diff --git a/.github/release-please.yml b/.github/release-please.yml
index 0418d39a20..15981814ce 100644
--- a/.github/release-please.yml
+++ b/.github/release-please.yml
@@ -2,4 +2,4 @@ primaryBranch: postgresql-dialect
 releaseType: java-yoshi
 bumpMinorPreMajor: true
 handleGHRelease: true
-extraFiles: ["README.md", "samples/java/jdbc/README.md"]
+extraFiles: ["README.md", "samples/java/jdbc/README.md", "spanner-pg-connector/README.md"]
diff --git a/README.md b/README.md
index e3186f9606..81fb4eb86a 100644
--- a/README.md
+++ b/README.md
@@ -188,6 +188,20 @@ class PGProxyRunner {
 See [samples/java/jdbc](samples/java/jdbc) for a small sample application that adds
 PGAdapter as a compile-time dependency and runs it together with the main application.
 
+### Spanner PG Connector (`spgc`)
+
+`spanner-pg-connector` (aliased as `spgc`) is a CLI tool designed to make working with existing
+PostgreSQL command-line tools (such as `psql` or `pg_dump`) against Spanner
+easier. It bundles PGAdapter and a minimal Java runtime—so you do not need Java or Docker installed
+locally—and automatically starts and stops PGAdapter in the background when running your tool.
+
+```shell
+spgc psql -d "projects/my-project/instances/my-instance/databases/my-database"
+```
+
+See [spanner-pg-connector/README.md](spanner-pg-connector/README.md) for installation instructions,
+authentication, environment variables, and more examples.
+
 ## Emulator
 A pre-built Docker image that contains both PGAdapter and the Spanner Emulator can be started with
 these commands:
diff --git a/spanner-pg-connector/README.md b/spanner-pg-connector/README.md
new file mode 100644
index 0000000000..8042e2e366
--- /dev/null
+++ b/spanner-pg-connector/README.md
@@ -0,0 +1,137 @@
+# Spanner PG Connector (`spgc`)
+
+`spanner-pg-connector` (aliased as `spgc`) is a CLI tool designed to make working with existing
+PostgreSQL command-line tools (such as `psql` or `pg_dump`) against Spanner
+easier. It bundles PGAdapter and a minimal Java runtime—so you do not need Java or Docker installed
+locally—and automatically starts PGAdapter in the background on a dynamically assigned localhost
+port, configures the standard PostgreSQL environment variables (`PGHOST` and `PGPORT`), runs your
+PostgreSQL tool against it, and stops PGAdapter when the tool exits.
+
+The PostgreSQL client tool itself (for example `psql`) is not bundled and must be installed and
+available on your `PATH`.
+
+## Installation
+
+### Linux (`x86_64`) and macOS (`aarch64` / `x86_64`)
+
+```shell
+curl -fsSL https://raw.githubusercontent.com/GoogleCloudPlatform/pgadapter/postgresql-dialect/spanner-pg-connector/install.sh | sh
+```
+
+### Windows (`x86_64`, PowerShell)
+
+```powershell
+irm https://raw.githubusercontent.com/GoogleCloudPlatform/pgadapter/postgresql-dialect/spanner-pg-connector/install.ps1 | iex
+```
+
+By default, the installer downloads the latest release into `~/.spanner-pg-connector` and adds it
+to your `PATH`. You can customize the installation with `VERSION` and `INSTALL_DIR`:
+
+<!--- {x-version-update-start:google-cloud-spanner-pgadapter:released} -->
+```shell
+curl -fsSL https://raw.githubusercontent.com/GoogleCloudPlatform/pgadapter/postgresql-dialect/spanner-pg-connector/install.sh \
+  | VERSION=v0.55.3 INSTALL_DIR="$HOME/.spanner-pg-connector" sh
+```
+
+```powershell
+$env:VERSION = "v0.55.3"; $env:INSTALL_DIR = "$HOME\.spanner-pg-connector"; irm https://raw.githubusercontent.com/GoogleCloudPlatform/pgadapter/postgresql-dialect/spanner-pg-connector/install.ps1 | iex
+```
+<!--- {x-version-update-end} -->
+
+### Manual Installation (Without the Installer Script)
+
+You can also download and extract the release archive directly and add the extracted directory to
+your `PATH` (both `spanner-pg-connector` and `spgc` are included in the archive):
+
+#### Linux and macOS
+
+<!--- {x-version-update-start:google-cloud-spanner-pgadapter:released} -->
+```shell
+VERSION=v0.55.3
+PLATFORM=linux-x64 # linux-x64, mac-aarch64, or mac-x64
+mkdir -p ~/.spanner-pg-connector
+curl -fsSL "https://artifactregistry.googleapis.com/v1/projects/cloud-spanner-pg-adapter/locations/us/repositories/spanner-pg-connector/files/spanner-pg-connector:${VERSION}:spanner-pg-connector-${PLATFORM}.tar.gz:download?alt=media" \
+  | tar -xz -C ~/.spanner-pg-connector
+export PATH="$HOME/.spanner-pg-connector:$PATH"
+```
+<!--- {x-version-update-end} -->
+
+#### Windows (PowerShell)
+
+<!--- {x-version-update-start:google-cloud-spanner-pgadapter:released} -->
+```powershell
+$Version = "v0.55.3"
+$InstallDir = Join-Path $HOME ".spanner-pg-connector"
+$ZipPath = Join-Path $env:TEMP "spanner-pg-connector-windows-x64.zip"
+New-Item -ItemType Directory -Path $InstallDir -Force | Out-Null
+Invoke-RestMethod -Uri "https://artifactregistry.googleapis.com/v1/projects/cloud-spanner-pg-adapter/locations/us/repositories/spanner-pg-connector/files/spanner-pg-connector:${Version}:spanner-pg-connector-windows-x64.zip:download?alt=media" -OutFile $ZipPath
+Expand-Archive -Path $ZipPath -DestinationPath $InstallDir -Force
+$env:PATH = "$env:PATH;$InstallDir"
+```
+<!--- {x-version-update-end} -->
+
+To make the `PATH` change persistent across new terminal sessions, add it to your shell profile
+(for example `~/.bashrc` or `~/.zshrc` on Linux/macOS) or your user `Path` environment variable on
+Windows.
+
+Verify the installation by checking the version:
+
+```shell
+spgc --version
+```
+
+## Authentication
+
+`spgc` does not require a PostgreSQL username or password between the client tool and the local
+PGAdapter proxy. To authenticate with Spanner, `spgc` uses Google Cloud
+**Application Default Credentials (ADC)** in the following order:
+
+1. **`GOOGLE_APPLICATION_CREDENTIALS` environment variable**: Pointing to a service account key or
+   credentials JSON file.
+2. **User credentials via `gcloud`**: Set up by running:
+   ```shell
+   gcloud auth application-default login
+   ```
+3. **Attached service account**: Used automatically when running on Google Cloud environments such
+   as Compute Engine, Cloud Shell, Cloud Workstations, Cloud Run, or GKE Workload Identity.
+
+When connecting to the Spanner Emulator (`SPANNER_EMULATOR_HOST`), authentication is not
+required and is disabled automatically.
+
+## Usage
+
+Pass the client command and its arguments directly to `spgc` (or `spanner-pg-connector`):
+
+```shell
+spgc psql -d "projects/my-project/instances/my-instance/databases/my-database"
+```
+
+You can also run `spgc --help` to view usage details or `spgc --version` to print the bundled
+PGAdapter version.
+
+### Environment Variables
+
+You can configure the project, instance, default database, or Spanner Emulator via
+environment variables:
+
+* `GOOGLE_CLOUD_PROJECT`: Google Cloud project ID.
+* `SPANNER_INSTANCE`: Spanner instance ID.
+* `SPANNER_DATABASE`: Default Spanner database ID (used if the command does not specify `-d`, `--dbname`, or `--database`).
+* `SPANNER_EMULATOR_HOST`: If set, connects to the Spanner Emulator at `host:port` (for example `localhost:9010`) instead of Spanner. Must be unset when connecting to Spanner.
+* `GOOGLE_APPLICATION_CREDENTIALS`: Optional path to a Google Cloud credentials JSON file.
+
+### Examples
+
+```shell
+export GOOGLE_CLOUD_PROJECT=my-project
+export SPANNER_INSTANCE=my-instance
+
+# Start an interactive psql session
+spgc psql -d my-database
+
+# Run a single query
+spgc psql -d my-database -c "SELECT 1"
+
+# Connect to the Spanner Emulator
+SPANNER_EMULATOR_HOST=localhost:9010 spgc psql -d test-database
+```
diff --git a/spanner-pg-connector/install.ps1 b/spanner-pg-connector/install.ps1
index d13072ed48..1a37531de1 100644
--- a/spanner-pg-connector/install.ps1
+++ b/spanner-pg-connector/install.ps1
@@ -16,7 +16,7 @@
 # PowerShell script to install Spanner PG Connector on Windows
 
 $Project = if ($env:PROJECT_ID) { $env:PROJECT_ID } else { "cloud-spanner-pg-adapter" }
-$Location = if ($env:AR_LOCATION) { $env:AR_LOCATION } else { "us-central1" }
+$Location = if ($env:AR_LOCATION) { $env:AR_LOCATION } else { "us" }
 $Repository = if ($env:AR_REPOSITORY) { $env:AR_REPOSITORY } else { "spanner-pg-connector" }
 $Package = "spanner-pg-connector"
 $Version = $env:VERSION
@@ -76,7 +76,7 @@ New-Item -ItemType Directory -Path $StagingDir -Force | Out-Null
 try {
     # 2. Download package
     Write-Host "Downloading package from Artifact Registry..."
-    $DownloadUrl = "https://artifactregistry.googleapis.com/v1/projects/$Project/locations/$Location/repositories/$Repository/files/spanner-pg-connector:$Version:spanner-pg-connector-windows-x64.zip:download?alt=media"
+    $DownloadUrl = "https://artifactregistry.googleapis.com/v1/projects/$Project/locations/$Location/repositories/$Repository/files/spanner-pg-connector:${Version}:spanner-pg-connector-windows-x64.zip:download?alt=media"
 
     $DownloadSuccess = $false
     try {
diff --git a/spanner-pg-connector/install.sh b/spanner-pg-connector/install.sh
index 51afc89df0..6ecfbc33e4 100755
--- a/spanner-pg-connector/install.sh
+++ b/spanner-pg-connector/install.sh
@@ -21,7 +21,7 @@ set -e
 # Configuration (Supports env overrides)
 VERSION="${VERSION:-}"
 PROJECT_ID="${PROJECT_ID:-cloud-spanner-pg-adapter}"
-AR_LOCATION="${AR_LOCATION:-us-central1}"
+AR_LOCATION="${AR_LOCATION:-us}"
 AR_REPOSITORY="${AR_REPOSITORY:-spanner-pg-connector}"
 INSTALL_DIR="${INSTALL_DIR:-${HOME}/.spanner-pg-connector}"