diff --git a/README.md b/README.md
index 8144720..15f6f74 100644
--- a/README.md
+++ b/README.md
@@ -89,6 +89,43 @@ get_document({
 })
 ```
 
+#### update_document
+Update metadata on an existing document. Use this to correct the document date, title, correspondent, type, or tags after a document has been added to Paperless-NGX.
+
+> **Note on tags:** The `tags` parameter is a full replacement — it overwrites all existing tags on the document. To add or remove individual tags without affecting others, use `bulk_edit_documents` with `add_tag` or `remove_tag` instead.
+
+Parameters:
+- id: Document ID to update
+- title (optional): New title for the document
+- created (optional): Document date in ISO format (YYYY-MM-DD). Corrects the date to match the actual document date, not the scan/upload date.
+- correspondent (optional): ID of a correspondent, or null to clear
+- document_type (optional): ID of a document type, or null to clear
+- storage_path (optional): ID of a storage path, or null to use default
+- tags (optional): Full list of tag IDs to assign — replaces all existing tags
+- archive_serial_number (optional): Integer archive serial number, or null to clear
+
+```typescript
+// Fix a document date and assign a correspondent
+update_document({
+  id: 123,
+  created: "2024-11-18",
+  correspondent: 7
+})
+
+// Update title and document type
+update_document({
+  id: 456,
+  title: "Annual Pension Statement 2025",
+  document_type: 3
+})
+
+// Replace all tags
+update_document({
+  id: 789,
+  tags: [2, 5, 11]
+})
+```
+
 #### search_documents
 Full-text search across documents.
 
diff --git a/src/api/PaperlessAPI.ts b/src/api/PaperlessAPI.ts
index 5f5bd21..92b4a56 100644
--- a/src/api/PaperlessAPI.ts
+++ b/src/api/PaperlessAPI.ts
@@ -106,6 +106,13 @@ export class PaperlessAPI {
     return this.request(`/documents/${id}/`);
   }
 
+  async updateDocument(id: number, data: Record<string, any>) {
+    return this.request(`/documents/${id}/`, {
+      method: "PATCH",
+      body: JSON.stringify(data),
+    });
+  }
+
   async searchDocuments(query, page?, pageSize?) {
     const params = new URLSearchParams();
     params.set("query", query);
diff --git a/src/tools/correspondents.ts b/src/tools/correspondents.ts
index 87504f0..06ab32e 100644
--- a/src/tools/correspondents.ts
+++ b/src/tools/correspondents.ts
@@ -7,7 +7,8 @@ export function registerCorrespondentTools(server: McpServer, api) {
     "Retrieve all available correspondents (people, companies, organizations that send/receive documents). Returns names and automatic matching patterns for document assignment.",
     { }, async (args, extra) => {
     if (!api) throw new Error("Please configure API connection first");
-    return api.getCorrespondents();
+    const result = await api.getCorrespondents();
+    return { content: [{ type: "text" as const, text: JSON.stringify(result, null, 2) }] };
   });
 
   server.tool(
@@ -22,7 +23,17 @@ export function registerCorrespondentTools(server: McpServer, api) {
     },
     async (args, extra) => {
       if (!api) throw new Error("Please configure API connection first");
-      return api.createCorrespondent(args);
+      const algorithmMap: Record<string, number> = {
+        any: 1, all: 2, exact: 3, "regular expression": 4, fuzzy: 5,
+      };
+      const payload = {
+        ...args,
+        ...(args.matching_algorithm !== undefined && {
+          matching_algorithm: algorithmMap[args.matching_algorithm],
+        }),
+      };
+      const result = await api.createCorrespondent(payload);
+      return { content: [{ type: "text" as const, text: JSON.stringify(result, null, 2) }] };
     }
   );
 
diff --git a/src/tools/documentTypes.ts b/src/tools/documentTypes.ts
index e7b4536..9f50a01 100644
--- a/src/tools/documentTypes.ts
+++ b/src/tools/documentTypes.ts
@@ -8,7 +8,8 @@ export function registerDocumentTypeTools(server, api) {
     // No parameters - returns all available document types
   }, async (args, extra) => {
     if (!api) throw new Error("Please configure API connection first");
-    return api.getDocumentTypes();
+    const result = await api.getDocumentTypes();
+    return { content: [{ type: "text" as const, text: JSON.stringify(result, null, 2) }] };
   });
 
   server.tool(
@@ -23,7 +24,17 @@ export function registerDocumentTypeTools(server, api) {
     },
     async (args, extra) => {
       if (!api) throw new Error("Please configure API connection first");
-      return api.createDocumentType(args);
+      const algorithmMap: Record<string, number> = {
+        any: 1, all: 2, exact: 3, "regular expression": 4, fuzzy: 5,
+      };
+      const payload = {
+        ...args,
+        ...(args.matching_algorithm !== undefined && {
+          matching_algorithm: algorithmMap[args.matching_algorithm],
+        }),
+      };
+      const result = await api.createDocumentType(payload);
+      return { content: [{ type: "text" as const, text: JSON.stringify(result, null, 2) }] };
     }
   );
 
diff --git a/src/tools/documents.ts b/src/tools/documents.ts
index 1381692..ceb8508 100644
--- a/src/tools/documents.ts
+++ b/src/tools/documents.ts
@@ -91,7 +91,42 @@ export function registerDocumentTools(server, api) {
     },
     async (args, extra) => {
       if (!api) throw new Error("Please configure API connection first");
-      return api.getDocument(args.id);
+      const result = await api.getDocument(args.id);
+      const { content: _ocr, ...meta } = result;
+      return { content: [{ type: "text" as const, text: JSON.stringify(meta, null, 2) }] };
+    }
+  );
+
+  server.tool(
+    "update_document",
+    "Update metadata for an existing document. Use this to correct or set the document date, title, correspondent, document type, tags, and other fields on a document that is already in Paperless-NGX.",
+    {
+      id: z.number().describe("Unique document ID to update. Get this from list_documents, search_documents, or get_document."),
+      title: z.string().optional().describe("New title for the document."),
+      created: z.string().optional().describe("Document date in ISO format (YYYY-MM-DD or YYYY-MM-DDTHH:mm:ss). Use this to set the date to the actual date on the document — Paperless often defaults to the upload/scan date instead."),
+      correspondent: z.number().nullable().optional().describe("ID of correspondent to assign, or null to clear. Use list_correspondents to get valid IDs."),
+      document_type: z.number().nullable().optional().describe("ID of document type to assign, or null to clear. Use list_document_types to get valid IDs."),
+      storage_path: z.number().nullable().optional().describe("ID of storage path to assign, or null to use default."),
+      tags: z.array(z.number()).optional().describe("Full list of tag IDs to assign. Replaces all existing tags on the document. Use list_tags to get valid IDs."),
+      archive_serial_number: z.string().nullable().optional().describe("Archive serial number for physical document cross-reference, or null to clear. Use the same format as post_document (e.g. '2024-001' or '42')."),
+    },
+    async (args, extra) => {
+      if (!api) throw new Error("Please configure API connection first");
+      const { id, ...data } = args;
+      if (Object.keys(data).length === 0) {
+        throw new Error("At least one field must be provided to update.");
+      }
+      try {
+        const result = await api.updateDocument(id, data);
+        // Explicitly return MCP content format. We can't return the raw Paperless document
+        // object because it has a "content" key (OCR text, a string) — the MCP client
+        // validates responses against CallToolResultSchema where content must be ContentBlock[].
+        // Stripping the OCR field and wrapping in the proper format satisfies both constraints.
+        const { content: _ocr, ...meta } = result;
+        return { content: [{ type: "text" as const, text: JSON.stringify(meta, null, 2) }] };
+      } catch (err: any) {
+        return { content: [{ type: "text" as const, text: `Error updating document ${id}: ${err?.message ?? String(err)}` }], isError: true };
+      }
     }
   );
 
@@ -105,7 +140,8 @@ export function registerDocumentTools(server, api) {
     },
     async (args, extra) => {
       if (!api) throw new Error("Please configure API connection first");
-      return api.searchDocuments(args.query, args.page, args.page_size);
+      const result = await api.searchDocuments(args.query, args.page, args.page_size);
+      return { content: [{ type: "text" as const, text: JSON.stringify(result, null, 2) }] };
     }
   );
 
diff --git a/src/tools/tags.ts b/src/tools/tags.ts
index 5447764..a69bae9 100644
--- a/src/tools/tags.ts
+++ b/src/tools/tags.ts
@@ -8,7 +8,8 @@ export function registerTagTools(server, api) {
     // No parameters - returns all available tags
   }, async (args, extra) => {
     if (!api) throw new Error("Please configure API connection first");
-    return api.getTags();
+    const result = await api.getTags();
+    return { content: [{ type: "text" as const, text: JSON.stringify(result, null, 2) }] };
   });
 
   server.tool(