diff --git a/.github/workflows/cli-ci.yml b/.github/workflows/cli-ci.yml
index b59a821d036..fcb9fcd038c 100644
--- a/.github/workflows/cli-ci.yml
+++ b/.github/workflows/cli-ci.yml
@@ -32,7 +32,8 @@ jobs:
           node-version: "20"
       - run: npm install -g cspell@8.13.1
       - name: Spell check for go and docs
-        run: cspell lint '**/*.{go,md}' --config ./cli/azd/.vscode/cspell.yaml --root ./cli/azd --no-progress
+        working-directory: cli/azd
+        run: cspell lint '**/*.go' '**/*.md' --exclude 'extensions/**' --config ./.vscode/cspell.yaml --no-progress
 
   Copyright-check:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/cspell-ext.yml b/.github/workflows/cspell-ext.yml
new file mode 100644
index 00000000000..d436f538c04
--- /dev/null
+++ b/.github/workflows/cspell-ext.yml
@@ -0,0 +1,35 @@
+name: cspell-ext
+
+on:
+  pull_request:
+    paths:
+      - "cli/azd/extensions/**/*.go"
+      - "cli/azd/extensions/**/*.md"
+      - "cli/azd/extensions/**/cspell.yaml"
+      - "cli/azd/.vscode/cspell.yaml"
+      - "cli/azd/.vscode/cspell-azd-dictionary.txt"
+      - ".github/workflows/cspell-ext.yml"
+    branches: [main]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+
+jobs:
+  cspell-lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: "20"
+      - run: npm install -g cspell@8.13.1
+      - name: Spell check for extensions
+        working-directory: cli/azd
+        # Each extension has its own cspell.yaml that imports the main config.
+        # cspell's config cascade auto-discovers per-extension configs for files
+        # under each extension directory, applying extension-specific overrides.
+        run: cspell lint 'extensions/**/*.go' 'extensions/**/*.md' --config ./.vscode/cspell.yaml --no-progress
diff --git a/cli/azd/.vscode/cspell.yaml b/cli/azd/.vscode/cspell.yaml
index ed554c08502..8e55ec6519f 100644
--- a/cli/azd/.vscode/cspell.yaml
+++ b/cli/azd/.vscode/cspell.yaml
@@ -262,11 +262,6 @@ overrides:
       - println
       - myext
       - Fatalf
-  - filename: extensions/microsoft.azd.ai.builder/internal/cmd/start.go
-    words:
-      - dall
-      - datasource
-      - vectorizing
   - filename: pkg/project/dockerfile_builder.go
     words:
       - WORKDIR
@@ -312,12 +307,6 @@ overrides:
   - filename: pkg/extensions/manager.go
     words:
       - myext
-  - filename: extensions/microsoft.azd.extensions/internal/resources/languages/**/.gitignore
-    words:
-      - rsuser
-      - userosscache
-      - docstates
-      - dylib
   - filename: docs/recording-functional-tests-guide.md
     words:
       - httptest
@@ -353,21 +342,12 @@ overrides:
     words:
       - WORKDIR
       - workdir
-  - filename: extensions/microsoft.azd.demo/internal/cmd/metadata.go
-    words:
-      - invopop
-  - filename: extensions/microsoft.azd.concurx/internal/cmd/prompt_model.go
-    words:
-      - textinput
   - filename: pkg/azdext/scope_detector.go
     words:
       - fakeazure
   - filename: "{pkg/azapi/permissions.go,pkg/infra/provisioning/bicep/bicep_provider.go}"
     words:
       - ABAC
-  - filename: extensions/azure.ai.models/internal/cmd/custom_create.go
-    words:
-      - Qwen
   - filename: pkg/infra/provisioning/bicep/local_preflight.go
     words:
       - actioned
diff --git a/cli/azd/extensions/azure.ai.agents/cspell.yaml b/cli/azd/extensions/azure.ai.agents/cspell.yaml
index 05b17854c91..9d286f5f537 100644
--- a/cli/azd/extensions/azure.ai.agents/cspell.yaml
+++ b/cli/azd/extensions/azure.ai.agents/cspell.yaml
@@ -1,3 +1,4 @@
+import: ../../.vscode/cspell.yaml
 words:
   # Azure region names
   - australiaeast
diff --git a/cli/azd/extensions/azure.ai.finetune/cspell.yaml b/cli/azd/extensions/azure.ai.finetune/cspell.yaml
index 6f2423ef132..5b0b92be211 100644
--- a/cli/azd/extensions/azure.ai.finetune/cspell.yaml
+++ b/cli/azd/extensions/azure.ai.finetune/cspell.yaml
@@ -1,3 +1,4 @@
+import: ../../.vscode/cspell.yaml
 words:
   - azureprovider
   - finetune
diff --git a/cli/azd/extensions/azure.ai.models/cspell.yaml b/cli/azd/extensions/azure.ai.models/cspell.yaml
index 99b5b35a7ac..593b7fc23e9 100644
--- a/cli/azd/extensions/azure.ai.models/cspell.yaml
+++ b/cli/azd/extensions/azure.ai.models/cspell.yaml
@@ -1,3 +1,8 @@
+import: ../../.vscode/cspell.yaml
+overrides:
+  - filename: internal/cmd/custom_create.go
+    words:
+      - Qwen
 words:
   - azcopy
   - Kimi
diff --git a/cli/azd/extensions/azure.appservice/cspell.yaml b/cli/azd/extensions/azure.appservice/cspell.yaml
new file mode 100644
index 00000000000..a01eaa9fab4
--- /dev/null
+++ b/cli/azd/extensions/azure.appservice/cspell.yaml
@@ -0,0 +1 @@
+import: ../../.vscode/cspell.yaml
diff --git a/cli/azd/extensions/azure.coding-agent/cspell.yaml b/cli/azd/extensions/azure.coding-agent/cspell.yaml
new file mode 100644
index 00000000000..a01eaa9fab4
--- /dev/null
+++ b/cli/azd/extensions/azure.coding-agent/cspell.yaml
@@ -0,0 +1 @@
+import: ../../.vscode/cspell.yaml
diff --git a/cli/azd/extensions/microsoft.azd.ai.builder/cspell.yaml b/cli/azd/extensions/microsoft.azd.ai.builder/cspell.yaml
new file mode 100644
index 00000000000..c0c295bd5ca
--- /dev/null
+++ b/cli/azd/extensions/microsoft.azd.ai.builder/cspell.yaml
@@ -0,0 +1,7 @@
+import: ../../.vscode/cspell.yaml
+overrides:
+  - filename: internal/cmd/start.go
+    words:
+      - dall
+      - datasource
+      - vectorizing
diff --git a/cli/azd/extensions/microsoft.azd.concurx/cspell.yaml b/cli/azd/extensions/microsoft.azd.concurx/cspell.yaml
new file mode 100644
index 00000000000..5b94b868a3b
--- /dev/null
+++ b/cli/azd/extensions/microsoft.azd.concurx/cspell.yaml
@@ -0,0 +1,5 @@
+import: ../../.vscode/cspell.yaml
+overrides:
+  - filename: internal/cmd/prompt_model.go
+    words:
+      - textinput
diff --git a/cli/azd/extensions/microsoft.azd.demo/cspell.yaml b/cli/azd/extensions/microsoft.azd.demo/cspell.yaml
index a182b3e72c5..349efcbc745 100644
--- a/cli/azd/extensions/microsoft.azd.demo/cspell.yaml
+++ b/cli/azd/extensions/microsoft.azd.demo/cspell.yaml
@@ -1,2 +1,7 @@
+import: ../../.vscode/cspell.yaml
+overrides:
+  - filename: internal/cmd/metadata.go
+    words:
+      - invopop
 words:
   - colours
diff --git a/cli/azd/extensions/microsoft.azd.extensions/cspell.yaml b/cli/azd/extensions/microsoft.azd.extensions/cspell.yaml
new file mode 100644
index 00000000000..bf8aa741d07
--- /dev/null
+++ b/cli/azd/extensions/microsoft.azd.extensions/cspell.yaml
@@ -0,0 +1,8 @@
+import: ../../.vscode/cspell.yaml
+overrides:
+  - filename: internal/resources/languages/**/.gitignore
+    words:
+      - rsuser
+      - userosscache
+      - docstates
+      - dylib