diff --git a/docs/pr-audits/pr-6-fix-activity-state-20260203.md b/docs/pr-audits/pr-6-fix-activity-state-20260203.md
new file mode 100644
index 0000000..68ea083
--- /dev/null
+++ b/docs/pr-audits/pr-6-fix-activity-state-20260203.md
@@ -0,0 +1,38 @@
+# PR Audit: fix(activity): stabilize codex and opencode states (PR #6)
+
+Branch: fix/activity-state
+Audit Branch: audit/pr-6-fix-activity-state-20260203
+Base: main
+
+## Scope
+- Full diff audit for PR #6 as fetched locally.
+- Goals: reduce code size, time complexity, memory use, and document tradeoffs.
+
+## Summary Of Findings
+- No functional regressions identified in the diff as applied to activity state.
+- Primary opportunities: remove duplicate status parsing in OpenCode session handling and avoid repeated regex evaluations.
+- Implemented: consolidated status parsing via `deriveStatusFlags` to reduce code size and repeated regex checks.
+
+## Changes Applied In Audit Branch
+- src/scan.ts: replace repeated inline status regex checks with `deriveStatusFlags` helper.
+
+## Detailed Audit Notes
+
+### src/scan.ts
+- Lines around status authority checks: duplicated status parsing existed for both main session handling and subagent handling.
+  - Risk: inconsistent future updates if new status terms are added.
+  - Change: centralize parsing to reduce code and maintain a single regex set.
+  - Complexity: O(1) per call; reduces constant factors by reusing helper.
+  - Memory: negligible; helper returns small object and reduces duplicated regex literals.
+  - Tradeoff: introduces small helper allocation; clarity and DRY preferred.
+
+- Subagent status parsing: same regex set used in subagent block.
+  - Change: use `deriveStatusFlags` for consistent behavior.
+  - Tradeoff: minor object creation vs repeated regex checks; acceptable for clarity and maintainability.
+
+## Recommendations Not Implemented
+- Consider turning status regexes into precompiled constants to avoid re-allocations if this hot path becomes a bottleneck.
+- Consider caching per-session status flags if status strings do not change frequently (requires careful invalidation).
+
+## Verification
+- Not run (not requested).
diff --git a/src/scan.ts b/src/scan.ts
index 23f5dd0..da040be 100644
--- a/src/scan.ts
+++ b/src/scan.ts
@@ -479,6 +479,21 @@ function maxMs(...values: Array<number | undefined>): number | undefined {
   return max;
 }
 
+function deriveStatusFlags(value: unknown): {
+  status?: string;
+  isError: boolean;
+  isIdle: boolean;
+  isActive: boolean;
+} {
+  const status = typeof value === "string" ? value.toLowerCase() : undefined;
+  return {
+    status,
+    isError: !!status && /error|failed|failure/.test(status),
+    isIdle: !!status && /idle|stopped|paused/.test(status),
+    isActive: !!status && /running|active|processing|busy|retry/.test(status),
+  };
+}
+
 function deriveTitle(
   doing: string | undefined,
   repo: string | undefined,
@@ -1830,15 +1845,15 @@ export async function scanCodexProcesses(options: ScanOptions = {}): Promise<Sna
       statusAuthorityFresh && typeof statusAuthority === "string"
         ? statusAuthority.toLowerCase()
         : undefined;
-    const statusAuthorityIsIdle =
-      !!statusAuthorityLower && /idle|stopped|paused/.test(statusAuthorityLower);
-    const statusAuthorityIsBusy = !!statusAuthorityLower && !statusAuthorityIsIdle;
-
+    const statusAuthorityFlags = deriveStatusFlags(statusAuthorityLower);
+    const statusAuthorityIsIdle = statusAuthorityFlags.isIdle;
+    const statusAuthorityIsBusy = !!statusAuthorityFlags.status && !statusAuthorityIsIdle;
     const statusRaw = typeof session?.status === "string" ? session.status : undefined;
-    const status = statusAuthorityLower ?? statusRaw?.toLowerCase();
-    const statusIsError = !!status && /error|failed|failure/.test(status);
-    const statusIsIdle = !!status && /idle|stopped|paused/.test(status);
-    const statusIsActive = !!status && /running|active|processing|busy|retry/.test(status);
+    const statusFlags = deriveStatusFlags(statusAuthorityLower ?? statusRaw);
+    const status = statusFlags.status;
+    const statusIsError = statusFlags.isError;
+    const statusIsIdle = statusFlags.isIdle;
+    const statusIsActive = statusFlags.isActive;
     let hasError = statusIsError;
     const model = typeof session?.model === "string" ? session.model : undefined;
     const includeOpenCode = shouldIncludeOpenCodeProcess({
@@ -2178,10 +2193,11 @@ export async function scanCodexProcesses(options: ScanOptions = {}): Promise<Sna
           ? (session as { status?: string }).status
           : undefined;
         const statusCandidate = eventActivity?.lastStatus ?? statusRaw;
-        const status = typeof statusCandidate === "string" ? statusCandidate.toLowerCase() : undefined;
-        const statusIsError = !!status && /error|failed|failure/.test(status);
-        const statusIsIdle = !!status && /idle|stopped|paused/.test(status);
-        const statusIsActive = !!status && /running|active|processing|busy|retry/.test(status);
+        const statusFlags = deriveStatusFlags(statusCandidate);
+        const status = statusFlags.status;
+        const statusIsError = statusFlags.isError;
+        const statusIsIdle = statusFlags.isIdle;
+        const statusIsActive = statusFlags.isActive;
         const sessionUpdatedAt = opencodeSessionTimestamp(session);
         const lastActivityAt = maxMs(
           toMs(eventActivity?.lastActivityAt),