Adds support to outputschema

Signed-off-by: Marcos Candeia <[email protected]>

Author: mcandeia

README.md

@@ -60,8 +60,9 @@ export default defineConfig({
 ```
 
 ## Configuration
-Add the MCP server as a SSE endpoint using the production domain: https://sites-mcp.decocdn.com/mcp/sse
 
+Add the MCP server as a SSE endpoint using the production domain:
+https://sites-mcp.decocdn.com/mcp/sse
 
 <img width="1718" alt="image" src="https://github.com/user-attachments/assets/8a94dd3b-be41-48b5-98db-22ddae16391f" />
 

deno.json

@@ -1,6 +1,6 @@
 {
   "name": "@deco/mcp",
-  "version": "0.1.9",
+  "version": "0.1.10",
   "exports": "./mod.ts",
   "tasks": {
     "check": "deno fmt && deno lint && deno check mod.ts"

mcp/server.ts

@@ -47,6 +47,12 @@ export interface Options<TManifest extends AppManifest> {
   include?: Array<keyof (TManifest["actions"] & TManifest["loaders"])>;
   exclude?: Array<keyof (TManifest["actions"] & TManifest["loaders"])>;
 }
+
+interface RootSchema extends JSONSchema7 {
+  inputSchema?: string;
+  outputSchema?: string;
+}
+
 function registerTools<TManifest extends AppManifest>(
   mcp: McpServer,
   deco: Deco<TManifest>,
@@ -73,7 +79,7 @@ function registerTools<TManifest extends AppManifest>(
 
     const tools = [...availableLoaders, ...availableActions].map(
       (func) => {
-        func = func as JSONSchema7;
+        func = func as RootSchema;
         if (!func.$ref || func.$ref === RESOLVABLE_DEFINITION) return;
         const funcDefinition = schemas.definitions[idFromDefinition(func.$ref)];
         const resolveType =
@@ -94,9 +100,17 @@ function registerTools<TManifest extends AppManifest>(
           )
         ) return;
 
-        const props = funcDefinition.allOf ?? [];
-        const propsSchema = props[0];
-        const ref = (propsSchema as JSONSchema7)?.$ref;
+        const getInputSchemaId = () => {
+          if ("inputSchema" in func) {
+            return func.inputSchema as string;
+          }
+          const props = funcDefinition.allOf ?? [];
+          const propsSchema = props[0];
+          const ref = (propsSchema as JSONSchema7)?.$ref;
+          return ref;
+        };
+
+        const ref = getInputSchemaId();
         const rawInputSchema = ref
           ? schemas.definitions[idFromDefinition(ref)]
           : undefined;
@@ -109,6 +123,23 @@ function registerTools<TManifest extends AppManifest>(
           )
           : undefined;
 
+        const outputSchemaId = "outputSchema" in func
+          ? func.outputSchema as string
+          : undefined;
+
+        const rawOutputSchema = outputSchemaId
+          ? schemas.definitions[idFromDefinition(outputSchemaId)]
+          : undefined;
+
+        const selfReference = (rawOutputSchema?.anyOf ?? [])[0];
+
+        const outputSchema = selfReference
+          ? dereferenceSchema(
+            selfReference as JSONSchema7,
+            schemas.definitions,
+          )
+          : undefined;
+
         // Handle tool name slugification and clashes
         let toolName = (funcDefinition as { name?: string })?.name ??
           (inputSchema as { name?: string })?.name ?? slugify(resolveType);
@@ -122,17 +153,21 @@ function registerTools<TManifest extends AppManifest>(
         }
         toolNames.set(toolName, resolveType);
 
+        const normalizeSchema = (schema?: JSONSchema7) => {
+          return schema && "type" in schema && schema.type === "object"
+            ? schema
+            : {
+              type: "object",
+              additionalProperties: true,
+            };
+        };
         return {
           name: toolName,
+          resolveType,
           description: funcDefinition.description ?? inputSchema?.description ??
             resolveType,
-          inputSchema: inputSchema && "type" in inputSchema &&
-              inputSchema.type === "object"
-            ? inputSchema
-            : {
-              type: "object",
-              properties: {},
-            },
+          outputSchema: normalizeSchema(outputSchema),
+          inputSchema: normalizeSchema(inputSchema),
         };
       },
     );

mcp/utils.ts

@@ -1,3 +1,4 @@
+// deno-lint-ignore-file no-explicit-any
 import type { JSONSchema7 } from "@deco/deco";
 
 export function dereferenceSchema(
@@ -27,7 +28,7 @@ export function dereferenceSchema(
 
   // Handle allOf
   if (result.allOf) {
-    result.allOf = result.allOf.map((subSchema) =>
+    result.allOf = result.allOf.map((subSchema: any) =>
       dereferenceSchema(
         subSchema as JSONSchema7,
         definitions,
@@ -38,7 +39,7 @@ export function dereferenceSchema(
 
   // Handle anyOf
   if (result.anyOf) {
-    result.anyOf = result.anyOf.map((subSchema) =>
+    result.anyOf = result.anyOf.map((subSchema: any) =>
       dereferenceSchema(
         subSchema as JSONSchema7,
         definitions,
@@ -49,7 +50,7 @@ export function dereferenceSchema(
 
   // Handle oneOf
   if (result.oneOf) {
-    result.oneOf = result.oneOf.map((subSchema) =>
+    result.oneOf = result.oneOf.map((subSchema: any) =>
       dereferenceSchema(
         subSchema as JSONSchema7,
         definitions,