New route to check blacklist only

api/openapi.yaml

@@ -202,6 +202,39 @@ paths:
               schema:
                 $ref: '#/components/schemas/Error'
 
+  /blacklist:
+    post:
+      tags:
+        - tests
+      summary: Check an IP address against DNS blacklists
+      description: Tests a single IP address (IPv4 or IPv6) against configured DNS-based blacklists (RBLs) without requiring an actual email to be sent. Returns results immediately.
+      operationId: checkBlacklist
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/BlacklistCheckRequest'
+      responses:
+        '200':
+          description: Blacklist check completed successfully
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/BlacklistCheckResponse'
+        '400':
+          description: Invalid request
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Error'
+        '500':
+          description: Internal server error
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Error'
+
   /status:
     get:
       tags:
@@ -1182,3 +1215,48 @@ components:
           example: "A"
         dns_results:
           $ref: '#/components/schemas/DNSResults'
+
+    BlacklistCheckRequest:
+      type: object
+      required:
+        - ip
+      properties:
+        ip:
+          type: string
+          description: IPv4 or IPv6 address to check against blacklists
+          example: "192.0.2.1"
+          pattern: '^([0-9]{1,3}\.){3}[0-9]{1,3}$|^([0-9a-fA-F]{0,4}:){7}[0-9a-fA-F]{0,4}$|^::([0-9a-fA-F]{0,4}:){0,6}[0-9a-fA-F]{0,4}$|^([0-9a-fA-F]{0,4}:){1,6}:([0-9a-fA-F]{0,4}:){0,5}[0-9a-fA-F]{0,4}$'
+
+    BlacklistCheckResponse:
+      type: object
+      required:
+        - ip
+        - checks
+        - listed_count
+        - score
+        - grade
+      properties:
+        ip:
+          type: string
+          description: The IP address that was checked
+          example: "192.0.2.1"
+        checks:
+          type: array
+          items:
+            $ref: '#/components/schemas/BlacklistCheck'
+          description: List of blacklist check results
+        listed_count:
+          type: integer
+          description: Number of blacklists that have this IP listed
+          example: 0
+        score:
+          type: integer
+          minimum: 0
+          maximum: 100
+          description: Blacklist score (0-100, higher is better)
+          example: 100
+        grade:
+          type: string
+          enum: [A+, A, B, C, D, E, F]
+          description: Letter grade representation of the score
+          example: "A+"