diff --git a/CHANGELOG.md b/CHANGELOG.md
index 191c259..ed121bb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -29,6 +29,7 @@ The format is based on Keep a Changelog, and this project currently tracks chang
 - Fixed duplicate response in React TUI caused by double Enter key submission in the input handler.
 - Fixed concurrent permission modals overwriting each other in TUI default mode when the LLM returns multiple tool calls in one response; `_ask_permission` now serialises callers via an `asyncio.Lock` so each modal is shown and resolved before the next one is emitted.
 - Fixed React TUI Markdown tables to size columns from rendered cell text so inline formatting like code spans and bold text no longer breaks alignment.
+- Fixed grep tool crashing with `ValueError` / `LimitOverrunError` when ripgrep outputs a line longer than 64 KB (e.g. minified assets or lock files). The asyncio subprocess stream limit is now 8 MB and oversized lines are skipped rather than terminating the session.
 
 ### Changed
 
diff --git a/src/openharness/tools/grep_tool.py b/src/openharness/tools/grep_tool.py
index b4416cf..bef0943 100644
--- a/src/openharness/tools/grep_tool.py
+++ b/src/openharness/tools/grep_tool.py
@@ -183,6 +183,7 @@ async def _rg_grep(
         cwd=str(root),
         stdout=asyncio.subprocess.PIPE,
         stderr=asyncio.subprocess.PIPE,
+        limit=8 * 1024 * 1024,  # 8 MB per line — avoids LimitOverrunError on long lines
     )
 
     matches: list[str] = []
@@ -239,6 +240,7 @@ async def _rg_grep_file(
         cwd=str(path.parent),
         stdout=asyncio.subprocess.PIPE,
         stderr=asyncio.subprocess.PIPE,
+        limit=8 * 1024 * 1024,  # 8 MB per line — avoids LimitOverrunError on long lines
     )
 
     matches: list[str] = []
@@ -282,7 +284,11 @@ async def _collect_rg_matches(
 ) -> None:
     assert process.stdout is not None
     while len(matches) < limit:
-        raw = await process.stdout.readline()
+        try:
+            raw = await process.stdout.readline()
+        except ValueError:
+            # Line exceeded the stream buffer limit; skip it and continue.
+            continue
         if not raw:
             break
         line = raw.decode("utf-8", errors="replace").rstrip("\n")
@@ -300,7 +306,11 @@ async def _collect_rg_file_matches(
 ) -> None:
     assert process.stdout is not None
     while len(matches) < limit:
-        raw = await process.stdout.readline()
+        try:
+            raw = await process.stdout.readline()
+        except ValueError:
+            # Line exceeded the stream buffer limit; skip it and continue.
+            continue
         if not raw:
             break
         line = raw.decode("utf-8", errors="replace").rstrip("\n")