diff --git a/VERSION b/VERSION
index b616048..844f6a9 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.6.2
+0.6.3
diff --git a/larry.sh b/larry.sh
index ca5ec07..edb41c4 100755
--- a/larry.sh
+++ b/larry.sh
@@ -36,7 +36,7 @@ set -o pipefail
 # ─────────────────────────────────────────────────────────────────────────────
 # Config
 # ─────────────────────────────────────────────────────────────────────────────
-LARRY_VERSION="0.6.2"
+LARRY_VERSION="0.6.3"
 LARRY_HOME="${LARRY_HOME:-$HOME/.larry}"
 LARRY_BASE_URL="${LARRY_BASE_URL:-https://raw.githubusercontent.com/bojj27/cloverleaf-larry/main}"
 LARRY_UPDATE_URL="${LARRY_UPDATE_URL:-${LARRY_BASE_URL}/larry.sh}"
@@ -457,23 +457,37 @@ log_append()  { printf '%s\n' "$1" >> "$LOG_FILE"; }
 # On MobaXterm/Cygwin the bundled jq is a Windows-native binary that can't
 # resolve Cygwin paths like /home/mobaxterm/... when they come in as argv.
 # Stdin redirection always works because bash does the path open() itself.
+# Each of these passes the value through a tempfile (--rawfile / --slurpfile)
+# rather than argv (--arg / --argjson). Argv overflow ("Argument list too
+# long") on Cygwin's ~32KB total cap was the v0.6.1 bug for TOOLS_JSON; the
+# same pattern applies to any value that could grow with user input or
+# assistant output (multi-paragraph prompts, large tool results, etc.).
 add_user_text() {
   local content="$1"
-  local tmp; tmp=$(mktemp)
-  jq --arg c "$content" '. + [{"role":"user","content":[{"type":"text","text":$c}]}]' < "$MESSAGES_FILE" > "$tmp" \
+  local cfile tmp
+  cfile=$(mktemp); tmp=$(mktemp)
+  printf '%s' "$content" > "$cfile"
+  jq --rawfile c "$cfile" '. + [{"role":"user","content":[{"type":"text","text":$c}]}]' < "$MESSAGES_FILE" > "$tmp" \
     && mv "$tmp" "$MESSAGES_FILE"
+  rm -f "$cfile"
 }
 add_assistant_blocks() {
   local blocks="$1"
-  local tmp; tmp=$(mktemp)
-  jq --argjson b "$blocks" '. + [{"role":"assistant","content":$b}]' < "$MESSAGES_FILE" > "$tmp" \
+  local bfile tmp
+  bfile=$(mktemp); tmp=$(mktemp)
+  printf '%s' "$blocks" > "$bfile"
+  jq --slurpfile b "$bfile" '. + [{"role":"assistant","content":$b[0]}]' < "$MESSAGES_FILE" > "$tmp" \
     && mv "$tmp" "$MESSAGES_FILE"
+  rm -f "$bfile"
 }
 add_user_tool_results() {
   local blocks="$1"
-  local tmp; tmp=$(mktemp)
-  jq --argjson b "$blocks" '. + [{"role":"user","content":$b}]' < "$MESSAGES_FILE" > "$tmp" \
+  local bfile tmp
+  bfile=$(mktemp); tmp=$(mktemp)
+  printf '%s' "$blocks" > "$bfile"
+  jq --slurpfile b "$bfile" '. + [{"role":"user","content":$b[0]}]' < "$MESSAGES_FILE" > "$tmp" \
     && mv "$tmp" "$MESSAGES_FILE"
+  rm -f "$bfile"
 }
 
 # ─────────────────────────────────────────────────────────────────────────────
@@ -1040,17 +1054,19 @@ build_system_prompt() {
 # ─────────────────────────────────────────────────────────────────────────────
 agent_turn() {
   local system_prompt="$1"
-  # Write the TOOLS_JSON to a file ONCE per agent_turn rather than passing it
-  # via --argjson (which puts the full 21KB blob on the jq command line and
-  # blows up Cygwin/Windows argv limits with E2BIG / "Argument list too long").
-  local tools_file; tools_file=$(mktemp)
-  printf '%s' "$TOOLS_JSON" > "$tools_file"
+  # Write the large blobs to files ONCE per agent_turn rather than passing
+  # them via --arg / --argjson. Combined budget (TOOLS_JSON ~21KB + system
+  # prompt ~25KB) easily exceeds Cygwin's ~32KB argv cap → E2BIG.
+  local tools_file system_file
+  tools_file=$(mktemp); system_file=$(mktemp)
+  printf '%s' "$TOOLS_JSON"     > "$tools_file"
+  printf '%s' "$system_prompt"  > "$system_file"
   while true; do
     local payload_file; payload_file=$(mktemp)
     jq -n \
       --arg model "$LARRY_MODEL" \
       --argjson max_tokens "$LARRY_MAX_TOKENS" \
-      --arg system "$system_prompt" \
+      --rawfile system "$system_file" \
       --slurpfile messages "$MESSAGES_FILE" \
       --slurpfile tools "$tools_file" \
       '{model:$model, max_tokens:$max_tokens, system:$system, messages:$messages[0], tools:$tools[0]}' \
@@ -1059,12 +1075,12 @@ agent_turn() {
     local resp; resp=$(call_api "$payload_file")
     rm -f "$payload_file"
 
-    if [ -z "$resp" ]; then err "empty response from API (timeout or network?)"; rm -f "$tools_file"; return 1; fi
+    if [ -z "$resp" ]; then err "empty response from API (timeout or network?)"; rm -f "$tools_file" "$system_file"; return 1; fi
 
     local err_type; err_type=$(printf '%s' "$resp" | jq -r '.error.type // empty' 2>/dev/null)
     if [ -n "$err_type" ]; then
       err "API error: $err_type — $(printf '%s' "$resp" | jq -r '.error.message // "no message"')"
-      rm -f "$tools_file"
+      rm -f "$tools_file" "$system_file"
       return 1
     fi
 
@@ -1100,14 +1116,20 @@ agent_turn() {
       local result; result=$(execute_tool "$name" "$input_json")
       log_append '```'; log_append "$result"; log_append '```'
 
+      # Tool results can be large (read_file up to 250KB, ssh_exec up to
+      # 500 lines, etc.) — pass via tempfile, not --arg, to avoid Cygwin
+      # argv overflow.
+      local result_file; result_file=$(mktemp)
+      printf '%s' "$result" > "$result_file"
       results=$(printf '%s' "$results" | jq \
-        --arg id "$tu_id" --arg c "$result" \
+        --arg id "$tu_id" --rawfile c "$result_file" \
         '. + [{"type":"tool_result","tool_use_id":$id,"content":$c}]')
+      rm -f "$result_file"
     done < <(printf '%s' "$resp" | jq -c '.content[] | select(.type=="tool_use")')
 
     add_user_tool_results "$results"
   done
-  rm -f "$tools_file"
+  rm -f "$tools_file" "$system_file"
 }
 
 # ─────────────────────────────────────────────────────────────────────────────