diff --git a/docs/schema/plugins.json b/docs/schema/plugins.json
index f0d49fa0b..a99caecd3 100644
--- a/docs/schema/plugins.json
+++ b/docs/schema/plugins.json
@@ -40,6 +40,9 @@
         {
           "$ref": "plugins/privacy.json"
         },
+        {
+          "$ref": "plugins/projects.json"
+        },
         {
           "$ref": "plugins/search.json"
         },
diff --git a/docs/schema/plugins/optimize.json b/docs/schema/plugins/optimize.json
index 44ef537f9..c7c80c44d 100644
--- a/docs/schema/plugins/optimize.json
+++ b/docs/schema/plugins/optimize.json
@@ -24,8 +24,7 @@
             "concurrency": {
               "title": "Concurrency (number of CPUs)",
               "markdownDescription": "https://squidfunk.github.io/mkdocs-material/setup/building-an-optimized-site/#+optimize.concurrency",
-              "type": "number",
-              "default": 1
+              "type": "number"
             },
             "cache": {
               "title": "Enable caching",
diff --git a/docs/schema/plugins/privacy.json b/docs/schema/plugins/privacy.json
index aaa36b830..b5483e52e 100644
--- a/docs/schema/plugins/privacy.json
+++ b/docs/schema/plugins/privacy.json
@@ -24,8 +24,7 @@
             "concurrency": {
               "title": "Concurrency (number of CPUs)",
               "markdownDescription": "https://squidfunk.github.io/mkdocs-material/setup/ensuring-data-privacy/#+privacy.concurrency",
-              "type": "number",
-              "default": 1
+              "type": "number"
             },
             "assets": {
               "title": "Process external assets",
diff --git a/docs/schema/plugins/projects.json b/docs/schema/plugins/projects.json
new file mode 100644
index 000000000..c5e5b6ce8
--- /dev/null
+++ b/docs/schema/plugins/projects.json
@@ -0,0 +1,48 @@
+{
+  "$schema": "https://json-schema.org/draft-07/schema",
+  "title": "Built-in projects plugin",
+  "oneOf": [
+    {
+      "markdownDescription": "https://squidfunk.github.io/mkdocs-material/setup/building-an-optimized-site/#built-in-projects-plugin",
+      "enum": [
+        "projects"
+      ]
+    },
+    {
+      "type": "object",
+      "properties": {
+        "projects": {
+          "markdownDescription": "https://squidfunk.github.io/mkdocs-material/setup/building-an-optimized-site/#built-in-projects-plugin",
+          "type": "object",
+          "properties": {
+            "enabled": {
+              "title": "Enable plugin",
+              "markdownDescription": "https://squidfunk.github.io/mkdocs-material/setup/building-an-optimized-site/#+projects.enabled",
+              "type": "boolean",
+              "default": true
+            },
+            "concurrency": {
+              "title": "Concurrency (number of CPUs)",
+              "markdownDescription": "https://squidfunk.github.io/mkdocs-material/setup/building-an-optimized-site/#+projects.concurrency",
+              "type": "number"
+            },
+            "projects": {
+              "title": "Enable projects",
+              "markdownDescription": "https://squidfunk.github.io/mkdocs-material/setup/building-an-optimized-site/#+projects.projects",
+              "type": "boolean",
+              "default": true
+            },
+            "projects_dir": {
+              "title": "Projects directory",
+              "markdownDescription": "https://squidfunk.github.io/mkdocs-material/setup/building-an-optimized-site/#+projects.projects_dir",
+              "type": "string",
+              "default": "projects"
+            }
+          },
+          "additionalProperties": false
+        }
+      },
+      "additionalProperties": false
+    }
+  ]
+}
diff --git a/docs/schema/plugins/social.json b/docs/schema/plugins/social.json
index b2ba2e29a..678ea580b 100644
--- a/docs/schema/plugins/social.json
+++ b/docs/schema/plugins/social.json
@@ -24,8 +24,7 @@
             "concurrency": {
               "title": "Concurrency (number of CPUs)",
               "markdownDescription": "https://squidfunk.github.io/mkdocs-material/setup/setting-up-social-cards/#+social.concurrency",
-              "type": "number",
-              "default": 1
+              "type": "number"
             },
             "cards": {
               "title": "Social cards",