diff --git a/.gitignore b/.gitignore
index 1023ed2..d2b3ff0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,4 @@
-/pyml-validator
-/pyml-validator.yml
+/sites-yml-validator
 
 .DS_Store
 
diff --git a/.goreleaser.yml b/.goreleaser.yml
index b679fd3..f3edd14 100644
--- a/.goreleaser.yml
+++ b/.goreleaser.yml
@@ -1,5 +1,5 @@
 ---
-project_name: pyml-validator
+project_name: sites-yml-validator
 
 before:
   hooks:
diff --git a/Makefile b/Makefile
index 6092ce8..c7afa4e 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-APP := pyml-validator
+APP := sites-yml-validator
 
 include devops/make/common.mk
 include devops/make/common-go.mk
diff --git a/README.MD b/README.MD
index 2263207..8b244e8 100644
--- a/README.MD
+++ b/README.MD
@@ -1,46 +1,65 @@
 # Pantheon YML Validator
 
-A utility for validating a sites.yml file on a Pantheon site during WordPress multisites' search-replace tasks. Asprirationally to include pantheon.yml validation in the future.
+[![Early Access](https://img.shields.io/badge/Pantheon-Early_Access-yellow?logo=pantheon&color=FFDC28)](https://docs.pantheon.io/oss-support-levels#early-access)
+
+A utility for validating a `sites.yml` file on a Pantheon site during a WordPress multisite's search and replace tasks. For more information, see [Pantheon's Multisite Docs](https://docs.pantheon.io/guides/multisite/search-replace/).
 
 ## Usage
 
-### Sites.yml
+### sites.yml
+To validate the `sites.yml` file, run:
 ```
-$ pyml-validator sites path/to/sites.yml
+$ sites-yml-validator sites path/to/sites.yml
 ```
 
-See [this annotated fixture](./fixtures/sites/valid.yml) for an example of a valid sites.yml file.
+#### Valid File Example
+See [this annotated fixture](./fixtures/sites/valid.yml) for an example of a valid `sites.yml` file.
+
+The basic format for the file is:
+``` yml
+api_version: 1
+domain_maps:
+  {env_name}:
+    {blog_id}: {site_url}
+```
+A `sites.yml` file is valid if:
+- the `api_version` is `1`
+- the key for each item in `domain_maps` is a valid Pantheon environment name (`dev`, `test`, `multidev`, etc.)
+- For each subsite listed for an environment:
+   - the key is an integer
+   - the value is a valid Pantheon hostname
+- there are no more than 25 subsites listed for any environment
 
 ## Install
 
-### [Download the latest binary](https://github.com/pantheon-systems/pyml-validator/releases/latest)
+### [Download the latest binary](https://github.com/pantheon-systems/sites-yml-validator/releases/latest)
 
 Use wget to download, gzipped pre-compiled binaries:
-For instance, VERSION=v0.0.11 and BINARY=pyml-validator_linux_amd64
+For instance, VERSION=v0.0.11 and BINARY=sites-yml-validator_linux_amd64
 
 ### Compressed via tar.gz
 ```bash
-wget https://github.com/pantheon-systems/pyml-validator/releases/download/${VERSION}/${BINARY}.tar.gz -O - |\
-  tar xz && mv ${BINARY} /usr/bin/pyml-validator
+wget https://github.com/pantheon-systems/sites-yml-validator/releases/download/${VERSION}/${BINARY}.tar.gz -O - |\
+  tar xz && mv ${BINARY} /usr/bin/sites-yml-validator
 ```
 
 ### Plain binary
 
 ```bash
-wget https://github.com/pantheon-systems/pyml-validator/releases/download/${VERSION}/${BINARY} -O /usr/bin/pyml-validator &&\
-    chmod +x /usr/bin/pyml-validator
+wget https://github.com/pantheon-systems/sites-yml-validator/releases/download/${VERSION}/${BINARY} -O /usr/bin/sites-yml-validator &&\
+    chmod +x /usr/bin/sites-yml-validator
 ```
 
 ### Latest version
 
 ```bash
-wget https://github.com/pantheon-systems/pyml-validator/releases/latest/download/pyml-validator_linux_amd64 -O /usr/bin/pyml-validator &&\
-    chmod +x /usr/bin/pyml-validator
+wget https://github.com/pantheon-systems/sites-yml-validator/releases/latest/download/sites-yml-validator_linux_amd64 -O /usr/bin/sites-yml-validator &&\
+    chmod +x /usr/bin/sites-yml-validator
 ```
 
 ## Testing
 
-[![Coverage Status](https://coveralls.io/repos/github/pantheon-systems/pyml-validator/badge.svg?t=PGhafd)](https://coveralls.io/github/pantheon-systems/pyml-validator)
+[![Coverage Status](https://coveralls.io/repos/github/pantheon-systems/sites-yml-validator/badge.svg?t=PGhafd)](https://coveralls.io/github/pantheon-systems/sites-yml-validator)
 
 `make test` runs linting and testing.
 
diff --git a/cmd/root.go b/cmd/root.go
index 9cb7ed3..a0e54d2 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -9,9 +9,9 @@ import (
 var FilePath string
 
 var rootCmd = &cobra.Command{
-	Use:   "pyml-validator",
-	Short: "Pyml-validator validates sites.yml",
-	Long: `Pyml-validator is a validator for sites.yml, used for WPMS search-replace.
+	Use:   "sites-yml-validator",
+	Short: "sites-yml-validator validates sites.yml",
+	Long: `sites-yml-validator is a validator for sites.yml, used for WPMS search-replace.
 Ensures that the given config file can be used by the platform.`,
 }
 
diff --git a/cmd/validators.go b/cmd/validators.go
index 9c3a95e..93cc628 100644
--- a/cmd/validators.go
+++ b/cmd/validators.go
@@ -2,7 +2,7 @@ package cmd
 
 import (
 	"fmt"
-	"pyml-validator/pkg/validator"
+	"sites-yml-validator/pkg/validator"
 
 	"github.com/spf13/cobra"
 )
diff --git a/fixtures/sites/valid.yml b/fixtures/sites/valid.yml
index cf95d51..2d8cade 100644
--- a/fixtures/sites/valid.yml
+++ b/fixtures/sites/valid.yml
@@ -29,19 +29,9 @@ domain_maps:
     4: staff-portal.searchreplacetest.com
     5: customers.searchreplacetest.com
     6: hr-department.searchreplacetest.com
-  autopilot:
-    1: autopilot-srtest.pantheonsite.io
-    2: about.autopilot-srtest.pantheonsite.io
-    5: customers.autopilot-srtest.pantheonsite.io
-    6: hr-department.autopilot-srtest.pantheonsite.io
-  nomatch:
-    31: jobs.nomatch-srtest.pantheonsite.io
-    32: legal.nomatch-srtest.pantheonsite.io
-  domains:
-    1: searchreplace.com
-    2: about-searchreplace.com
-    3: employee-resources-searchreplace.com
-    4: staff-portal-searchreplace.com
-    5: customers-searchreplace.com
-    6: hr-department-searchreplace.com
+  mdevname:
+    1: mdevname-srtest.pantheonsite.io
+    2: about.mdevname-srtest.pantheonsite.io
+    5: customers.mdevname-srtest.pantheonsite.io
+    6: hr-department.mdevname-srtest.pantheonsite.io
 # Anything else in the file will be ignored, but not rejected.
\ No newline at end of file
diff --git a/go.mod b/go.mod
index de5a42d..dba3385 100644
--- a/go.mod
+++ b/go.mod
@@ -1,4 +1,4 @@
-module pyml-validator
+module sites-yml-validator
 
 go 1.20
 
diff --git a/main.go b/main.go
index 68348e0..a43ea28 100644
--- a/main.go
+++ b/main.go
@@ -1,6 +1,6 @@
 package main
 
-import "pyml-validator/cmd"
+import "sites-yml-validator/cmd"
 
 func main() {
 	cmd.Execute()
diff --git a/pkg/model/sites.go b/pkg/model/sites.go
index 01856c4..5d147e6 100644
--- a/pkg/model/sites.go
+++ b/pkg/model/sites.go
@@ -6,7 +6,8 @@ type SitesYml struct {
 	DomainMaps DomainMaps `yaml:"domain_maps"`
 }
 
+// DomainMaps is a collection of blog ID/blog domains keyed by environment name.
 type DomainMaps map[string]DomainMapByEnvironment
 
-// DomainMapByEnvironment is a map of site (blog) domains keyed by blog ID.
+// DomainMapByEnvironment is a collection of site (blog) domains keyed by blog ID.
 type DomainMapByEnvironment map[int]string
diff --git a/pkg/validator/sites.go b/pkg/validator/sites.go
index 17153bb..b3bb2f2 100644
--- a/pkg/validator/sites.go
+++ b/pkg/validator/sites.go
@@ -3,8 +3,8 @@ package validator
 import (
 	"fmt"
 	"os"
-	"pyml-validator/pkg/model"
 	"regexp"
+	"sites-yml-validator/pkg/model"
 
 	"gopkg.in/yaml.v3"
 )
diff --git a/pkg/validator/sites_test.go b/pkg/validator/sites_test.go
index 9b0304a..763e9b5 100644
--- a/pkg/validator/sites_test.go
+++ b/pkg/validator/sites_test.go
@@ -3,7 +3,7 @@ package validator
 import (
 	"errors"
 	"fmt"
-	"pyml-validator/pkg/model"
+	"sites-yml-validator/pkg/model"
 	"strings"
 	"testing"