diff --git a/.antigravity-plugin/scripts/uninstall-monk-agent.ps1 b/.antigravity-plugin/scripts/uninstall-monk-agent.ps1
index 22fcd38..38d8c52 100644
--- a/.antigravity-plugin/scripts/uninstall-monk-agent.ps1
+++ b/.antigravity-plugin/scripts/uninstall-monk-agent.ps1
@@ -29,6 +29,9 @@ $AgentDataDir = Join-Path $MonkHome "agent"
 $PidFile = Join-Path $AgentDataDir "launcher\run\monk-agent.pid"
 $Target = Join-Path $InstallDir "monk-agent.exe"
 $Checksum = Join-Path $InstallDir "monk-agent.sha256"
+$AntigravityMcpConfig = if ($env:MONK_ANTIGRAVITY_CONFIG) { $env:MONK_ANTIGRAVITY_CONFIG } else {
+  Join-Path $HOME ".gemini\config\mcp_config.json"
+}
 
 if (-not $Yes) {
   $suffix = if ($Runtime) { " and Monk runtime" } else { "" }
@@ -135,10 +138,53 @@ fi
   wsl.exe -d $distro --user root -- sh -lc $script
 }
 
+function Remove-AntigravityMcpRegistration {
+  if (-not (Test-Path -LiteralPath $AntigravityMcpConfig -PathType Leaf)) {
+    return
+  }
+
+  try {
+    $Config = Get-Content -LiteralPath $AntigravityMcpConfig -Raw | ConvertFrom-Json
+  } catch {
+    Write-Warning "Leaving malformed Antigravity MCP config unchanged: $AntigravityMcpConfig"
+    return
+  }
+
+  if ($null -eq $Config) {
+    return
+  }
+  $ServersProperty = $Config.PSObject.Properties["mcpServers"]
+  if ($null -eq $ServersProperty -or $null -eq $ServersProperty.Value) {
+    return
+  }
+  $MonkProperty = $ServersProperty.Value.PSObject.Properties["monk"]
+  if ($null -eq $MonkProperty) {
+    return
+  }
+
+  $ServersProperty.Value.PSObject.Properties.Remove("monk")
+  if (@($ServersProperty.Value.PSObject.Properties).Count -eq 0) {
+    $Config.PSObject.Properties.Remove("mcpServers")
+  }
+
+  $Directory = Split-Path -Parent $AntigravityMcpConfig
+  $TempPath = Join-Path $Directory (".monk-mcp-config-{0}.tmp" -f [guid]::NewGuid())
+  try {
+    $Json = $Config | ConvertTo-Json -Depth 100
+    [IO.File]::WriteAllText($TempPath, $Json + [Environment]::NewLine, [Text.UTF8Encoding]::new($false))
+    Move-Item -LiteralPath $TempPath -Destination $AntigravityMcpConfig -Force
+    Write-Host "Removed Monk MCP registration from $AntigravityMcpConfig"
+  } catch {
+    Remove-Item -LiteralPath $TempPath -Force -ErrorAction SilentlyContinue
+    Write-Warning "Could not update Antigravity MCP config: $AntigravityMcpConfig"
+  }
+}
+
 Stop-ManagedAgent
 Remove-AgentFiles
 if ($Runtime) {
   Remove-MonkRuntime
 }
+Remove-AntigravityMcpRegistration
 
 Write-Host "monk-agent uninstall complete."
diff --git a/.antigravity-plugin/scripts/uninstall-monk-agent.sh b/.antigravity-plugin/scripts/uninstall-monk-agent.sh
index ae4fe76..deafb15 100755
--- a/.antigravity-plugin/scripts/uninstall-monk-agent.sh
+++ b/.antigravity-plugin/scripts/uninstall-monk-agent.sh
@@ -156,10 +156,78 @@ remove_runtime() {
   esac
 }
 
+remove_antigravity_mcp_registration() {
+  mcp_cfg="${MONK_ANTIGRAVITY_CONFIG:-"$home_dir/.gemini/config/mcp_config.json"}"
+  [ -f "$mcp_cfg" ] || return 0
+
+  tmp="$(mktemp "${TMPDIR:-/tmp}/monk-mcp-config.XXXXXX")"
+  if command -v jq >/dev/null 2>&1; then
+    if ! jq empty "$mcp_cfg" >/dev/null 2>&1; then
+      rm -f "$tmp"
+      echo "Warning: leaving malformed Antigravity MCP config unchanged: $mcp_cfg" >&2
+      return 0
+    fi
+    if ! jq -e '.mcpServers | type == "object" and has("monk")' "$mcp_cfg" >/dev/null 2>&1; then
+      rm -f "$tmp"
+      return 0
+    fi
+    if ! jq 'del(.mcpServers.monk) | if .mcpServers == {} then del(.mcpServers) else . end' "$mcp_cfg" >"$tmp"; then
+      rm -f "$tmp"
+      echo "Warning: could not update Antigravity MCP config: $mcp_cfg" >&2
+      return 0
+    fi
+  elif command -v python3 >/dev/null 2>&1; then
+    status=0
+    python3 - "$mcp_cfg" >"$tmp" <<'PY' || status=$?
+import json
+import sys
+
+path = sys.argv[1]
+try:
+    with open(path, encoding="utf-8-sig") as source:
+        config = json.load(source)
+except (OSError, ValueError):
+    sys.exit(2)
+
+servers = config.get("mcpServers") if isinstance(config, dict) else None
+if not isinstance(servers, dict) or "monk" not in servers:
+    sys.exit(3)
+
+del servers["monk"]
+if not servers:
+    del config["mcpServers"]
+json.dump(config, sys.stdout, indent=2)
+sys.stdout.write("\n")
+PY
+    case "$status" in
+      0) ;;
+      3) rm -f "$tmp"; return 0 ;;
+      *)
+        rm -f "$tmp"
+        echo "Warning: leaving malformed Antigravity MCP config unchanged: $mcp_cfg" >&2
+        return 0
+        ;;
+    esac
+  else
+    rm -f "$tmp"
+    echo "Warning: could not inspect $mcp_cfg; remove mcpServers.monk manually (jq or python3 required)." >&2
+    return 0
+  fi
+
+  if mv "$tmp" "$mcp_cfg"; then
+    echo "Removed Monk MCP registration from $mcp_cfg" >&2
+  else
+    rm -f "$tmp"
+    echo "Warning: could not update Antigravity MCP config: $mcp_cfg" >&2
+  fi
+}
+
 stop_agent
 remove_agent_files
 if [ "$remove_runtime" = "1" ]; then
   remove_runtime
 fi
 
+remove_antigravity_mcp_registration
+
 echo "monk-agent uninstall complete."
diff --git a/.github/workflows/install-e2e.yml b/.github/workflows/install-e2e.yml
index 880b41e..f61a55f 100644
--- a/.github/workflows/install-e2e.yml
+++ b/.github/workflows/install-e2e.yml
@@ -27,6 +27,10 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v6
 
+      - name: Test POSIX Antigravity MCP cleanup
+        shell: bash
+        run: ./tests/uninstall-antigravity-mcp.sh
+
       - name: Install monk-agent
         shell: bash
         env:
@@ -66,6 +70,10 @@ jobs:
         shell: pwsh
         run: .\tests\block-monk-windows.ps1
 
+      - name: Test Windows Antigravity MCP cleanup
+        shell: pwsh
+        run: .\tests\uninstall-antigravity-mcp-windows.ps1
+
       - name: Install monk-agent
         shell: pwsh
         env:
diff --git a/plugins/monk/scripts/uninstall-monk-agent.ps1 b/plugins/monk/scripts/uninstall-monk-agent.ps1
index 22fcd38..38d8c52 100644
--- a/plugins/monk/scripts/uninstall-monk-agent.ps1
+++ b/plugins/monk/scripts/uninstall-monk-agent.ps1
@@ -29,6 +29,9 @@ $AgentDataDir = Join-Path $MonkHome "agent"
 $PidFile = Join-Path $AgentDataDir "launcher\run\monk-agent.pid"
 $Target = Join-Path $InstallDir "monk-agent.exe"
 $Checksum = Join-Path $InstallDir "monk-agent.sha256"
+$AntigravityMcpConfig = if ($env:MONK_ANTIGRAVITY_CONFIG) { $env:MONK_ANTIGRAVITY_CONFIG } else {
+  Join-Path $HOME ".gemini\config\mcp_config.json"
+}
 
 if (-not $Yes) {
   $suffix = if ($Runtime) { " and Monk runtime" } else { "" }
@@ -135,10 +138,53 @@ fi
   wsl.exe -d $distro --user root -- sh -lc $script
 }
 
+function Remove-AntigravityMcpRegistration {
+  if (-not (Test-Path -LiteralPath $AntigravityMcpConfig -PathType Leaf)) {
+    return
+  }
+
+  try {
+    $Config = Get-Content -LiteralPath $AntigravityMcpConfig -Raw | ConvertFrom-Json
+  } catch {
+    Write-Warning "Leaving malformed Antigravity MCP config unchanged: $AntigravityMcpConfig"
+    return
+  }
+
+  if ($null -eq $Config) {
+    return
+  }
+  $ServersProperty = $Config.PSObject.Properties["mcpServers"]
+  if ($null -eq $ServersProperty -or $null -eq $ServersProperty.Value) {
+    return
+  }
+  $MonkProperty = $ServersProperty.Value.PSObject.Properties["monk"]
+  if ($null -eq $MonkProperty) {
+    return
+  }
+
+  $ServersProperty.Value.PSObject.Properties.Remove("monk")
+  if (@($ServersProperty.Value.PSObject.Properties).Count -eq 0) {
+    $Config.PSObject.Properties.Remove("mcpServers")
+  }
+
+  $Directory = Split-Path -Parent $AntigravityMcpConfig
+  $TempPath = Join-Path $Directory (".monk-mcp-config-{0}.tmp" -f [guid]::NewGuid())
+  try {
+    $Json = $Config | ConvertTo-Json -Depth 100
+    [IO.File]::WriteAllText($TempPath, $Json + [Environment]::NewLine, [Text.UTF8Encoding]::new($false))
+    Move-Item -LiteralPath $TempPath -Destination $AntigravityMcpConfig -Force
+    Write-Host "Removed Monk MCP registration from $AntigravityMcpConfig"
+  } catch {
+    Remove-Item -LiteralPath $TempPath -Force -ErrorAction SilentlyContinue
+    Write-Warning "Could not update Antigravity MCP config: $AntigravityMcpConfig"
+  }
+}
+
 Stop-ManagedAgent
 Remove-AgentFiles
 if ($Runtime) {
   Remove-MonkRuntime
 }
+Remove-AntigravityMcpRegistration
 
 Write-Host "monk-agent uninstall complete."
diff --git a/plugins/monk/scripts/uninstall-monk-agent.sh b/plugins/monk/scripts/uninstall-monk-agent.sh
index ae4fe76..deafb15 100755
--- a/plugins/monk/scripts/uninstall-monk-agent.sh
+++ b/plugins/monk/scripts/uninstall-monk-agent.sh
@@ -156,10 +156,78 @@ remove_runtime() {
   esac
 }
 
+remove_antigravity_mcp_registration() {
+  mcp_cfg="${MONK_ANTIGRAVITY_CONFIG:-"$home_dir/.gemini/config/mcp_config.json"}"
+  [ -f "$mcp_cfg" ] || return 0
+
+  tmp="$(mktemp "${TMPDIR:-/tmp}/monk-mcp-config.XXXXXX")"
+  if command -v jq >/dev/null 2>&1; then
+    if ! jq empty "$mcp_cfg" >/dev/null 2>&1; then
+      rm -f "$tmp"
+      echo "Warning: leaving malformed Antigravity MCP config unchanged: $mcp_cfg" >&2
+      return 0
+    fi
+    if ! jq -e '.mcpServers | type == "object" and has("monk")' "$mcp_cfg" >/dev/null 2>&1; then
+      rm -f "$tmp"
+      return 0
+    fi
+    if ! jq 'del(.mcpServers.monk) | if .mcpServers == {} then del(.mcpServers) else . end' "$mcp_cfg" >"$tmp"; then
+      rm -f "$tmp"
+      echo "Warning: could not update Antigravity MCP config: $mcp_cfg" >&2
+      return 0
+    fi
+  elif command -v python3 >/dev/null 2>&1; then
+    status=0
+    python3 - "$mcp_cfg" >"$tmp" <<'PY' || status=$?
+import json
+import sys
+
+path = sys.argv[1]
+try:
+    with open(path, encoding="utf-8-sig") as source:
+        config = json.load(source)
+except (OSError, ValueError):
+    sys.exit(2)
+
+servers = config.get("mcpServers") if isinstance(config, dict) else None
+if not isinstance(servers, dict) or "monk" not in servers:
+    sys.exit(3)
+
+del servers["monk"]
+if not servers:
+    del config["mcpServers"]
+json.dump(config, sys.stdout, indent=2)
+sys.stdout.write("\n")
+PY
+    case "$status" in
+      0) ;;
+      3) rm -f "$tmp"; return 0 ;;
+      *)
+        rm -f "$tmp"
+        echo "Warning: leaving malformed Antigravity MCP config unchanged: $mcp_cfg" >&2
+        return 0
+        ;;
+    esac
+  else
+    rm -f "$tmp"
+    echo "Warning: could not inspect $mcp_cfg; remove mcpServers.monk manually (jq or python3 required)." >&2
+    return 0
+  fi
+
+  if mv "$tmp" "$mcp_cfg"; then
+    echo "Removed Monk MCP registration from $mcp_cfg" >&2
+  else
+    rm -f "$tmp"
+    echo "Warning: could not update Antigravity MCP config: $mcp_cfg" >&2
+  fi
+}
+
 stop_agent
 remove_agent_files
 if [ "$remove_runtime" = "1" ]; then
   remove_runtime
 fi
 
+remove_antigravity_mcp_registration
+
 echo "monk-agent uninstall complete."
diff --git a/scripts/uninstall-monk-agent.ps1 b/scripts/uninstall-monk-agent.ps1
index 22fcd38..38d8c52 100644
--- a/scripts/uninstall-monk-agent.ps1
+++ b/scripts/uninstall-monk-agent.ps1
@@ -29,6 +29,9 @@ $AgentDataDir = Join-Path $MonkHome "agent"
 $PidFile = Join-Path $AgentDataDir "launcher\run\monk-agent.pid"
 $Target = Join-Path $InstallDir "monk-agent.exe"
 $Checksum = Join-Path $InstallDir "monk-agent.sha256"
+$AntigravityMcpConfig = if ($env:MONK_ANTIGRAVITY_CONFIG) { $env:MONK_ANTIGRAVITY_CONFIG } else {
+  Join-Path $HOME ".gemini\config\mcp_config.json"
+}
 
 if (-not $Yes) {
   $suffix = if ($Runtime) { " and Monk runtime" } else { "" }
@@ -135,10 +138,53 @@ fi
   wsl.exe -d $distro --user root -- sh -lc $script
 }
 
+function Remove-AntigravityMcpRegistration {
+  if (-not (Test-Path -LiteralPath $AntigravityMcpConfig -PathType Leaf)) {
+    return
+  }
+
+  try {
+    $Config = Get-Content -LiteralPath $AntigravityMcpConfig -Raw | ConvertFrom-Json
+  } catch {
+    Write-Warning "Leaving malformed Antigravity MCP config unchanged: $AntigravityMcpConfig"
+    return
+  }
+
+  if ($null -eq $Config) {
+    return
+  }
+  $ServersProperty = $Config.PSObject.Properties["mcpServers"]
+  if ($null -eq $ServersProperty -or $null -eq $ServersProperty.Value) {
+    return
+  }
+  $MonkProperty = $ServersProperty.Value.PSObject.Properties["monk"]
+  if ($null -eq $MonkProperty) {
+    return
+  }
+
+  $ServersProperty.Value.PSObject.Properties.Remove("monk")
+  if (@($ServersProperty.Value.PSObject.Properties).Count -eq 0) {
+    $Config.PSObject.Properties.Remove("mcpServers")
+  }
+
+  $Directory = Split-Path -Parent $AntigravityMcpConfig
+  $TempPath = Join-Path $Directory (".monk-mcp-config-{0}.tmp" -f [guid]::NewGuid())
+  try {
+    $Json = $Config | ConvertTo-Json -Depth 100
+    [IO.File]::WriteAllText($TempPath, $Json + [Environment]::NewLine, [Text.UTF8Encoding]::new($false))
+    Move-Item -LiteralPath $TempPath -Destination $AntigravityMcpConfig -Force
+    Write-Host "Removed Monk MCP registration from $AntigravityMcpConfig"
+  } catch {
+    Remove-Item -LiteralPath $TempPath -Force -ErrorAction SilentlyContinue
+    Write-Warning "Could not update Antigravity MCP config: $AntigravityMcpConfig"
+  }
+}
+
 Stop-ManagedAgent
 Remove-AgentFiles
 if ($Runtime) {
   Remove-MonkRuntime
 }
+Remove-AntigravityMcpRegistration
 
 Write-Host "monk-agent uninstall complete."
diff --git a/scripts/uninstall-monk-agent.sh b/scripts/uninstall-monk-agent.sh
index ae4fe76..deafb15 100755
--- a/scripts/uninstall-monk-agent.sh
+++ b/scripts/uninstall-monk-agent.sh
@@ -156,10 +156,78 @@ remove_runtime() {
   esac
 }
 
+remove_antigravity_mcp_registration() {
+  mcp_cfg="${MONK_ANTIGRAVITY_CONFIG:-"$home_dir/.gemini/config/mcp_config.json"}"
+  [ -f "$mcp_cfg" ] || return 0
+
+  tmp="$(mktemp "${TMPDIR:-/tmp}/monk-mcp-config.XXXXXX")"
+  if command -v jq >/dev/null 2>&1; then
+    if ! jq empty "$mcp_cfg" >/dev/null 2>&1; then
+      rm -f "$tmp"
+      echo "Warning: leaving malformed Antigravity MCP config unchanged: $mcp_cfg" >&2
+      return 0
+    fi
+    if ! jq -e '.mcpServers | type == "object" and has("monk")' "$mcp_cfg" >/dev/null 2>&1; then
+      rm -f "$tmp"
+      return 0
+    fi
+    if ! jq 'del(.mcpServers.monk) | if .mcpServers == {} then del(.mcpServers) else . end' "$mcp_cfg" >"$tmp"; then
+      rm -f "$tmp"
+      echo "Warning: could not update Antigravity MCP config: $mcp_cfg" >&2
+      return 0
+    fi
+  elif command -v python3 >/dev/null 2>&1; then
+    status=0
+    python3 - "$mcp_cfg" >"$tmp" <<'PY' || status=$?
+import json
+import sys
+
+path = sys.argv[1]
+try:
+    with open(path, encoding="utf-8-sig") as source:
+        config = json.load(source)
+except (OSError, ValueError):
+    sys.exit(2)
+
+servers = config.get("mcpServers") if isinstance(config, dict) else None
+if not isinstance(servers, dict) or "monk" not in servers:
+    sys.exit(3)
+
+del servers["monk"]
+if not servers:
+    del config["mcpServers"]
+json.dump(config, sys.stdout, indent=2)
+sys.stdout.write("\n")
+PY
+    case "$status" in
+      0) ;;
+      3) rm -f "$tmp"; return 0 ;;
+      *)
+        rm -f "$tmp"
+        echo "Warning: leaving malformed Antigravity MCP config unchanged: $mcp_cfg" >&2
+        return 0
+        ;;
+    esac
+  else
+    rm -f "$tmp"
+    echo "Warning: could not inspect $mcp_cfg; remove mcpServers.monk manually (jq or python3 required)." >&2
+    return 0
+  fi
+
+  if mv "$tmp" "$mcp_cfg"; then
+    echo "Removed Monk MCP registration from $mcp_cfg" >&2
+  else
+    rm -f "$tmp"
+    echo "Warning: could not update Antigravity MCP config: $mcp_cfg" >&2
+  fi
+}
+
 stop_agent
 remove_agent_files
 if [ "$remove_runtime" = "1" ]; then
   remove_runtime
 fi
 
+remove_antigravity_mcp_registration
+
 echo "monk-agent uninstall complete."
diff --git a/tests/uninstall-antigravity-mcp-windows.ps1 b/tests/uninstall-antigravity-mcp-windows.ps1
new file mode 100644
index 0000000..f9010f8
--- /dev/null
+++ b/tests/uninstall-antigravity-mcp-windows.ps1
@@ -0,0 +1,91 @@
+param(
+  [string]$RepoRoot = (Split-Path -Parent $PSScriptRoot)
+)
+
+$ErrorActionPreference = "Stop"
+$WindowsPowerShell = Join-Path $env:SystemRoot "System32\WindowsPowerShell\v1.0\powershell.exe"
+$TempRoot = Join-Path $env:TEMP "monk-uninstall-mcp-$PID"
+$PreviousInstallDir = $env:MONK_AGENT_INSTALL_DIR
+$PreviousMonkHome = $env:MONK_AGENT_HOME
+$PreviousConfig = $env:MONK_ANTIGRAVITY_CONFIG
+
+$Scripts = @(
+  (Join-Path $RepoRoot "scripts\uninstall-monk-agent.ps1"),
+  (Join-Path $RepoRoot "plugins\monk\scripts\uninstall-monk-agent.ps1"),
+  (Join-Path $RepoRoot ".antigravity-plugin\scripts\uninstall-monk-agent.ps1")
+)
+
+function Invoke-IsolatedUninstall {
+  param(
+    [string]$Script,
+    [string]$Name,
+    [string]$ConfigText
+  )
+
+  $CaseRoot = Join-Path $TempRoot $Name
+  $ConfigPath = Join-Path $CaseRoot "config\mcp_config.json"
+  New-Item -ItemType Directory -Force -Path (Split-Path -Parent $ConfigPath) | Out-Null
+  [IO.File]::WriteAllText($ConfigPath, $ConfigText, [Text.UTF8Encoding]::new($false))
+
+  $env:MONK_AGENT_INSTALL_DIR = Join-Path $CaseRoot "install"
+  $env:MONK_AGENT_HOME = Join-Path $CaseRoot "monk-home"
+  $env:MONK_ANTIGRAVITY_CONFIG = $ConfigPath
+  New-Item -ItemType Directory -Force -Path $env:MONK_AGENT_INSTALL_DIR, $env:MONK_AGENT_HOME | Out-Null
+
+  & $WindowsPowerShell -NoProfile -ExecutionPolicy Bypass -File $Script -Yes -KeepData | Out-Null
+  if ($LASTEXITCODE -ne 0) {
+    throw "Uninstaller failed for $Name with exit code $LASTEXITCODE"
+  }
+  return $ConfigPath
+}
+
+try {
+  for ($Index = 0; $Index -lt $Scripts.Count; $Index++) {
+    $ConfigPath = Invoke-IsolatedUninstall -Script $Scripts[$Index] -Name "copy-$Index" -ConfigText @'
+{
+  "theme": "dark",
+  "mcpServers": {
+    "existing": { "serverUrl": "http://127.0.0.1:9000/mcp" },
+    "monk": { "serverUrl": "http://127.0.0.1:7419/mcp" }
+  }
+}
+'@
+    $Config = Get-Content -Raw -LiteralPath $ConfigPath | ConvertFrom-Json
+    if ($Config.theme -ne "dark") {
+      throw "Uninstaller changed an unrelated top-level value for copy $Index"
+    }
+    if ($null -eq $Config.mcpServers.existing) {
+      throw "Uninstaller removed an unrelated MCP server for copy $Index"
+    }
+    if ($null -ne $Config.mcpServers.PSObject.Properties["monk"]) {
+      throw "Uninstaller left the Monk MCP registration for copy $Index"
+    }
+  }
+
+  $EmptyConfigPath = Invoke-IsolatedUninstall -Script $Scripts[0] -Name "empty-servers" -ConfigText '{"other":true,"mcpServers":{"monk":{"serverUrl":"http://127.0.0.1:7419/mcp"}}}'
+  $EmptyConfig = Get-Content -Raw -LiteralPath $EmptyConfigPath | ConvertFrom-Json
+  if ($null -ne $EmptyConfig.PSObject.Properties["mcpServers"] -or -not $EmptyConfig.other) {
+    throw "Uninstaller did not remove the empty mcpServers object cleanly"
+  }
+
+  $Malformed = '{not-json'
+  $MalformedPath = Invoke-IsolatedUninstall -Script $Scripts[0] -Name "malformed" -ConfigText $Malformed
+  if ((Get-Content -Raw -LiteralPath $MalformedPath) -cne $Malformed) {
+    throw "Uninstaller changed malformed JSON"
+  }
+
+  $Reference = (Get-Content -Raw -LiteralPath $Scripts[0]) -replace "`r`n", "`n"
+  foreach ($Script in $Scripts[1..2]) {
+    $Copy = (Get-Content -Raw -LiteralPath $Script) -replace "`r`n", "`n"
+    if ($Copy -cne $Reference) {
+      throw "Rendered PowerShell uninstaller differs: $Script"
+    }
+  }
+} finally {
+  $env:MONK_AGENT_INSTALL_DIR = $PreviousInstallDir
+  $env:MONK_AGENT_HOME = $PreviousMonkHome
+  $env:MONK_ANTIGRAVITY_CONFIG = $PreviousConfig
+  Remove-Item -LiteralPath $TempRoot -Recurse -Force -ErrorAction SilentlyContinue
+}
+
+Write-Host "Windows Antigravity MCP uninstall tests passed."
diff --git a/tests/uninstall-antigravity-mcp.sh b/tests/uninstall-antigravity-mcp.sh
new file mode 100755
index 0000000..f67e806
--- /dev/null
+++ b/tests/uninstall-antigravity-mcp.sh
@@ -0,0 +1,82 @@
+#!/usr/bin/env sh
+set -eu
+
+repo_root="${1:-$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)}"
+root="$(mktemp -d)"
+trap 'rm -rf "$root"' EXIT HUP INT TERM
+
+scripts="
+$repo_root/scripts/uninstall-monk-agent.sh
+$repo_root/plugins/monk/scripts/uninstall-monk-agent.sh
+$repo_root/.antigravity-plugin/scripts/uninstall-monk-agent.sh
+"
+
+index=0
+printf '%s\n' "$scripts" | while IFS= read -r script; do
+  [ -n "$script" ] || continue
+  case_root="$root/copy-$index"
+  config="$case_root/config/mcp_config.json"
+  mkdir -p "$(dirname "$config")" "$case_root/install" "$case_root/monk-home"
+  cat >"$config" <<'JSON'
+{
+  "theme": "dark",
+  "mcpServers": {
+    "existing": { "serverUrl": "http://127.0.0.1:9000/mcp" },
+    "monk": { "serverUrl": "http://127.0.0.1:7419/mcp" }
+  }
+}
+JSON
+
+  HOME="$case_root/home" \
+    MONK_AGENT_INSTALL_DIR="$case_root/install" \
+    MONK_AGENT_HOME="$case_root/monk-home" \
+    MONK_ANTIGRAVITY_CONFIG="$config" \
+    "$script" --yes --keep-data >/dev/null
+
+  python3 - "$config" <<'PY'
+import json
+import sys
+
+with open(sys.argv[1], encoding="utf-8") as source:
+    config = json.load(source)
+assert config["theme"] == "dark"
+assert config["mcpServers"]["existing"]["serverUrl"] == "http://127.0.0.1:9000/mcp"
+assert "monk" not in config["mcpServers"]
+PY
+  index=$((index + 1))
+done
+
+case_root="$root/empty-servers"
+config="$case_root/config/mcp_config.json"
+mkdir -p "$(dirname "$config")" "$case_root/install" "$case_root/monk-home"
+printf '%s\n' '{"other":true,"mcpServers":{"monk":{"serverUrl":"http://127.0.0.1:7419/mcp"}}}' >"$config"
+HOME="$case_root/home" \
+  MONK_AGENT_INSTALL_DIR="$case_root/install" \
+  MONK_AGENT_HOME="$case_root/monk-home" \
+  MONK_ANTIGRAVITY_CONFIG="$config" \
+  "$repo_root/scripts/uninstall-monk-agent.sh" --yes --keep-data >/dev/null
+python3 - "$config" <<'PY'
+import json
+import sys
+
+with open(sys.argv[1], encoding="utf-8") as source:
+    config = json.load(source)
+assert config == {"other": True}
+PY
+
+case_root="$root/malformed"
+config="$case_root/config/mcp_config.json"
+mkdir -p "$(dirname "$config")" "$case_root/install" "$case_root/monk-home"
+printf '%s' '{not-json' >"$config"
+cp "$config" "$config.before"
+HOME="$case_root/home" \
+  MONK_AGENT_INSTALL_DIR="$case_root/install" \
+  MONK_AGENT_HOME="$case_root/monk-home" \
+  MONK_ANTIGRAVITY_CONFIG="$config" \
+  "$repo_root/scripts/uninstall-monk-agent.sh" --yes --keep-data >/dev/null
+cmp "$config.before" "$config"
+
+cmp "$repo_root/scripts/uninstall-monk-agent.sh" "$repo_root/plugins/monk/scripts/uninstall-monk-agent.sh"
+cmp "$repo_root/scripts/uninstall-monk-agent.sh" "$repo_root/.antigravity-plugin/scripts/uninstall-monk-agent.sh"
+
+echo "POSIX Antigravity MCP uninstall tests passed."