diff --git a/tests/js/image-helpers.test.js b/tests/js/image-helpers.test.js
index 65878ed..885f052 100644
--- a/tests/js/image-helpers.test.js
+++ b/tests/js/image-helpers.test.js
@@ -1,7 +1,52 @@
 // Run with: node --test tests/js/
 const test = require("node:test");
 const assert = require("node:assert/strict");
-const { formatImageCaption, workflowDocumentHtml } = require("../../web/js/image-helpers.js");
+const {
+    formatImageCaption,
+    workflowDocumentHtml,
+    autotagSingleBody,
+} = require("../../web/js/image-helpers.js");
+
+const WD14 = { modelType: "wd14-vit", generalThreshold: 0.35, characterThreshold: 0.85, prompt: "ignored" };
+const CAPTION = { modelType: "blip", generalThreshold: 0.35, characterThreshold: 0.85, prompt: "describe it" };
+
+test("autotagSingleBody sends image_id for a database row", () => {
+    const body = autotagSingleBody({ id: 42, prompt_id: 7, image_path: "/out/a.png" }, WD14);
+    assert.equal(body.image_id, 42);
+    assert.equal("path" in body, false);
+});
+
+test("autotagSingleBody sends path for an output-folder entry whose id is a digest", () => {
+    const body = autotagSingleBody({ id: "3f2a9c1b0d4e5f67", path: "/out/sub/a.png", filename: "a.png" }, WD14);
+    assert.equal(body.path, "/out/sub/a.png");
+    assert.equal("image_id" in body, false);
+});
+
+test("autotagSingleBody prefers path when a numeric-looking string id has no prompt link", () => {
+    const body = autotagSingleBody({ id: "1234567890abcdef", path: "/out/b.png" }, WD14);
+    assert.deepEqual(Object.keys(body).filter((k) => k === "path" || k === "image_id"), ["path"]);
+});
+
+test("autotagSingleBody adds wd14 thresholds and no prompt", () => {
+    const body = autotagSingleBody({ id: 1 }, WD14);
+    assert.equal(body.model_type, "wd14-vit");
+    assert.equal(body.general_threshold, 0.35);
+    assert.equal(body.character_threshold, 0.85);
+    assert.equal("prompt" in body, false);
+});
+
+test("autotagSingleBody adds the prompt for caption models and no thresholds", () => {
+    const body = autotagSingleBody({ id: 1 }, CAPTION);
+    assert.equal(body.model_type, "blip");
+    assert.equal(body.prompt, "describe it");
+    assert.equal("general_threshold" in body, false);
+});
+
+test("autotagSingleBody does not mutate its inputs", () => {
+    const image = Object.freeze({ id: 1 });
+    const settings = Object.freeze({ ...WD14 });
+    assert.doesNotThrow(() => autotagSingleBody(image, settings));
+});
 
 const XSS = '"><img src=x onerror=1>';
 const formatFileSize = (bytes) => `${bytes} B`;
diff --git a/web/js/admin.js b/web/js/admin.js
index bec9dd4..bf86496 100644
--- a/web/js/admin.js
+++ b/web/js/admin.js
@@ -3671,16 +3671,8 @@ Seed: ${this.currentMetadata.seed || 'Unknown'}`;
                 this.autoTagState.tagsExpanded = false;  // Reset accordion for new image
 
                 try {
-                    const requestBody = {
-                        image_id: image.id,
-                        model_type: this.autoTagState.modelType,
-                    };
-                    if (this.autoTagState.modelType.startsWith('wd14')) {
-                        requestBody.general_threshold = this.autoTagState.generalThreshold;
-                        requestBody.character_threshold = this.autoTagState.characterThreshold;
-                    } else {
-                        requestBody.prompt = this.autoTagState.prompt;
-                    }
+                    // Review rows come from /images/all (database ids), so this resolves to image_id
+                    const requestBody = ImageHelpers.autotagSingleBody(image, this.autoTagState);
 
                     const response = await fetch('/prompt_manager/autotag/single', {
                         method: 'POST',
diff --git a/web/js/gallery.js b/web/js/gallery.js
index c63b5ba..73e31ab 100644
--- a/web/js/gallery.js
+++ b/web/js/gallery.js
@@ -3380,16 +3380,8 @@ Seed: ${this.currentMetadata.seed || 'Unknown'}`;
                 document.getElementById('reviewTagsContainer').innerHTML = '<div class="text-pm-secondary">Generating tags...</div>';
 
                 try {
-                    const requestBody = {
-                        image_id: image.id,
-                        model_type: this.autoTagState.modelType,
-                    };
-                    if (this.autoTagState.modelType.startsWith('wd14')) {
-                        requestBody.general_threshold = this.autoTagState.generalThreshold;
-                        requestBody.character_threshold = this.autoTagState.characterThreshold;
-                    } else {
-                        requestBody.prompt = this.autoTagState.prompt;
-                    }
+                    // Gallery entries come from /images/output: id is a path digest, so address by path
+                    const requestBody = ImageHelpers.autotagSingleBody(image, this.autoTagState);
 
                     const response = await fetch('/prompt_manager/autotag/single', {
                         method: 'POST',
diff --git a/web/js/image-helpers.js b/web/js/image-helpers.js
index 9c29786..9e07433 100644
--- a/web/js/image-helpers.js
+++ b/web/js/image-helpers.js
@@ -62,7 +62,34 @@
         ].join("\n");
     }
 
-    const api = { formatImageCaption, workflowDocumentHtml };
+    /**
+     * Body for POST /prompt_manager/autotag/single.
+     *
+     * Database rows (admin review, /images/all) have an integer id the server
+     * looks up; output-folder entries (gallery review, /images/output) have a
+     * path digest as id, which would 404, so those are addressed by path.
+     *
+     * @param {{id?: unknown, path?: unknown}} image
+     * @param {{modelType: string, generalThreshold?: number, characterThreshold?: number, prompt?: string}} settings
+     * @returns {object} JSON-serialisable request body
+     */
+    function autotagSingleBody(image, settings) {
+        const entry = image || {};
+        const target =
+            typeof entry.path === "string" && entry.path && !Number.isInteger(entry.id)
+                ? { path: entry.path }
+                : { image_id: entry.id };
+        const modelType = String(settings.modelType || "");
+        const params = modelType.startsWith("wd14")
+            ? {
+                  general_threshold: settings.generalThreshold,
+                  character_threshold: settings.characterThreshold,
+              }
+            : { prompt: settings.prompt };
+        return { ...target, model_type: modelType, ...params };
+    }
+
+    const api = { formatImageCaption, workflowDocumentHtml, autotagSingleBody };
     if (typeof module !== "undefined" && module.exports) module.exports = api;
     else root.ImageHelpers = api;
 })(typeof window !== "undefined" ? window : globalThis);