --git a/test/registered/unit/mem_cache/test_pure_swa_chunk_cache.py b/test/registered/unit/mem_cache/test_pure_swa_chunk_cache.py
index 39acb211c..6fd818a16 100644
--- a/test/registered/unit/mem_cache/test_pure_swa_chunk_cache.py
+++ b/test/registered/unit/mem_cache/test_pure_swa_chunk_cache.py
@@ -45,7 +45,7 @@ class TestPureSWAChunkCache(CustomTestCase):
     def test_finished_req_skips_already_evicted_swa_range(self):
         cache = self._make_cache()
 
-        cache.cache_finished_req(_FakeReq(), kv_len_to_handle=8)
+        cache.cache_finished_req(_FakeReq(), owned_kv_len=8)
 
         self.assertEqual(len(cache.token_to_kv_pool_allocator.freed), 1)
         freed = cache.token_to_kv_pool_allocator.freed[0]
@@ -56,7 +56,7 @@ class TestPureSWAChunkCache(CustomTestCase):
         req = _FakeReq()
         req.kv.cache_protected_len = 2
 
-        cache.cache_finished_req(req, kv_len_to_handle=8)
+        cache.cache_finished_req(req, owned_kv_len=8)
 
         freed = cache.token_to_kv_pool_allocator.freed[0]
         self.assertTrue(torch.equal(freed, torch.tensor([2, 6, 7])))
diff --git a/test/registered/unit/mem_cache/test_pure_swa_radix_cache.py b/test/registered/unit/mem_cache/test_pure_swa_radix_cache.py
index b9f108dd1..25d3911cf 100644
--- a/test/registered/unit/mem_cache/test_pure_swa_radix_cache.py
+++ b/test/registered/unit/mem_cache/test_pure_swa_radix_cache.py
@@ -26,7 +26,6 @@ class TestPureSWARadixCache(CustomTestCase):
     def test_no_insert_frees_window_after_evict_floor_before_swa_eviction(self):
         allocator = _FakeAllocator()
         cache = PureSWARadixCache.__new__(PureSWARadixCache)
-        cache.disable_finished_insert = False
         cache.disable = False
         cache.is_eagle = False
         cache.page_size = 1
@@ -48,7 +47,7 @@ class TestPureSWARadixCache(CustomTestCase):
             ),
         )
 
-        cache.cache_finished_req(req, is_insert=False, kv_len_to_handle=8)
+        cache.cache_finished_req(req, is_insert=False, owned_kv_len=8)
 
         self.assertEqual(allocator.freed, [[0, 1, 2, 3], [4, 5, 6, 7]])
 
diff --git a/test/registered/unit/mem_cache/test_radix_cache_unit.py b/test/registered/unit/mem_cache/test_radix_cache_unit.py
index 29e94d89d..49319dfcf 100644
--- a/test/registered/unit/mem_cache/test_radix_cache_unit.py
+++ b/test/registered/unit/mem_cache/test_radix_cache_unit.py
@@ -572,7 +572,7 @@ class TestRadixCache(CustomTestCase):
         cache.cache_finished_req(
             req,
             is_insert=True,
-            kv_len_to_handle=len(prompt_ids) + len(output_ids),
+            owned_kv_len=len(prompt_ids) + len(output_ids),
         )
 
         (prompt_node,) = cache.root_node.children.values()
diff --git a/test/registered/unit/mem_cache/test_swa_eviction_boundary.py b/test/registered/unit/mem_cache/test_swa_eviction_boundary.py
index 7462c2cf7..e486db1fd 100644
--- a/test/registered/unit/mem_cache/test_swa_eviction_boundary.py
+++ b/test/registered/unit/mem_cache/test_swa_eviction_boundary.py
@@ -191,7 +191,7 @@ class TestSWAEvictionBoundary(unittest.TestCase):
             self.assertLess(req.kv.swa_evicted_seqlen, insert_len)
 
             tree.cache_finished_req(
-                req, is_insert=True, kv_len_to_handle=req._kv_committed_len
+                req, is_insert=True, owned_kv_len=req._kv_committed_len
             )
             tree.sanity_check()
 
@@ -358,7 +358,7 @@ class TestSWAEvictionBoundary(unittest.TestCase):
             )
 
             tree.cache_finished_req(
-                req, is_insert=True, kv_len_to_handle=req._kv_committed_len
+                req, is_insert=True, owned_kv_len=req._kv_committed_len
             )
             tree.sanity_check()
 
@@ -397,7 +397,7 @@ class TestSWAEvictionBoundary(unittest.TestCase):
         pool.write((0, slice(0, first_len)), kv1)
         req1 = _make_req(0, list(range(first_len)), 0, tree)
         tree.cache_finished_req(
-            req1, is_insert=True, kv_len_to_handle=req1._kv_committed_len
+            req1, is_insert=True, owned_kv_len=req1._kv_committed_len
         )
         tree.sanity_check()
 
@@ -415,7 +415,7 @@ class TestSWAEvictionBoundary(unittest.TestCase):
 
         swa_evictable_before = tree.swa_evictable_size_
         tree.cache_finished_req(
-            req2, is_insert=True, kv_len_to_handle=req2._kv_committed_len
+            req2, is_insert=True, owned_kv_len=req2._kv_committed_len
         )
 
         # New tokens [16, 24) should all be non-tombstone
@@ -447,9 +447,7 @@ class TestSWAEvictionBoundary(unittest.TestCase):
         self.assertGreater(req.kv.swa_evicted_seqlen, 0, "Should have some eviction")
         self.assertLess(req.kv.swa_evicted_seqlen, insert_len, "Should be partial")
 
-        tree.cache_finished_req(
-            req, is_insert=True, kv_len_to_handle=req._kv_committed_len
-        )
+        tree.cache_finished_req(req, is_insert=True, owned_kv_len=req._kv_committed_len)
 
         non_tombstone = insert_len - req.kv.swa_evicted_seqlen
         self.assertEqual(tree.swa_evictable_size_, swa_evictable_before + non_tombstone)
@@ -487,9 +485,7 @@ class TestSWAEvictionBoundary(unittest.TestCase):
         req.kv.swa_evicted_seqlen = old_evicted
         swa_evictable_before = tree.swa_evictable_size_
 
-        tree.cache_finished_req(
-            req, is_insert=True, kv_len_to_handle=req._kv_committed_len
-        )
+        tree.cache_finished_req(req, is_insert=True, owned_kv_len=req._kv_committed_len)
 
         self.assertEqual(tree.swa_evictable_size_, swa_evictable_before)
 
@@ -519,7 +515,7 @@ class TestSWAEvictionBoundary(unittest.TestCase):
             self.assertLess(req.kv.swa_evicted_seqlen, insert_len, f"turn {turn}")
 
             tree.cache_finished_req(
-                req, is_insert=True, kv_len_to_handle=req._kv_committed_len
+                req, is_insert=True, owned_kv_len=req._kv_committed_len
             )
             tree.sanity_check()
 
@@ -545,7 +541,7 @@ class TestSWAEvictionBoundary(unittest.TestCase):
             )
 
             tree.cache_finished_req(
-                req, is_insert=True, kv_len_to_handle=req._kv_committed_len
+                req, is_insert=True, owned_kv_len=req._kv_committed_len
             )
             tree.sanity_check()
 
diff --git a/test/registered/unit/mem_cache/test_swa_unittest.py b/test/registered/unit/mem_cache/test_swa_unittest.py
index 65c9b815e..6b0cca4a8 100644
--- a/test/registered/unit/mem_cache/test_swa_unittest.py
+++ b/test/registered/unit/mem_cache/test_swa_unittest.py
@@ -813,9 +813,7 @@ class TestSWA(unittest.TestCase):
             return original_insert(params)
 
         tree.insert = wrapped_insert
-        tree.cache_finished_req(
-            req, is_insert=True, kv_len_to_handle=req._kv_committed_len
-        )
+        tree.cache_finished_req(req, is_insert=True, owned_kv_len=req._kv_committed_len)
 
         self.assertEqual(captured["prev_prefix_len"], req.kv.cache_protected_len)
         self.assertTrue(captured["is_bigram"])
@@ -849,7 +847,7 @@ class TestSWA(unittest.TestCase):
 
         allocator.free_segment = wrapped_free_segment
         tree.cache_finished_req(
-            req2, is_insert=False, kv_len_to_handle=req2._kv_committed_len
+            req2, is_insert=False, owned_kv_len=req2._kv_committed_len
         )
 
         # EAGLE + page_size=1 => page_aligned_len = committed_len - 1 = 5
@@ -1465,7 +1463,7 @@ class TestCacheUnfinishedReqEvictedPrefix(CustomTestCase):
 
         # Finishing drops the locks, which sanity_check needs; the accounting
         # must survive the re-walk.
-        tree.cache_finished_req(req, kv_len_to_handle=num_tokens)
+        tree.cache_finished_req(req, owned_kv_len=num_tokens)
         self.assertEqual(allocator.swa_available_size(), swa_before)
         self.assertEqual(
             tree.swa_evictable_size_ + tree.swa_protected_size_,
diff --git a/test/registered/unit/mem_cache/test_unified_radix_cache_bench.py b/test/registered/unit/mem_cache/test_unified_radix_cache_bench.py
index 95460dc3c..c88f6e9a2 100644
--- a/test/registered/unit/mem_cache/test_unified_radix_cache_bench.py
+++ b/test/registered/unit/mem_cache/test_unified_radix_cache_bench.py
@@ -662,7 +662,7 @@ def bench_cache_finished(
         "cache_finished",
         lambda: req_items,
         lambda req: env.tree.cache_finished_req(
-            req, is_insert=True, kv_len_to_handle=req.kv.kv_committed_len
+            req, is_insert=True, owned_kv_len=req.kv.kv_committed_len
         ),
         len(req_items) - warmup,
         env.avg_tokens,
diff --git a/test/registered/unit/mem_cache/test_unified_radix_cache_unittest.py b/test/registered/unit/mem_cache/test_unified_radix_cache_unittest.py
index 08b3a097c..749b547a7 100644
--- a/test/registered/unit/mem_cache/test_unified_radix_cache_unittest.py
+++ b/test/registered/unit/mem_cache/test_unified_radix_cache_unittest.py
@@ -1668,9 +1668,7 @@ class UnifiedRadixCacheSuite:
         if self.cfg.has_mamba:
             req.kv.mamba_last_track_seqlen = kv_len
 
-        cache.cache_finished_req(
-            req, is_insert=True, kv_len_to_handle=req.effective_kv_committed_len()
-        )
+        cache.cache_finished_req(req, is_insert=True, owned_kv_len=req.owned_kv_len())
 
         all_ids = input_ids + output_ids
         aligned_len = (len(all_ids) // ps) * ps
@@ -1732,9 +1730,9 @@ class UnifiedRadixCacheSuite:
         with get_serving().override(strip_thinking_cache=True):
             avail_before = allocator.available_size()
             cache.cache_finished_req(
-                req, is_insert=True, kv_len_to_handle=req.effective_kv_committed_len()
+                req, is_insert=True, owned_kv_len=req.owned_kv_len()
             )
-            start_p, end_p = req.effective_kv_committed_len(), req.kv.kv_allocated_len
+            start_p, end_p = req.owned_kv_len(), req.kv.kv_allocated_len
         if ps > 1:
             start_p = ((start_p + ps - 1) // ps) * ps
         if start_p < end_p:
@@ -1775,9 +1773,7 @@ class UnifiedRadixCacheSuite:
         )
 
         avail_before = allocator.available_size()
-        cache.cache_finished_req(
-            req, is_insert=False, kv_len_to_handle=req.effective_kv_committed_len()
-        )
+        cache.cache_finished_req(req, is_insert=False, owned_kv_len=req.owned_kv_len())
 
         self.assertEqual(allocator.available_size(), avail_before + kv_len)
         m = cache.match_prefix(MatchPrefixParams(key=RadixKey(array("q", tokens))))
@@ -1952,9 +1948,7 @@ class UnifiedRadixCacheSuite:
             req.kv.mamba_last_track_seqlen = kv_len
 
         avail_before = allocator.available_size()
-        cache.cache_finished_req(
-            req, is_insert=True, kv_len_to_handle=req.effective_kv_committed_len()
-        )
+        cache.cache_finished_req(req, is_insert=True, owned_kv_len=req.owned_kv_len())
 
         self.assertEqual(allocator.available_size(), avail_before + tail_extra)
         aligned = input_ids[: (len(input_ids) // ps) * ps]
@@ -8408,9 +8402,7 @@ class TestUnifiedRadixCacheInt8MambaCheckpoint(CustomTestCase):
         )
         req.last_node = cache.root_node_handle()
 
-        cache.cache_finished_req(
-            req, is_insert=True, kv_len_to_handle=req.effective_kv_committed_len()
-        )
+        cache.cache_finished_req(req, is_insert=True, owned_kv_len=req.owned_kv_len())
 
     def test_finished_req_stores_radix_mamba_state_in_int8_pool(self):
         cache, allocator, req_to_token_pool = build_fixture(self.cfg)
diff --git a/test/registered/unit/mem_cache/test_unified_radix_lock_ref.py b/test/registered/unit/mem_cache/test_unified_radix_lock_ref.py
index 8899d2820..0feb87d6a 100644
--- a/test/registered/unit/mem_cache/test_unified_radix_lock_ref.py
+++ b/test/registered/unit/mem_cache/test_unified_radix_lock_ref.py
@@ -35,7 +35,7 @@ class TestUnifiedRadixLockRefScenarios(unittest.TestCase):
             swa_prefix_lock_released=False,
         )
 
-        cache.cache_finished_req(req, is_insert=False, kv_len_to_handle=3)
+        cache.cache_finished_req(req, is_insert=False, owned_kv_len=3)
 
         cache.free_kv_row.assert_called_once_with(kv, [(0, 3)])
         cache._dec_req_lock.assert_not_called()
diff --git a/test/registered/xpu/test_lmcache_radix_cache.py b/test/registered/xpu/test_lmcache_radix_cache.py
index fb2ee18f9..bf8842b19 100644
--- a/test/registered/xpu/test_lmcache_radix_cache.py
+++ b/test/registered/xpu/test_lmcache_radix_cache.py
@@ -193,7 +193,7 @@ class TestLMCRadixCacheXPU(unittest.TestCase):
                 gt_v.append(v.clone())
 
             req = _make_req("req-0", req_pool_idx, token_ids, tree)
-            tree.cache_finished_req(req, kv_len_to_handle=len(token_ids))
+            tree.cache_finished_req(req, owned_kv_len=len(token_ids))
             # IP-mode store is async on tree.store_stream; evict()'s
             # synchronize() is what the real scheduler relies on to make the
             # store visible before slots are reused.