diff --git a/.antigravity-plugin/hooks.json b/.antigravity-plugin/hooks.json
index 985cd89..d56d2ae 100644
--- a/.antigravity-plugin/hooks.json
+++ b/.antigravity-plugin/hooks.json
@@ -5,12 +5,12 @@
       {
         "type": "command",
         "command": "scripts\\run-powershell.cmd hooks\\ensure-monk-agent.ps1",
-        "timeout": 10
+        "timeout": 20
       },
       {
         "type": "command",
         "command": "./hooks/ensure-monk-agent.sh",
-        "timeout": 10
+        "timeout": 20
       }
     ]
   },
diff --git a/.antigravity-plugin/hooks/ensure-monk-agent.ps1 b/.antigravity-plugin/hooks/ensure-monk-agent.ps1
index ddc3c68..a5c7551 100644
--- a/.antigravity-plugin/hooks/ensure-monk-agent.ps1
+++ b/.antigravity-plugin/hooks/ensure-monk-agent.ps1
@@ -132,7 +132,8 @@ if ($Process) {
 # the health endpoint never responds, report an attempted start with a pointer
 # to the logs instead of a false "has been started".
 if ($Process -and -not $Process.HasExited) {
-  for ($i = 0; $i -lt 10; $i++) {
+  $ReadyDeadline = [DateTime]::UtcNow.AddSeconds(10)
+  while ([DateTime]::UtcNow -lt $ReadyDeadline) {
     Start-Sleep -Seconds 1
     if ($Process.HasExited) { break }
     if (Test-AgentRunning) {
diff --git a/.antigravity-plugin/hooks/ensure-monk-agent.sh b/.antigravity-plugin/hooks/ensure-monk-agent.sh
index 24463a7..87300ce 100755
--- a/.antigravity-plugin/hooks/ensure-monk-agent.sh
+++ b/.antigravity-plugin/hooks/ensure-monk-agent.sh
@@ -103,8 +103,8 @@ printf '%s\n' "$agent_pid" >"$pid_file"
 # Wait briefly for the agent to become reachable. If the process exits early or
 # the health endpoint never responds, report an attempted start with a pointer
 # to the logs instead of a false "has been started".
-i=0
-while [ "$i" -lt 10 ]; do
+ready_deadline=$(( $(date +%s) + 10 ))
+while [ "$(date +%s)" -lt "$ready_deadline" ]; do
   sleep 1
   if ! kill -0 "$agent_pid" 2>/dev/null; then
     break
@@ -113,7 +113,6 @@ while [ "$i" -lt 10 ]; do
     emit_inject_steps "monk-agent was not running and has been started. It may take a few seconds to initialize — use monk.install.status or monk.runtime.status to check readiness before issuing Monk operations."
     exit 0
   fi
-  i=$((i + 1))
 done
 
 emit_inject_steps "monk-agent was started but did not become ready within 10 seconds. Check monk.install.status or monk.runtime.status for details, or the launcher logs under $log_dir."
diff --git a/tests/antigravity-ensure-hook-timeout-budget.ps1 b/tests/antigravity-ensure-hook-timeout-budget.ps1
new file mode 100644
index 0000000..d1c44a7
--- /dev/null
+++ b/tests/antigravity-ensure-hook-timeout-budget.ps1
@@ -0,0 +1,108 @@
+$ErrorActionPreference = "Stop"
+
+$Repo = Split-Path -Parent (Split-Path -Parent $MyInvocation.MyCommand.Path)
+$Root = Join-Path ([IO.Path]::GetTempPath()) ("monk-antigravity-timeout-" + [guid]::NewGuid().ToString("N"))
+$AgentPath = Join-Path $Root "fake-agent.exe"
+$AgentSource = Join-Path $Root "fake-agent.cs"
+$EmptyInput = Join-Path $Root "stdin.txt"
+$StdoutPath = Join-Path $Root "hook.stdout.json"
+$StderrPath = Join-Path $Root "hook.stderr.log"
+$MonkHome = Join-Path $Root "monk-home"
+$PidFile = Join-Path $MonkHome "agent\launcher\run\monk-agent.pid"
+$EnvironmentNames = @(
+  "MONK_AGENT_PATH",
+  "MONK_AGENT_HOME",
+  "MONK_AGENT_PORT",
+  "MONK_DISABLE_ANALYTICS"
+)
+$OriginalEnvironment = @{}
+
+foreach ($Name in $EnvironmentNames) {
+  $OriginalEnvironment[$Name] = [Environment]::GetEnvironmentVariable($Name, "Process")
+}
+
+try {
+  New-Item -ItemType Directory -Force -Path $Root | Out-Null
+  New-Item -ItemType File -Force -Path $EmptyInput | Out-Null
+
+  @"
+using System;
+using System.Threading;
+class Program { static void Main(string[] args) { Thread.Sleep(TimeSpan.FromSeconds(60)); } }
+"@ | Set-Content $AgentSource
+
+  $Csc = Join-Path $env:WINDIR "Microsoft.NET\Framework64\v4.0.30319\csc.exe"
+  if (-not (Test-Path $Csc)) {
+    $Csc = Get-ChildItem "$env:WINDIR\Microsoft.NET\Framework64" -Filter csc.exe -Recurse |
+      Select-Object -First 1 -ExpandProperty FullName
+  }
+  if (-not $Csc) {
+    throw "csc.exe not found; cannot build the fake never-ready agent"
+  }
+
+  & $Csc /nologo /out:$AgentPath $AgentSource | Out-Null
+  if (-not (Test-Path $AgentPath)) {
+    throw "failed to compile fake-agent.exe"
+  }
+
+  $Hooks = Get-Content -Raw (Join-Path $Repo ".antigravity-plugin\hooks.json") | ConvertFrom-Json
+  $HostTimeoutSeconds = [int]$Hooks.'ensure-monk-agent'.PreInvocation[0].timeout
+  $HookPath = Join-Path $Repo ".antigravity-plugin\hooks\ensure-monk-agent.ps1"
+
+  $env:MONK_AGENT_PATH = $AgentPath
+  $env:MONK_AGENT_HOME = $MonkHome
+  $env:MONK_AGENT_PORT = "57420"
+  $env:MONK_DISABLE_ANALYTICS = "1"
+
+  # Force the native PowerShell hook and make each readiness probe consume its
+  # full two-second budget without touching the network.
+  $ChildCommand = @"
+`$ProgressPreference = 'SilentlyContinue'
+`$env:Path = `$PSHOME
+function global:Invoke-WebRequest {
+  Start-Sleep -Seconds 2
+  throw 'fixture: companion unavailable'
+}
+& '$HookPath'
+"@
+  $EncodedCommand = [Convert]::ToBase64String([Text.Encoding]::Unicode.GetBytes($ChildCommand))
+
+  $HookProcess = Start-Process `
+    -FilePath (Get-Process -Id $PID).Path `
+    -ArgumentList @("-NoLogo", "-NoProfile", "-NonInteractive", "-EncodedCommand", $EncodedCommand) `
+    -WindowStyle Hidden `
+    -RedirectStandardInput $EmptyInput `
+    -RedirectStandardOutput $StdoutPath `
+    -RedirectStandardError $StderrPath `
+    -PassThru
+
+  $Finished = $HookProcess.WaitForExit($HostTimeoutSeconds * 1000)
+  if (-not $Finished) {
+    Stop-Process -Id $HookProcess.Id -Force -ErrorAction SilentlyContinue
+    throw "Antigravity's declared $HostTimeoutSeconds-second timeout kills the native hook before it emits readiness JSON"
+  }
+  $HookProcess.WaitForExit()
+  $HookProcess.Refresh()
+
+  $Stdout = Get-Content -Raw $StdoutPath -ErrorAction SilentlyContinue
+  $Stderr = Get-Content -Raw $StderrPath -ErrorAction SilentlyContinue
+  if ($HookProcess.ExitCode -is [int] -and $HookProcess.ExitCode -ne 0) {
+    throw "native ensure hook exited $($HookProcess.ExitCode): $Stderr"
+  }
+  if ($Stdout -notmatch "did not become ready") {
+    throw "native ensure hook completed without the expected readiness diagnostic: $Stdout"
+  }
+
+  Write-Host "PASS: native Antigravity cold-start hook completes within its declared timeout"
+} finally {
+  if (Test-Path $PidFile) {
+    $AgentPid = Get-Content $PidFile -ErrorAction SilentlyContinue | Select-Object -First 1
+    if ($AgentPid) {
+      Stop-Process -Id $AgentPid -Force -ErrorAction SilentlyContinue
+    }
+  }
+  foreach ($Name in $EnvironmentNames) {
+    [Environment]::SetEnvironmentVariable($Name, $OriginalEnvironment[$Name], "Process")
+  }
+  Remove-Item -Recurse -Force $Root -ErrorAction SilentlyContinue
+}
diff --git a/tests/antigravity-ensure-hook-timeout-budget.sh b/tests/antigravity-ensure-hook-timeout-budget.sh
new file mode 100755
index 0000000..fd7ce22
--- /dev/null
+++ b/tests/antigravity-ensure-hook-timeout-budget.sh
@@ -0,0 +1,75 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+repo_root="$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)"
+hook="$repo_root/.antigravity-plugin/hooks/ensure-monk-agent.sh"
+hooks_json="$repo_root/.antigravity-plugin/hooks.json"
+
+tmp="$(mktemp -d)"
+agent_pid=""
+cleanup() {
+  if [ -f "$tmp/home/.monk/agent/launcher/run/monk-agent.pid" ]; then
+    agent_pid="$(cat "$tmp/home/.monk/agent/launcher/run/monk-agent.pid" 2>/dev/null || true)"
+  fi
+  if [ -n "$agent_pid" ]; then
+    kill "$agent_pid" 2>/dev/null || true
+  fi
+  rm -rf "$tmp"
+}
+trap cleanup EXIT
+
+mkdir -p "$tmp/bin" "$tmp/home"
+
+# Keep the launched process alive while making every readiness probe use its
+# full two-second request budget. This exposes the difference between retry
+# count and elapsed wall-clock time without using the network or monk-agent.
+cat >"$tmp/monk-agent" <<'EOF'
+#!/usr/bin/env sh
+exec sleep 60
+EOF
+chmod +x "$tmp/monk-agent"
+
+cat >"$tmp/bin/curl" <<'EOF'
+#!/usr/bin/env sh
+sleep 2
+exit 1
+EOF
+chmod +x "$tmp/bin/curl"
+
+configured_timeout="$(sed -n 's/.*"timeout"[[:space:]]*:[[:space:]]*\([0-9][0-9]*\).*/\1/p' "$hooks_json" | head -n 1)"
+if [ -z "$configured_timeout" ]; then
+  echo "fixture assumption failed: could not read Antigravity ensure hook timeout" >&2
+  exit 2
+fi
+
+set +e
+PATH="$tmp/bin:$PATH" \
+HOME="$tmp/home" \
+MONK_AGENT_PATH="$tmp/monk-agent" \
+MONK_AGENT_HOME="$tmp/home/.monk" \
+timeout "${configured_timeout}s" sh "$hook" </dev/null >"$tmp/stdout" 2>"$tmp/stderr"
+status=$?
+set -e
+
+if [ "$status" -eq 124 ]; then
+  if [ -s "$tmp/stdout" ]; then
+    echo "unexpected stdout before the host timeout:" >&2
+    cat "$tmp/stdout" >&2
+  fi
+  echo "FAIL: Antigravity's declared ${configured_timeout}-second timeout kills the cold-start hook before it emits readiness JSON" >&2
+  exit 1
+fi
+
+if [ "$status" -ne 0 ]; then
+  echo "FAIL: ensure hook exited with status $status" >&2
+  cat "$tmp/stderr" >&2
+  exit 1
+fi
+
+if ! grep -q 'did not become ready' "$tmp/stdout"; then
+  echo "FAIL: ensure hook completed without the expected readiness diagnostic" >&2
+  cat "$tmp/stdout" >&2
+  exit 1
+fi
+
+echo "PASS: Antigravity cold-start hook completes within its declared timeout"