diff --git a/mcp-server/tools/media/upload.js b/mcp-server/tools/media/upload.js
index 121fcea..cb3f444 100644
--- a/mcp-server/tools/media/upload.js
+++ b/mcp-server/tools/media/upload.js
@@ -65,12 +65,12 @@ async function resolveLocalImageAsBase64(imageUrl) {
 export function registerUploadRecordImageTool(server) {
     server.tool(
         "upload_record_image",
-        "Upload an image to a specific record field in Acai CMS. MANDATORY: before calling this tool, you MUST call get_table_schema with minimal=true to find the EXACT upload field name. Look for fields with type='upload'. NEVER guess field names. Table names WITHOUT 'cms_' prefix. recordId is 'num', never 'id'. If the URL came from generate_image, prefer uploadUrl (or fullUrl) over dockerUrl.",
+        "Upload an image to a specific record field in Acai CMS. MANDATORY: before calling this tool, you MUST call get_table_schema with minimal=true to find the EXACT upload field name. Look for fields with type='upload'. NEVER guess field names. Table names WITHOUT 'cms_' prefix. recordId is 'num', never 'id'. If the URL came from generate_image, prefer uploadUrl (or fullUrl) over dockerUrl. For a LOCAL or pasted image (a file on your machine, no public URL): save it into the synced project folder cms/uploads/chat/<name>.ext, wait for the sync to push it, then pass its PROJECT-RELATIVE path (e.g. 'cms/uploads/chat/foto.png') as imageUrl. NEVER pass a data-URI/base64 nor spin up a localhost server.",
         withAuthParams({
             tableName: z.string().describe("Table name without 'cms_' prefix (e.g., 'productos')"),
             recordId: z.string().describe("Record 'num' (primary key)"),
             fieldName: z.string().describe("EXACT field name from the schema. MUST match a field with type 'upload' from get_table_schema or get_module_config_vars. Do NOT guess."),
-            imageUrl: z.string().describe("URL of the image to upload"),
+            imageUrl: z.string().describe("Image to upload: an http(s) URL, OR a project-relative path to a file already synced to the project (e.g. 'cms/uploads/chat/foto.png'). For local/pasted images use the relative-path form. NOT a data-URI or base64."),
             alt: z.string().optional().describe("Alt text for the image (optional)"),
         }),
         { readOnlyHint: false, destructiveHint: false },
@@ -83,19 +83,33 @@ export function registerUploadRecordImageTool(server) {
                 );
                 if (validationError) return validationError;
 
-                // Rechazar data-URI / base64 crudo: derivar el nombre de fichero
-                // del base64 produce nombres de miles de chars que revientan
-                // file_put_contents ("File name too long"). Exigir URL http real.
+                // Aceptamos: URL http(s), ruta absoluta del servidor, o RUTA
+                // RELATIVA del proyecto (p.ej. "cms/uploads/chat/foto.png"). Para
+                // una imagen local/pegada el flujo correcto es guardarla en una
+                // carpeta sincronizada NO truncada (cms/uploads/chat/ o
+                // cms/uploads/generated/), dejar que el sync la suba a test y pasar
+                // aquí su ruta relativa: el server lee los bytes de disco vía
+                // resolve_image_source (sin base64 por el modelo).
+                // Seguimos rechazando data-URI / base64 crudo: derivar el nombre
+                // de un base64 gigante revienta file_put_contents ("File name too
+                // long"). El tope de longitud + charset de ruta lo descartan.
                 const trimmedImage = imageUrl.trim();
                 const isHttpUrl = /^https?:\/\//i.test(trimmedImage);
-                const isFsPath = trimmedImage.startsWith("/") && !trimmedImage.startsWith("//");
-                if (!isHttpUrl && !isFsPath) {
+                const isAbsPath = trimmedImage.startsWith("/") && !trimmedImage.startsWith("//");
+                const isRelPath = !isHttpUrl && !isAbsPath
+                    && !/^[a-z][a-z0-9+.-]*:/i.test(trimmedImage)   // sin esquema (data:, file:...)
+                    && !trimmedImage.includes("..")
+                    && trimmedImage.length <= 512
+                    && /^[\w./ -]+$/.test(trimmedImage);             // charset de ruta (no base64)
+                if (!isHttpUrl && !isAbsPath && !isRelPath) {
                     return {
                         content: [{
                             type: "text",
                             text: JSON.stringify({
-                                error: "imageUrl must be an http(s) URL, not a data URI or raw base64. " +
-                                    "First upload the image with the 'upload_image_to_assets' tool and pass the returned imageUrl here."
+                                error: "imageUrl debe ser una URL http(s) o una ruta relativa del proyecto " +
+                                    "(p.ej. 'cms/uploads/chat/foto.png'), no un data-URI ni base64 crudo. " +
+                                    "Para una imagen local/pegada: guárdala en cms/uploads/chat/ (sincronizada a test), " +
+                                    "espera a que el sync la suba y pasa su ruta relativa."
                             }, null, 2)
                         }],
                         isError: true,
@@ -221,7 +235,7 @@ export function registerUploadRecordImageTool(server) {
             recordId: z.string().describe("Record 'num' (primary key)"),
             fieldName: z.string().describe("Upload field name"),
             uploadId: z.string().describe("Upload ID to replace (get from list_record_uploads)"),
-            imageUrl: z.string().describe("URL of the new image to upload"),
+            imageUrl: z.string().describe("New image: an http(s) URL, OR a project-relative path to a file already synced (e.g. 'cms/uploads/chat/foto.png'). For local/pasted images use the relative-path form. NOT a data-URI or base64."),
             alt: z.string().optional().describe("Alt text for the image (optional)"),
         }),
         { readOnlyHint: false, destructiveHint: false },