/shopify-admin-agentic-image-alt-text

name: shopify-admin-agentic-image-alt-text
role: agentic
description: "Generate and set descriptive alt text on product images so AI agents (which can't 'see' pixels) can understand and recommend what each product looks like."
toolkit: shopify-admin, shopify-admin-execution
api_version: "2025-01"
graphql_operations:
  - products:query
  - fileUpdate:mutation
status: stable
compatibility: Claude Code, Cursor, Codex, Gemini CLI
audit_signals:
  - listing-image-alt-text

Purpose

An AI shopping agent reads image **alt text** to understand a product's appearance — color, material, style, use. Blank or filename-style alt text ("IMG_2931.jpg") tells the agent nothing, so it can't match the product to a visual query ("red linen midi dress") or describe it to a shopper. This skill finds product images with missing or low-value alt text and writes concise, descriptive alt text derived from the product's title, options, type, and tags. Fixes the agentiq.report finding `listing-image-alt-text`.

Prerequisites

• Authenticated Shopify CLI session (`shopify auth login --store <domain>`)
• Required API scopes: `read_products`, `write_products`, `write_files`

Parameters

All skills accept these universal parameters:

| Parameter | Type | Required | Default | Description | |-----------|--------|----------|---------|-------------| | store | string | yes | — | Store domain (e.g., mystore.myshopify.com) | | format | string | no | human | Output format: `human` (default) or `json` | | dry_run | bool | no | false | Preview mutations without executing |

Skill-specific parameters:

| Parameter | Type | Required | Default | Description | |-----------|------|----------|---------|-------------| | collection_id | string | no | — | Limit to a collection GID | | tag | string | no | — | Limit to a product tag | | overwrite | bool | no | false | If true, also rewrite filename-style / placeholder alt text; if false, only fill blanks | | max_chars | int | no | 125 | Alt-text length cap (accessibility + agent-readability) |

Safety

> ⚠️ Step 3 (`fileUpdate`) writes alt text to live media. With `overwrite: true` it replaces existing alt text, which is not bulk-reversible. Run `dry_run: true` first and review the proposed alt text per image. Default (`overwrite: false`) only fills blanks and is low-risk.

Workflow Steps

1. **OPERATION:** `products` — query **Inputs:** `first: 250`, optional collection/tag filter; fields `title`, `productType`, `tags`, `options`, `media{ MediaImage{ id image{ altText } } }`; paginate until done. **Expected output:** Product media with current alt text + the product context needed to generate good alt text.

2. **COMPUTE (no API):** for each image with blank (or, if `overwrite`, placeholder) alt text, compose alt text from `title` + relevant option values (color/material/style) + product type, trimmed to `max_chars`. Emit a preview table (image id → proposed alt).

3. **OPERATION:** `fileUpdate` — mutation **Inputs:** `files: [{ id: <MediaImage id>, alt: <generated alt> }]` in batches (≤ 25). **Expected output:** Updated files; collect `userErrors`.

GraphQL Operations

# products:query — validated against api_version 2025-01
query AltTextProducts($first: Int!, $after: String, $query: String) {
  products(first: $first, after: $after, query: $query) {
    edges {
      node {
        id
        title
        productType
        tags
        options { name values }
        media(first: 20) {
          edges {
            node { ... on MediaImage { id image { altText url } } }
          }
        }
      }
    }
    pageInfo { hasNextPage endCursor }
  }
}

# fileUpdate:mutation — validated against api_version 2025-01
mutation AltTextUpdate($files: [FileUpdateInput!]!) {
  fileUpdate(files: $files) {
    files { ... on MediaImage { id alt } }
    userErrors { field message code }
  }
}

Session Tracking

**Claude MUST emit the following output at each stage. This is mandatory.**

**On start**, emit:

╔══════════════════════════════════════════════╗
║  SKILL: <skill name>                         ║
║  Store: <store domain>                       ║
║  Started: <YYYY-MM-DD HH:MM UTC>             ║
╚══════════════════════════════════════════════╝

**After each step**, emit:

[N/TOTAL] <QUERY|MUTATION>  <OperationName>
          → Params: <brief summary of key inputs>
          → Result: <count or outcome>

If `dry_run: true`, prefix every mutation step with `[DRY RUN]` and do not execute it.

**On completion**, emit:

For `format: human` (default):

══════════════════════════════════════════════
OUTCOME SUMMARY
  <Metric label>:   <value>
  Errors:           0
  Output:           <filename or "none">
══════════════════════════════════════════════

For `format: json`, emit:

{
  "skill": "<skill-slug>",
  "store": "<domain>",
  "started_at": "<ISO8601>",
  "completed_at": "<ISO8601>",
  "dry_run": false,
  "steps": [
    {
      "step": 1,
      "operation": "<OperationName>",
      "type": "query",
      "params_summary": "<string>",
      "result_summary": "<string>",
      "skipped": false
    }
  ],
  "outcome": {
    "metric_key": 0,
    "errors": 0,
    "output_file": null
  }
}

Output Format

`human`: count of images updated + a CSV (`product, image_id, old_alt, new_alt`). `json`: `{ images_updated, images_skipped, errors, output_file }`.

Error Handling

| Error | Cause | Recovery | |-------|-------|----------| | `THROTTLED` | API rate limit | Wait 2s, retry up to 3 times | | `userErrors` non-empty | Invalid file id / not a MediaImage | Log message, skip, continue | | Alt exceeds limit | Generated text too long | Trim to `max_chars` at a word boundary |

Best Practices

• Lead the alt text with the concrete noun + distinguishing attribute ("Charcoal merino crew-neck sweater"), not marketing fluff — that's what agents match on.
• Keep `overwrite