diff --git a/package.json b/package.json
index 644e1db..7e233a6 100644
--- a/package.json
+++ b/package.json
@@ -35,7 +35,7 @@
   "devDependencies": {
     "@architect/eslint-config": "^2.1.2",
     "dotenv": "^16.3.1",
-    "eslint": "^8.54.0",
+    "eslint": "^8.56.0",
     "tap-arc": "^1.2.2",
     "tape": "^5.7.2"
   },
diff --git a/src/index.cjs b/src/index.cjs
index 686fef1..439ea0a 100644
--- a/src/index.cjs
+++ b/src/index.cjs
@@ -69,6 +69,7 @@ module.exports = {
      * @param {BaseParams & {domain: string}} options
      */
     async add ({ token, domain, _staging }) {
+      if (!domain) throw Error('missing_domain')
       return write({ token, _staging, scope: 'domains' }, { domain })
     },
 
@@ -86,6 +87,7 @@ module.exports = {
      * @param {BaseParams & {domain: string}} options
      */
     async check ({ token, domain, _staging }) {
+      if (!domain) throw Error('missing_domain')
       return read({ token, _staging, scope: 'domains', path: domain, })
     },
 
@@ -97,7 +99,6 @@ module.exports = {
       if (!appID) throw Error('missing_appID')
       if (!envID) throw Error('missing_envID')
       if (!domainID) throw Error('missing_domainID')
-
       return write(
         { token, _staging, scope: 'domains', path: `${domainID}/link` },
         { appID, envID },
@@ -109,14 +110,26 @@ module.exports = {
      * @param {BaseParams & {domainID: string, appID?: string, envID?: string}} options
      */
     async unlink ({ token, domainID, appID, envID, _staging }) {
+      if (!appID) throw Error('missing_appID')
+      if (!envID) throw Error('missing_envID')
       if (!domainID) throw Error('missing_domainID')
-
       return write(
         { token, _staging, scope: 'domains', path: `${domainID}/unlink` },
         { appID, envID },
       )
     },
 
+    /**
+     * @description validate an external domain
+     * repeat this operation until the domain is validated
+     * @param {BaseParams & {domainID: string}} options
+     * returns DNS validation records
+     */
+    async validate ({ token, domainID, _staging }) {
+      if (!domainID) throw Error('missing_domainID')
+      return write({ token, _staging, scope: 'domains', path: `${domainID}/validate` })
+    },
+
     records: {
       /**
        * @description list domain records
@@ -136,6 +149,7 @@ module.exports = {
        */
       async upsert ({ token, domainID, changes, _staging }) {
         if (!domainID) throw Error('missing_domainID')
+        if (!changes) throw Error('missing_changes')
         return write(
           { token, _staging, scope: 'domains', path: `${domainID}/records` },
           { changes },
@@ -152,6 +166,7 @@ module.exports = {
        */
       async delete ({ token, domainID, record, _staging }) {
         if (!domainID) throw Error('missing_domainID')
+        if (!record) throw Error('missing_record')
         return write(
           { token, _staging, scope: 'domains', path: `${domainID}/records/delete` },
           { ...record },
diff --git a/test/domains-test.mjs b/test/domains-test.mjs
index 49a0d51..ec680a6 100644
--- a/test/domains-test.mjs
+++ b/test/domains-test.mjs
@@ -7,13 +7,16 @@ e.config()
 const token = process.env.ACCESS_TOKEN || '123'
 
 test('begin', t => {
-  t.plan(10)
+  t.plan(13)
   t.ok(begin, 'begin')
   t.ok(begin.domains, 'begin.domains')
   t.ok(begin.domains.list, 'begin.domains.list')
+  t.ok(begin.domains.add, 'begin.domains.add')
+  t.ok(begin.domains.remove, 'begin.domains.remove')
   t.ok(begin.domains.check, 'begin.domains.check')
   t.ok(begin.domains.link, 'begin.domains.link')
   t.ok(begin.domains.unlink, 'begin.domains.unlink')
+  t.ok(begin.domains.validate, 'begin.domains.validate')
   t.ok(begin.domains.records, 'begin.domains.records')
   t.ok(begin.domains.records.list, 'begin.domains.records.list')
   t.ok(begin.domains.records.upsert, 'begin.domains.records.upsert')