diff --git a/turnstone/core/lowering.py b/turnstone/core/lowering.py
index c40c548e..d339b46d 100644
--- a/turnstone/core/lowering.py
+++ b/turnstone/core/lowering.py
@@ -308,7 +308,7 @@ _WIRE_TOOL_ID_RE = re.compile(r"[a-zA-Z0-9_-]{1,40}")
 def wire_safe_tool_call_id(tc_id: str) -> str:
     """Return *tc_id* unchanged if it already matches the conservative
     wire-legal shape (:data:`_WIRE_TOOL_ID_RE`), else a deterministic safe
-    token (``tid_`` + 32 hex chars of its SHA-1, 36 chars total).
+    token (``tid_`` + 32 hex chars of its SHA-256, 36 chars total).
 
     Determinism is the contract: the same original id maps to the same token
     in the assistant ``tool_use`` and its ``tool_result`` (intra-request
@@ -320,7 +320,7 @@ def wire_safe_tool_call_id(tc_id: str) -> str:
     """
     if _WIRE_TOOL_ID_RE.fullmatch(tc_id):
         return tc_id
-    return "tid_" + hashlib.sha1(tc_id.encode("utf-8", "surrogatepass")).hexdigest()[:32]
+    return "tid_" + hashlib.sha256(tc_id.encode("utf-8", "surrogatepass")).hexdigest()[:32]
 
 
 def legalize_tool_call_ids(messages: list[dict[str, Any]]) -> list[dict[str, Any]]:
diff --git a/turnstone/shared_static/interactive.js b/turnstone/shared_static/interactive.js
index 956e8eff..1954530b 100644
--- a/turnstone/shared_static/interactive.js
+++ b/turnstone/shared_static/interactive.js
@@ -653,7 +653,7 @@ class Pane {
     if (!el) {
       let target = this._toolRow(callId);
       if (!target) {
-        // A minted sub-agent child id ("<parent>::<seq>::<id>") whose row hasn't
+        // A minted sub-agent child id ("<parent>::r{run}s{step}::<id>") whose row hasn't
         // nested yet must NOT graft its stream onto the last top-level batch —
         // that mislabels a sub-tool's output as a main-harness tool's.  Its row
         // arrives via the orphan flush; skip the chunk until then.
@@ -3491,7 +3491,7 @@ class Pane {
     }
     let target = this._toolRow(callId);
     if (!target) {
-      // A minted sub-agent child id ("<parent>::<seq>::<id>") whose row hasn't
+      // A minted sub-agent child id ("<parent>::r{run}s{step}::<id>") whose row hasn't
       // nested yet must NOT graft its output onto the last top-level batch row
       // — that mislabels a sub-tool's result as a main-harness tool's.  Its row
       // arrives via the orphan flush; skip until then.