cherry-pick(pr-9735): feat(logging): bump CHAT_LOG_ARRAY_TAIL_ITEMS default 24 -> 128

.env.example

@@ -1426,7 +1426,7 @@ APP_LOG_TO_FILE=true
 # bodies is retained in the database.
 # Used by: open-sse/handlers/chatCore.ts — cloneBoundedChatLogPayload()
 # CHAT_LOG_TEXT_LIMIT=65536                  # Max string length before truncation (default: 64 KB)
-# CHAT_LOG_ARRAY_TAIL_ITEMS=24               # Number of array items retained from tail (default: 24)
+# CHAT_LOG_ARRAY_TAIL_ITEMS=128               # Number of array items retained from tail (default: 128)
 # CHAT_LOG_MAX_DEPTH=6                       # Max nesting depth before truncation (default: 6)
 # CHAT_LOG_MAX_OBJECT_KEYS=80                # Max object keys retained (default: 80, 0 = no limit)
 

docs/reference/ENVIRONMENT.md

@@ -741,7 +741,7 @@ The logging system writes to both stdout and rotated log files. All configuratio
 | `PROXY_LOGS_TABLE_MAX_ROWS`               | `100000`                   | Max rows in the `proxy_logs` SQLite table before pruning.                         |
 | `APP_LOG_ROTATION_CHECK_INTERVAL_MS`      | `60000` (1 min)            | How often `src/lib/logRotation.ts` re-checks the active log file size.            |
 | `CHAT_LOG_TEXT_LIMIT`                     | `65536`                    | Max string length retained in chat log artifacts (default 64 KB).                 |
-| `CHAT_LOG_ARRAY_TAIL_ITEMS`               | `24`                       | Number of array items retained from the tail when truncating chat log payloads.   |
+| `CHAT_LOG_ARRAY_TAIL_ITEMS`               | `128`                      | Number of array items retained from the tail when truncating chat log payloads.   |
 | `CHAT_LOG_MAX_DEPTH`                      | `6`                        | Max nesting depth before chat log payloads are truncated.                         |
 | `CHAT_LOG_MAX_OBJECT_KEYS`                | `80`                       | Max object keys retained in chat log payloads (0 = unlimited).                    |
 | `CHAT_DEBUG_FILE`                         | `false`                    | When true, `serializeArtifactForStorage` skips size-based truncation. Debug only. |

src/lib/logEnv.ts

@@ -146,8 +146,19 @@ export function getChatLogTextLimit(): number {
   return parsePositiveInt(process.env.CHAT_LOG_TEXT_LIMIT, 64 * 1024);
 }
 
+/**
+ * Was a hardcoded/default 24 — real agentic CLIs with many MCP servers
+ * routinely declare 40-50+ tools in a single `tools[]` array (a live
+ * OpenClaw session logged 47), so the tail-24 default silently dropped the
+ * array's earlier entries behind an `_omniroute_truncated_array` marker —
+ * including, in one traced case, the tool actually being called
+ * (`apply_patch`), making its declared shape unrecoverable from the call
+ * log even though the call itself succeeded. Bumped to comfortably cover
+ * real large tool lists with headroom; same configurable-override pattern
+ * as the sibling CHAT_LOG_TEXT_LIMIT/CHAT_LOG_MAX_BODY_KB vars.
+ */
 export function getChatLogArrayTailItems(): number {
-  return parsePositiveInt(process.env.CHAT_LOG_ARRAY_TAIL_ITEMS, 24);
+  return parsePositiveInt(process.env.CHAT_LOG_ARRAY_TAIL_ITEMS, 128);
 }
 
 export function getChatLogMaxDepth(): number {

tests/unit/chat-log-array-tail-items-default.test.ts

@@ -0,0 +1,27 @@
+/**
+ * Regression test for the CHAT_LOG_ARRAY_TAIL_ITEMS default bump 24 -> 128.
+ *
+ * Real agentic CLIs with many MCP servers routinely declare 40-50+ tools in
+ * a single request — a live OpenClaw session logged 47. The old tail-24
+ * default silently dropped the array's earlier entries behind an
+ * `_omniroute_truncated_array` marker, including (in one traced case) the
+ * tool actually being called, making its declared shape unrecoverable from
+ * the call log even though the call itself succeeded.
+ *
+ * Pins the literal default so a future edit can't silently regress it back
+ * toward the old, too-small value.
+ */
+import { test } from "node:test";
+import assert from "node:assert/strict";
+import { getChatLogArrayTailItems } from "@/lib/logEnv";
+
+test("getChatLogArrayTailItems defaults to 128 (not the old 24) when unset", () => {
+  const saved = process.env.CHAT_LOG_ARRAY_TAIL_ITEMS;
+  delete process.env.CHAT_LOG_ARRAY_TAIL_ITEMS;
+  try {
+    assert.equal(getChatLogArrayTailItems(), 128);
+  } finally {
+    if (saved === undefined) delete process.env.CHAT_LOG_ARRAY_TAIL_ITEMS;
+    else process.env.CHAT_LOG_ARRAY_TAIL_ITEMS = saved;
+  }
+});