diff --git a/docs/control/reference/rest_api/headers/security_config.md b/docs/control/reference/rest_api/headers/security_config.md
index 6668549..70929fa 100644
--- a/docs/control/reference/rest_api/headers/security_config.md
+++ b/docs/control/reference/rest_api/headers/security_config.md
@@ -12,7 +12,7 @@ This header is **optional** and can be used in Headers-Only Mode to fine-tune se
     "min_num_tools_for_filtering": 10,
     "clear_session_meta": "never",
     "max_n_turns": null,
-    "allow_history_mismatch": null,
+    "history_mismatch_policy": null,
     "clear_history_every_n_attempts": null,
     "disable_rllm": true,
     "enable_multistep_planning": null,
@@ -110,13 +110,17 @@ Maximum number of turns allowed in the session. If `null`, unlimited turns are a
 
 ### Dual-LLM Only Fields
 
-#### `fsm.allow_history_mismatch`
+#### `fsm.history_mismatch_policy`
 
 | Type | Required | Default |
 |------|----------|---------|
-| `boolean` or `null` | No | `null` |
+| `string` or `null` | No | `null` |
+
+Controls behaviour when incoming messages diverge from stored history in stateless mode:
 
-Controls behaviour when incoming messages diverge from stored history in stateless mode. When `true`, the server silently truncates its stored history to the last consistent point and accepts the caller's version. When `false`, the server rejects the request with an error if a mismatch is detected.
+- `"reject"`: Reject the request with an error if a mismatch is detected
+- `"restart_turn"`: Truncate stored history to the last consistent point and restart the turn
+- `"continue"`: Silently accept the caller's version and continue
 
 #### `fsm.clear_history_every_n_attempts`
 
diff --git a/src/sequrity/control/types/headers.py b/src/sequrity/control/types/headers.py
index 85be974..785a5a9 100644
--- a/src/sequrity/control/types/headers.py
+++ b/src/sequrity/control/types/headers.py
@@ -369,9 +369,9 @@ class FsmOverrides(BaseModel):
     )
 
     # Dual-LLM only
-    allow_history_mismatch: bool | None = Field(
+    history_mismatch_policy: Literal["reject", "restart_turn", "continue"] | None = Field(
         default=None,
-        description="Controls behaviour when incoming messages diverge from stored history in stateless mode. When True, the server silently truncates its stored history to the last consistent point. When False, the server rejects the request with an error if a mismatch is detected.",
+        description="Controls behaviour when incoming messages diverge from stored history in stateless mode. 'reject' rejects the request with an error, 'restart_turn' truncates stored history to the last consistent point and restarts the turn, 'continue' silently accepts the caller's version and continues.",
     )
     clear_history_every_n_attempts: int | None = Field(
         default=None,