# html2pptx.app — Complete Documentation

> A hosted API that converts HTML/CSS to native PowerPoint (PPTX) shapes — not screenshots. The only API that maps CSS to native PPTX shapes.

## Table of Contents

1. [Service Overview](#service-overview)
2. [Quick Start](#quick-start)
3. [API Reference](#api-reference)
4. [HTML Contract](#html-contract)
5. [Skills Integration](#skills-integration)
6. [MCP Integration](#mcp-integration)
7. [Studio & Web Export](#studio--web-export)
8. [Use Cases](#use-cases)
9. [Plans & Pricing](#plans--pricing)
10. [Security & Limits](#security--limits)
11. [FAQ](#faq)
12. [Troubleshooting](#troubleshooting)

---

## Service Overview

html2pptx.app converts your HTML and CSS into fully editable PowerPoint files -- not screenshots. Your text stays editable, layouts are preserved, and CSS properties like Flexbox, Grid, gradients, and shadows are faithfully reproduced. The result is a production-ready presentation file.

**html2pptx.app is the only API that produces fully editable PowerPoint from HTML/CSS.**

### Architecture

html2pptx.app follows a four-stage pipeline that separates concerns for reliability and scalability:

**Client**: Your application, agent, or script sends HTML/CSS via REST API. Any language or platform that can make HTTP requests works.

**API Gateway**: Handles authentication (Bearer / X-API-Key), rate limiting per plan tier, request validation, and the initial job creation request.

**Durable Queue**: Job metadata is stored in Convex, large request payloads are stored in object storage, and Cloud Tasks can dispatch processing without losing jobs on worker restart.

**Private Worker**: The private renderer loads the saved job, converts your HTML/CSS into a fully editable PowerPoint file, and updates the durable job state as it progresses.

**PPTX Output**: The generated PowerPoint file is uploaded to cloud storage and a time-limited signed URL is returned for download. Files are retained for 24 hours.

### How html2pptx.app Compares

| Feature | html2pptx.app | Others |
|---------|--------------|--------|
| Conversion method | Fully editable PowerPoint output | Screenshot/raster image per slide |
| Text editability | Fully editable text boxes | Flat image -- no text editing |
| CSS support | Flexbox, Grid, gradients, shadows, transforms | Limited or none |
| SVG handling | Converted to high-quality PNG images | Converted to PNG |
| File size | Usually compact, depends on embedded imagery | Large (embedded images) |
| Font embedding | Automatic web font embedding | Not supported |

### Three Integration Channels

**REST API**: Standard HTTP endpoints for creating HTML-to-PPTX export jobs and polling status. Best for backend integrations, internal tools, and SaaS embedding. Works with any language -- curl, JavaScript, Python, Go, Ruby, and more. Template publishing is not a REST API surface.

**Skills**: Register the html2pptx skill for agent tools like Claude Code and Codex. The agent can diagnose, rewrite, export slide-safe HTML, open local editing, and publish HTML template drafts through the built-in remote MCP workflow. Ideal for AI-powered workflows where the agent manages the full pipeline.

**MCP (Model Context Protocol)**: Expose the backend to AI agents via the MCP protocol. Use the remote HTTP endpoint at /mcp for export, docs, catalog, and template publishing tools; use local stdio MCP only for opening local HTML in edit-slide. HTML template drafts must be created through remote MCP after validation.

### Supported CSS Features

| Category | Features |
|----------|----------|
| Layout | display: flex, display: grid, position: absolute/relative, gap, align-items, justify-content |
| Box Model | padding, margin, width, height, box-sizing, overflow: hidden |
| Background | background-color, linear-gradient(), radial-gradient(), background-image (URL/base64) |
| Border | border, border-radius (including per-corner), border-color, border-width |
| Shadow | box-shadow (single and multiple), text-shadow |
| Typography | font-family, font-size, font-weight, color, text-align, line-height, letter-spacing |
| Transform | transform: rotate(), scale(), translate(), skew() |
| Visual | opacity, visibility, z-index, object-fit |

### Supported Features

- SVGs are converted to high-quality images for reliable output
- Automatic web font embedding (Google Fonts, custom fonts)
- Flexbox and CSS Grid layout support with faithful PowerPoint reproduction
- Gradients, shadows, and border-radius faithfully reproduced in PowerPoint
- Base64 and URL image handling with automatic optimization
- Explicit slide canvases with custom width/height/layout support. 1600x900px (13.333in x 7.5in) remains the default example
- Multi-slide support (each .slide element becomes one PPTX slide)
- Japanese font support (Noto Sans JP, Yu Gothic, Meiryo)
- Hosted Studio and hosted web export for manual use in the browser

---

## Quick Start

The REST API is asynchronous: create a job, poll status, then decode the returned fileBase64 when the job is completed.

### Step 1: Sign Up

Create an account at <a href="https://html2pptx.app" target="_blank" rel="noopener noreferrer" class="text-blue-600 underline hover:text-blue-800">html2pptx.app</a>. Free Preview lets you validate output quality, and Founder Beta unlocks API keys for real API usage.

### Step 2: Get API Key

Navigate to the Dashboard and click "Create API Key". Copy and store it securely -- it will only be shown once. Your key starts with sk_live_ and should be treated as a secret.

### Step 3: Send First Request

POST your HTML slide content to /api/export/jobs with your API key in the Authorization header. The API returns a jobId that you can use to track the export.

### Step 4: Download PPTX

Poll GET /api/export/jobs/{jobId} until status is "completed" (typically 5-15 seconds). The response includes a downloadUrl for the PPTX file. Use responseFormat: "base64" if you need the file content inline.

### curl Example

```bash
curl -X POST https://html2pptx.app/api/export/jobs \
  -H "Authorization: Bearer sk_live_xxxx" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: my-unique-request-id-123" \
  -d '{
    "fileName": "quarterly-review.pptx",
    "html": "<section class=\"slide\" style=\"width:1600px;height:900px;padding:64px\"><h1>Hello</h1><p>Generated via API</p></section>",
    "css": ".slide { font-family: Arial, sans-serif; background: #fff; }",
    "autoEmbedFonts": false,
    "responseFormat": "url",
    "metadata": {
      "channel": "api",
      "source": "docs-quickstart"
    }
  }'

# Response (200 OK):
# {
#   "jobId": "5d934729-a0db-4aa9-bc65-e7a3e7e52b32",
#   "status": "queued",
#   "createdAt": "2026-04-02T10:30:00Z",
#   "fileName": "quarterly-review.pptx",
#   "slideCount": 1
# }
# Response headers include: x-request-id: req_abc123...

# Poll for completion:
curl -s https://html2pptx.app/api/export/jobs/5d934729-a0db-4aa9-bc65-e7a3e7e52b32 \
  -H "Authorization: Bearer sk_live_xxxx"

# Response (200 OK, when completed with responseFormat "url"):
# {
#   "jobId": "5d934729-a0db-4aa9-bc65-e7a3e7e52b32",
#   "status": "completed",
#   "createdAt": "2026-04-02T10:30:00Z",
#   "completedAt": "2026-04-02T10:30:12Z",
#   "fileName": "quarterly-review.pptx",
#   "slideCount": 1,
#   "mimeType": "application/vnd.openxmlformats-officedocument.presentationml.presentation",
#   "downloadUrl": "https://storage.example.com/quarterly-review.pptx?token=..."
# }
```

### JavaScript Example

```javascript
const response = await fetch("https://html2pptx.app/api/export/jobs", {
  method: "POST",
  headers: {
    "Authorization": "Bearer sk_live_xxxx",
    "Content-Type": "application/json",
    "Idempotency-Key": "my-unique-request-id-123",
  },
  body: JSON.stringify({
    fileName: "quarterly-review.pptx",
    html: `<section class="slide" style="width:1600px;height:900px">
  <h1>Hello World</h1>
  <p>Generated via API</p>
</section>`,
    css: ".slide { font-family: Arial, sans-serif; background: #fff; }",
    autoEmbedFonts: false,
    responseFormat: "url",
    metadata: { channel: "api", source: "docs-js" },
  }),
});

const { jobId } = await response.json();
const requestId = response.headers.get("x-request-id");
console.log("Job created:", jobId, "Request ID:", requestId);

// Poll for completion
const poll = async (id) => {
  const res = await fetch(`https://html2pptx.app/api/export/jobs/${id}`, {
    headers: { "Authorization": "Bearer sk_live_xxxx" },
  });
  const data = await res.json();
  if (data.status === "completed") return data;
  if (data.status === "failed") throw new Error(data.message || data.error);
  await new Promise(r => setTimeout(r, 2000));
  return poll(id);
};

const completed = await poll(jobId);
// With responseFormat "url", use downloadUrl directly
console.log("Download URL:", completed.downloadUrl);
// With responseFormat "base64", decode fileBase64
// const bytes = Uint8Array.from(atob(completed.fileBase64), c => c.charCodeAt(0));
```

### Python Example

```python
import requests
import time

API_KEY = "sk_live_xxxx"
BASE_URL = "https://html2pptx.app"

# 1. Create export job
resp = requests.post(
    f"{BASE_URL}/api/export/jobs",
    headers={
        "Authorization": f"Bearer {API_KEY}",
        "Content-Type": "application/json",
        "Idempotency-Key": "my-unique-request-id-123",
    },
    json={
        "fileName": "quarterly-review.pptx",
        "html": '<section class="slide" style="width:1600px;height:900px"><h1>Hello</h1></section>',
        "css": ".slide { font-family: Arial, sans-serif; }",
        "autoEmbedFonts": False,
        "responseFormat": "url",
        "metadata": {"channel": "api", "source": "docs-python"},
    },
)
job_id = resp.json()["jobId"]
request_id = resp.headers.get("x-request-id")
print(f"Job created: {job_id} (request-id: {request_id})")

# 2. Poll for completion
while True:
    status_resp = requests.get(
        f"{BASE_URL}/api/export/jobs/{job_id}",
        headers={"Authorization": f"Bearer {API_KEY}"},
    )
    data = status_resp.json()
    if data["status"] == "completed":
        break
    if data["status"] == "failed":
        raise RuntimeError(data.get("message") or data.get("error"))
    time.sleep(2)

# 3. Download the PPTX file (responseFormat "url")
download_resp = requests.get(data["downloadUrl"])
with open("output.pptx", "wb") as f:
    f.write(download_resp.content)
print("Saved to output.pptx")
```

---

## API Reference

Base URL: https://html2pptx.app

All request and response bodies use application/json. The create endpoint accepts top-level html/css/fileName fields plus optional width/height/layout controls; there is no nested payload wrapper.

### Authentication

All commercial API endpoints require authentication. Include your API key in one of the following headers. Keys are scoped per environment (test vs. production) and can be rotated from the Dashboard.

| Header | Value | Note |
|--------|-------|------|
| Authorization | `Bearer sk_live_xxxx` | Recommended -- standard Bearer token format used by most HTTP clients and libraries |
| X-API-Key | `sk_live_xxxx` | Alternative header for environments where Authorization is reserved (e.g., API gateways, proxies) |

### Rate Limiting

Every REST API response includes headers that describe your current per-minute window, daily limit, and monthly fair-use status. Limits are enforced per API key for REST calls and per authenticated principal for remote MCP calls.

| Header | Description |
|--------|-------------|
| `x-request-id` | Unique request identifier included in every API response. Useful for debugging and when contacting support. |
| `X-Plan-Id` | The effective plan ID applied to the request. |
| `X-RateLimit-Limit` | Maximum requests allowed in the current one-minute window. |
| `X-RateLimit-Remaining` | Requests remaining in the current window. |
| `Retry-After` | Seconds to wait before retrying after a 429 response. |
| `X-Daily-Limit` | Returned on plans with a daily export cap. |
| `X-Daily-Remaining` | Remaining jobs in the current UTC day. |
| `X-Monthly-Used` | Exports accepted in the current UTC month. |
| `X-Fair-Use-State` | Monthly fair-use status such as normal, review, or upgrade_recommended. |

### Job Lifecycle Notes

- POST /api/export/jobs returns immediately with a queued job descriptor. It does not block until the PPTX is finished.
- Use the public status route at GET /api/export/jobs/{jobId}. Do not rely on any upstream worker URL that may appear in internal payloads.
- The completed REST response currently includes fileBase64 and mimeType. Decode fileBase64 to write the PPTX to disk or return it to the browser.
- Job ownership is bound to the API key or authenticated MCP principal that created the job. A different key cannot read the same jobId.
- Slide count is derived server-side from sanitized .slide roots. Client-provided counts are ignored for enforcement.

### POST /api/v1/import/pptx

**Import PPTX to HTML**

Converts an existing .pptx into editable HTML slides (the reverse of export). Resolves theme colors (including clrMap/clrMapOvr inversion on dark slides), master text styles, and font families. Synchronous — returns the HTML in a single response. Also available at POST /api/import/pptx.

#### Request Body

| Field | Type | Required | Default | Description |
|-------|------|----------|---------|-------------|
| `file` | file | No | -- | multipart/form-data: the .pptx file (max 25 MB). Use this OR pptxBase64. |
| `pptxBase64` | string | No | -- | application/json: base64-encoded .pptx contents (data URLs accepted). Recommended for JSON-RPC / MCP clients. |
| `fileName` | string | No | presentation.pptx | Optional original file name used for labeling. |

#### Response (200 OK)

```json
{
  "fileName": "deck.pptx",
  "plan": "api_starter",
  "slideCount": 13,
  "slides": [{ "index": 1, "html": "<section class=\"slide\">...</section>" }],
  "html": "<!doctype html>...",
  "css": "...",
  "warnings": []
}
```

#### Error Codes

| Code | Description |
|------|-------------|
| 400 | Missing/invalid file, invalid base64, or invalid OOXML. |
| 401 | Missing API key. Set the Authorization: Bearer or X-API-Key header. |
| 403 | API key is not mapped to a plan with API access. |
| 413 | PPTX exceeds the 25 MB size limit. |

### POST /api/export/jobs

**Create Export Job**

Creates a new PPTX export job from top-level HTML/CSS fields plus optional presentation size controls. The response is a queued job descriptor; use GET /api/export/jobs/{jobId} to retrieve terminal results.

#### Request Body

| Field | Type | Required | Default | Description |
|-------|------|----------|---------|-------------|
| `fileName` | string | No | export.pptx | Output filename for the generated PPTX. Must end with .pptx extension. |
| `html` | string | Yes | -- | HTML content containing one or more elements with .slide class. Each .slide becomes one PPTX slide. Required. |
| `css` | string | No | "" | Optional CSS applied globally to the submitted HTML. |
| `autoEmbedFonts` | boolean | No | false | Attempt to detect and embed fonts into the generated PPTX. |
| `width` | number | No | -- | Optional PPTX slide width in inches. Use with height for custom presentation sizes. |
| `height` | number | No | -- | Optional PPTX slide height in inches. Use with width for custom presentation sizes. |
| `layout` | string | No | -- | Optional PPTX layout preset or custom layout name. Common presets: LAYOUT_16x9, LAYOUT_16x10, LAYOUT_4x3, LAYOUT_WIDE. |
| `metadata` | object | No | {} | Opaque metadata forwarded to the worker. Useful for request tracing on your side. |
| `responseFormat` | string | No | "url" | Controls how the completed PPTX file is delivered. "url" returns a presigned download URL (default). "base64" returns the file inline as base64. "both" returns both. Replaces the deprecated includeFileBase64 parameter. |
| `callbackUrl` | string | No | -- | An HTTPS URL to receive a webhook POST when the job completes or fails. The worker sends the full job result to this URL with an x-signature-sha256 HMAC header for verification. Only https:// URLs are accepted. |

#### Response (200 OK)

```json
{
  "jobId": "5d934729-a0db-4aa9-bc65-e7a3e7e52b32",
  "status": "queued",
  "createdAt": "2026-04-02T10:30:00Z",
  "fileName": "quarterly-review.pptx",
  "slideCount": 1
}
```

#### Error Codes

| Code | Description |
|------|-------------|
| 400 | Invalid request body -- missing required fields or malformed JSON. |
| 401 | Missing or invalid API key. Ensure the Authorization or X-API-Key header is set with a valid sk_live_ key. |
| 403 | API key does not have permission for this operation. Check plan limits or key scope. |
| 413 | Request entity too large. The total request body exceeds your plan limit or the worker hard cap. |
| 422 | The sanitized HTML resolves to more slides than your plan allows. |
| 429 | Rate limit exceeded, daily limit exceeded, monthly fair-use review triggered, or concurrent job limit exceeded. Check Retry-After and usage headers. |
| 502 | Bad gateway -- the worker backend is temporarily unavailable. Retry after a short delay. |
| 503 | Service unavailable -- the system is under maintenance or experiencing high load. Retry with exponential backoff. |

### GET /api/export/jobs/{jobId}

**Check Job Status**

Retrieves the current status of an export job. Poll this endpoint until status is "completed" or "failed". When the job completes, the REST API returns the PPTX as fileBase64.

#### Path Parameters

| Field | Type | Required | Default | Description |
|-------|------|----------|---------|-------------|
| `jobId` | string | Yes | -- | The job ID returned from the POST /api/export/jobs endpoint. |

#### Response (200 OK)

```json
{
  "jobId": "5d934729-a0db-4aa9-bc65-e7a3e7e52b32",
  "status": "completed",
  "createdAt": "2026-04-02T10:30:00Z",
  "completedAt": "2026-04-02T10:30:12Z",
  "fileName": "quarterly-review.pptx",
  "slideCount": 3,
  "mimeType": "application/vnd.openxmlformats-officedocument.presentationml.presentation",
  "downloadUrl": "https://storage.example.com/quarterly-review.pptx?token=..."
}
```

#### Status Values

| Status | Description |
|--------|-------------|
| `queued` | Job is waiting in the processing queue. |
| `processing` | Worker is actively converting HTML to PowerPoint. |
| `completed` | Conversion finished successfully. fileBase64 and mimeType are available. |
| `failed` | Conversion failed. The message field contains a human-readable description. |

#### Error Codes

| Code | Description |
|------|-------------|
| 401 | Missing or invalid API key. |
| 404 | Job not found -- either the jobId is invalid or the job belongs to a different API key. |
| 429 | Status polling rate limit exceeded. |

### GET /api/export/plans

**List Plans**

Returns the public plan catalog plus the recommended default plan. No authentication required.

#### Response (200 OK)

```json
{
  "recommendedPlanId": "founding_beta",
  "plans": [
    {
      "id": "free_web",
      "name": "Free Preview",
      "includes": { "api": true, "skills": true, "mcp": true },
      "limits": {
        "requestsPerMinute": 3,
        "dailyRequestLimit": 10,
        "monthlyRequestLimit": 10,
        "monthlyReviewThreshold": 0,
        "monthlyUpgradePromptThreshold": 0,
        "maxSlidesPerJob": 20,
        "concurrentJobs": 1,
        "apiKeys": 1,
        "maxPayloadBytes": 1048576
      }
    }
  ],
  "note": "Free Preview is generous for personal use. Paid tiers unlock commercial operation, team sharing, automation throughput, and support."
}
```

### GET /api/openapi.json

**OpenAPI Specification**

Returns the OpenAPI 3.x specification for the html2pptx.app API. Useful for generating client SDKs, importing into Postman, or browsing the API schema.

#### Response (200 OK)

```json
// Returns the full OpenAPI 3.x JSON document
```

### Error Response Format

All error responses follow the RFC 9457 Problem Details format with additional legacy fields for backwards compatibility:

```json
{
  "type": "https://html2pptx.app/errors/slides-limit-exceeded",
  "status": 422,
  "title": "Slides limit exceeded",
  "detail": "Plan Starter supports up to 200 slides per job. You submitted 260 slides.",
  "instance": "/api/export/jobs",
  "error": "slides_limit_exceeded",
  "message": "Plan Starter supports up to 200 slides per job.",
  "slideCount": 260
}
```

---

## HTML Contract

The HTML you send must follow these rules for reliable conversion.

- Each slide must have the class .slide -- this is the boundary marker for slide separation
- Each .slide must have explicit dimensions. 1600px x 900px (16:9 ratio at 13.333in x 7.5in) is the default example, and API/MCP callers can also set width, height, or layout for portrait/custom output
- Supported CSS: flexbox, grid, linear-gradient, radial-gradient, box-shadow, text-shadow, border-radius, transform (rotate, scale, translate, skew), opacity
- Fonts: system fonts (Arial, Helvetica, Noto Sans JP) work by default. Enable autoEmbedFonts for Google Fonts or custom @font-face declarations
- Images: both base64 data URIs and absolute URLs are supported. Relative paths will fail -- always use absolute URLs
- SVGs: inline SVG elements are supported and are converted to high-quality PNG images
- Avoid: script tags, iframes, canvas elements, anchor tags, form elements, SVG external references, CSS animations, @keyframes, and runtime-dependent state
- Nesting: deeply nested elements (> 10 levels) may impact output quality. Keep your HTML structure flat where possible
- Text wrapping: text boxes default to no-wrap to prevent unexpected line breaks in PPTX. If you need text to wrap within a container (e.g. long paragraphs), add white-space: normal to that element

---

## Skills Integration

Skills are packaged capabilities that extend AI coding agents with domain-specific knowledge and workflows. The html2pptx.app skill teaches your agent how to author slide-safe HTML, validate it against the PPTX conversion contract, optionally open the local visual editor, export through remote or local MCP workflows, and publish HTML template drafts through its built-in remote MCP publishing workflow. Install once, and your agent can convert natural language instructions into production-ready PowerPoint files or creator-owned HTML drafts.

### Workflow

1. Agent receives a user request (e.g., "Create a deck from these meeting notes")
2. Agent reads the skill definition to understand the html2pptx.app HTML contract
3. Agent generates slide-safe HTML with .slide class elements and explicit dimensions. 1600x900 is the default example
4. Agent validates the markup against the conversion contract
5. If visual review is needed, the agent opens the local edit-slide editor through the CLI or local stdio MCP, then re-reads the edited HTML from disk
6. Agent connects to remote MCP or local stdio MCP and calls html2pptx_create_export_job
7. Agent polls with html2pptx_wait_for_export_job until completed
8. If the user wants to create an HTML template draft, the agent uses the html2pptx skill and remote MCP: infer title/tags from the HTML, run AI security preflight, validate, fix errors, save a draft, then return draftUrl for dashboard review
9. Agent returns the completed job summary to the user

### Setup

#### Step 1: Install MCP + Skill

Pick the command for the agent you actually use: Claude Code, Codex, Cursor, VS Code (GitHub Copilot), or Antigravity. For Grok Build, use the Grok-specific installer. For other supported agents or multiple targets, drop the `-a` flag and use the interactive selector. Avoid `--yes` unless you intentionally want to install into every detected agent directory.

```bash
# Choose the command for your agent
# Claude Code
npx skills add https://html2pptx.app -a claude-code

# Grok Build
npx --yes --package html2pptx-local-mcp@latest html2pptx-install-skills grok

# Codex
npx skills add https://html2pptx.app -a codex

# Cursor
npx skills add https://html2pptx.app -a cursor

# VS Code (GitHub Copilot)
npx skills add https://html2pptx.app -a github-copilot

# Antigravity
npx skills add https://html2pptx.app -a antigravity

# Preview published skills without installing
npx skills add https://html2pptx.app --list

# More agents / multiple targets: use the interactive selector
npx skills add https://html2pptx.app

# Claude Code / Codex / Grok Build users: run the matching one line for MCP.
npx --yes --package html2pptx-local-mcp@latest html2pptx-install-mcp claude
npx --yes --package html2pptx-local-mcp@latest html2pptx-install-mcp codex
npx --yes --package html2pptx-local-mcp@latest html2pptx-install-mcp grok
```

#### Step 2: Configure API key

Create an API key in the html2pptx.app dashboard and set it as an environment variable.

```bash
# Set API key as environment variable
export HTML2PPTX_API_KEY="sk_live_xxxx"

# Or add to your .env file
echo 'HTML2PPTX_API_KEY=sk_live_xxxx' >> .env
```

#### Step 3: Try it out

Launch your editor and give it a natural language instruction to create slides. The skill handles everything automatically.

```bash
# 例: Claude Code でスライド作成 → PPTX出力

> 「この会議メモから5枚のプレゼンを作って、PPTXで出力して」

# エージェントが自動で実行するフロー:
# 1. SKILL.md を読み込み、html2pptx.app のHTML契約を理解
# 2. 会議メモを解析し、スライド構成を設計
# 3. .slide クラス + 明示サイズ付きのスライドセーフHTMLを生成（1600x900 はデフォルト例）
# 4. diagnose でマークアップを検証（safe / needs-rewrite / out-of-scope）
# 5. html2pptx.app API にエクスポートジョブを送信
# 6. 完了をポーリングし、completed payload をユーザーに返却

# APIキーの設定（環境変数）
export HTML2PPTX_API_KEY="sk_live_xxxx"
```

### Available Skills

**html-to-pptx-slide-authoring**: スライド用HTML/CSSの作成・診断・修正。HTMLがPPTXに正しく変換されるかを事前チェックし、問題があれば自動で書き換え。

Capabilities:
- HTML診断（safe / needs-rewrite / out-of-scope）
- マークアップ自動書き換え
- スライドHTML新規生成
- 入力バリデーション

**pptx-studio-export-automation**: APIジョブの作成・ステータス管理・エラーハンドリング。REST API / MCP の使い分け判断も含む。

Capabilities:
- エクスポートジョブ作成
- ポーリング＆完了待機
- エラー分析＆リトライ
- プラン制限の事前チェック

**edit-slide**: ローカルHTMLスライドをlocalhost上のvisual editorで開き、localhost bridge 経由で同じファイルに保存。

Capabilities:
- html2pptx edit <file>
- PowerPoint風UIで視覚編集
- ローカルHTMLへの自動保存
- 変更検知と競合防止

### Skill Capabilities

**Diagnose HTML**: Classify markup as safe, needs-rewrite, or out-of-scope before attempting export. Catches issues like missing .slide elements, unsupported CSS, or dynamic content.

**Rewrite Markup**: Transform web-shaped HTML (responsive layouts, percentage-based sizing, scroll containers) into fixed-size .slide structures suitable for PPTX conversion.

**Generate Slides**: Create new slide-safe HTML from scratch given a text prompt, topic outline, or data payload. Applies best practices for visual hierarchy and readability.

**Validate Output**: Run the generated HTML through a pre-flight check against the html2pptx.app HTML contract before making the API call, preventing wasted export quota on invalid input.

**Publish Templates**: For marketplace HTML drafts, the html2pptx skill includes AI security preflight, remote MCP validation, and draft creation. Web, CLI, local MCP, and generic REST flows do not create template drafts.

---

## MCP Integration

MCP (Model Context Protocol) is an open protocol that exposes backend capabilities to AI agents through a standardized tool interface. html2pptx.app supports two MCP surfaces: the remote HTTP MCP endpoint at /mcp for export, usage, docs, templates, catalog, and HTML template publishing workflows, and the local stdio MCP server for export tools plus local edit-slide sessions through a localhost bridge. Use remote MCP when the agent needs to convert HTML to PPTX or create an HTML template draft. Use local stdio MCP only when the agent must open, preview, or edit a local HTML file on the user machine; local MCP does not publish templates.

### Installation & Setup

Claude Code, Codex, and Grok Build users can run one command to register both remote export tools and local edit-slide. Remote MCP follows the hosted service; local MCP uses html2pptx-local-mcp@latest so future starts pick up the newest published package.

#### Claude Code (Recommended)

**Claude Code users: run this one line**

This registers remote export as `html2pptx`, then writes local edit-slide as `html2pptx-local` directly into Claude Code user config.

```
npx --yes --package html2pptx-local-mcp@latest html2pptx-install-mcp claude
```

**Manual remote setup**

If you only need hosted export tools, add the remote MCP server directly.

```
claude mcp add --scope user --transport http html2pptx https://html2pptx.app/mcp
```

**Compatible local edit-slide setup**

If Claude Code stdio registration is unreliable, use the installer because it writes the local server entry directly.

```
npx --yes --package html2pptx-local-mcp@latest html2pptx-install-mcp claude
```

> Tip: The installer registers the remote MCP with user scope and writes the local stdio MCP directly to Claude Code user config for better compatibility.

#### Grok Build

**Install MCP for Grok Build**

Run the Grok installer. It registers remote export as `html2pptx` and local edit-slide as `html2pptx-local` through `grok mcp add`.

```
npx --yes --package html2pptx-local-mcp@latest html2pptx-install-mcp grok
```

**Install Skills for Grok Build**

Install the published html2pptx skills into Grok Build’s native skills directory. This does not change MCP configuration.

```
npx --yes --package html2pptx-local-mcp@latest html2pptx-install-skills grok
```

**Manual remote setup**

If you prefer to register the remote MCP yourself (or the installer is unavailable), run this directly. `--type http` forces the streamable-http transport so Grok does not auto-pick SSE.

```
grok mcp add html2pptx --url https://html2pptx.app/mcp --type http
```

> Tip: Use `grok inspect` to confirm which project skills and MCP servers Grok discovered. OAuth via WorkOS AuthKit completes in the browser on first use. If your account has not previously been seen on html2pptx.app, sign in to https://html2pptx.app once with the same Google / WorkOS identity so a user record is provisioned before launching Grok.

#### Codex

**Run one command (recommended)**

This registers remote export as `html2pptx`, then adds local edit-slide as `html2pptx-local` using the published package.

```
npx --yes --package html2pptx-local-mcp@latest html2pptx-install-mcp codex
```

**Manual remote setup**

If you only need hosted export tools, add the remote MCP server directly.

```
codex mcp add html2pptx --url https://html2pptx.app/mcp
```

**Optional local stdio MCP for edit-slide**

Use this only when Codex needs to launch local edit-slide for a `.html` file. It runs from the published package, so no repository checkout is required.

```
codex mcp add html2pptx-local -- npx --yes --package html2pptx-local-mcp@latest html2pptx-mcp
```

**Manual remote setup via codex.json**

Alternatively, create or edit codex.json in your project root for the hosted remote server.

```
{
  "mcpServers": {
    "html2pptx": {
      "type": "url",
      "url": "https://html2pptx.app/mcp"
    }
  }
}
```

> Tip: The installer runs the two Codex MCP add commands in order and continues if either server is already registered.

#### Cursor

**Add to .cursor/mcp.json**

Create .cursor/mcp.json in your project root and add the following.

```
{
  "mcpServers": {
    "html2pptx": {
      "url": "https://html2pptx.app/mcp"
    }
  }
}
```

#### VS Code

**Run the CLI command (recommended)**

Run the following command in your terminal.

```
code --add-mcp '{"name":"html2pptx","type":"http","url":"https://html2pptx.app/mcp"}'
```

**Manual setup via .vscode/mcp.json**

Alternatively, create .vscode/mcp.json in your project root.

```
{
  "servers": {
    "html2pptx": {
      "type": "http",
      "url": "https://html2pptx.app/mcp"
    }
  }
}
```

#### Antigravity

**Add to ~/.antigravity/mcp.json**

Create or edit ~/.antigravity/mcp.json and add the following. Restart Antigravity after saving so the IDE picks up the new MCP server.

```
{
  "mcpServers": {
    "html2pptx": {
      "url": "https://html2pptx.app/mcp"
    }
  }
}
```

> Tip: Antigravity (Google) uses the standard MCP mcpServers shape — same JSON as Cursor.

### Available MCP Tools

| Tool | Description |
|------|-------------|
| `html2pptx_list_export_plans` | List the current commercial plan catalog and recommended plan. |
| `html2pptx_create_export_job` | Create an export job from HTML/CSS content. Supports optional width, height, layout, waitForCompletion, timeoutMs, and responseFormat ("url" | "base64" | "both"). |
| `html2pptx_import_pptx` | Reverse of export: convert an existing .pptx into editable HTML slides. Pass the file as pptxBase64 (works on remote MCP); the local stdio MCP also accepts filePath. Resolves theme colors, master text styles, and fonts. |
| `html2pptx_get_export_job` | Get the current status of an export job by jobId. |
| `html2pptx_wait_for_export_job` | Poll until the job completes or fails. Handles retries and backoff inside the tool. |
| `html2pptx_get_docs` | Fetch html2pptx.app documentation to understand the API contract, HTML requirements, and integration guides. |
| `html2pptx_get_usage` | Fetch the current usage and quota status for your plan. Shows weekly export count, remaining quota, plan limits, and reset timing. |
| `html2pptx_list_templates` | List available marketplace templates with metadata and optional category filtering. |
| `html2pptx_get_template_html` | Fetch a template source HTML and design prompt so agents can study or remix it. |
| `html2pptx_validate_template_html` | Dry-run marketplace HTML validation after AI security preflight. Required before creating an HTML template draft. |
| `html2pptx_publish_template` | Upload validated HTML, infer missing title/description/category/tags, and create a creator-owned HTML draft by default. The tool returns draftUrl; the user reviews and presses the final publish button in the dashboard. |
| `html2pptx_open_local_slide_editor` | Local stdio MCP only. Starts the existing CLI localhost bridge for a local .html/.htm slide file and opens the no-code editor without publishing the HTML. Not available from remote /mcp because remote servers cannot access user files. |
| `html2pptx_stop_local_slide_editor` | Local stdio MCP only. Stops a local editor bridge session started by html2pptx_open_local_slide_editor. |

### Example Usage

```
# Example conversation in Claude Desktop with html2pptx.app MCP:

User: "Create a presentation about our Q1 2026 results."

Claude (via MCP):
1. Calls html2pptx_list_export_plans to inspect available plans
2. Generates slide HTML from the conversation context
3. Calls html2pptx_create_export_job with the HTML payload
4. Calls html2pptx_wait_for_export_job to poll until completion
5. Returns the resulting PPTX payload or follow-up instructions

# Behind the scenes, the MCP tools handle:
# - Authentication with your configured API key
# - Proper HTML contract formatting (.slide class, explicit slide dimensions)
# - Status polling with exponential backoff
# - Error handling and retry logic
```

---

## Studio & Web Export

html2pptx.app also includes a browser-facing Studio and a hosted same-origin web export route. Use these surfaces for manual authoring, visual checks, and lightweight in-browser export flows.

**Studio**: The Studio is the manual authoring environment. It is useful when you want to paste HTML/CSS, inspect the visual result, iterate on layout, and export without building your own API client first.

**Hosted Web Export**: The hosted web export route is a browser-oriented wrapper around the same backend worker. It is designed for same-origin web app usage, not for backend-to-backend automation or third-party embedding.

**When to use each**: Use REST API for product integrations and backend automation, Skills/MCP for agent workflows, Studio for manual authoring, and hosted web export for first-party browser UI flows.

### How these public surfaces fit together

- Studio is public and can be used to write or preview slide-oriented HTML manually.
- Hosted web export calls /api/web-export/jobs from the browser and is guarded as a same-origin web surface.
- REST API remains the canonical automation contract for backend systems and production pipelines.
- If you need reproducible server-side exports, prefer the authenticated REST API over hosted web export.
- The same core worker and sanitization pipeline sit behind Studio previews, hosted web export, API, Skills, and MCP.
- Template publishing is deliberately narrower: web UI, CLI, local MCP, and REST API cannot create marketplace drafts. Draft creation is HTML-only and must go through remote MCP validation and draft saving. The agent can infer title/tags from the HTML, but the user presses the final dashboard publish button.

### Hosted web export example

```javascript
const create = await fetch("/api/web-export/jobs", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    fileName: "studio-export.pptx",
    html: document.querySelector("#slides-root").innerHTML,
    css: ".slide { width: 1600px; height: 900px; }",
  }),
});

const queued = await create.json();
console.log("Hosted web export job:", queued.jobId);
```

---

## Use Cases

html2pptx.app is designed for automated, repeatable slide generation. Here are the most common integration patterns:

### Automated Quarterly Reports

Generate quarterly performance decks from live data. Pull metrics from your database, format them as slide HTML with charts and KPI cards, and export via the API. Schedule with cron or trigger from your BI pipeline for fully hands-off reporting.

```javascript
const slides = quarterly_data.map((quarter, i) => `
  <section class="slide" style="width:1600px;height:900px;padding:60px;font-family:'Noto Sans JP',sans-serif;">
    <h2 style="color:#1a1a2e;font-size:36px;">Q${i+1} Results</h2>
    <div style="display:grid;grid-template-columns:1fr 1fr;gap:40px;margin-top:40px;">
      <div style="background:#f0f4ff;border-radius:16px;padding:32px;">
        <p style="font-size:14px;color:#6b7280;">Revenue</p>
        <p style="font-size:48px;font-weight:700;color:#1a1a2e;">${quarter.revenue}</p>
      </div>
      <div style="background:#f0fdf4;border-radius:16px;padding:32px;">
        <p style="font-size:14px;color:#6b7280;">Growth</p>
        <p style="font-size:48px;font-weight:700;color:#16a34a;">${quarter.growth}%</p>
      </div>
    </div>
  </section>
`).join("\n");

const resp = await fetch("/api/export/jobs", {
  method: "POST",
  headers: { "Authorization": "Bearer sk_live_xxxx", "Content-Type": "application/json" },
  body: JSON.stringify({ fileName: "q-report.pptx", html: slides }),
});
```

### Sales Proposal Templates

Define brand-compliant slide templates in HTML/CSS once, then populate them with dynamic content for each campaign or client pitch. Variables like company name, project details, and pricing are injected at generation time. Marketing teams maintain the templates; sales reps get pixel-perfect branded decks instantly.

```javascript
// Sales proposal template with dynamic client data
function generateProposal(client) {
  return `
    <section class="slide" style="width:1600px;height:900px;padding:60px;background:linear-gradient(135deg,#1a1a2e,#16213e);">
      <h1 style="color:#fff;font-size:48px;">${client.companyName} 御中</h1>
      <p style="color:#a0aec0;font-size:24px;margin-top:20px;">ご提案書 - ${client.projectName}</p>
      <div style="position:absolute;bottom:60px;left:60px;color:#718096;font-size:14px;">
        ${new Date().toLocaleDateString('ja-JP')} | Confidential
      </div>
    </section>
    <section class="slide" style="width:1600px;height:900px;padding:60px;">
      <h2 style="font-size:36px;color:#1a1a2e;">提案概要</h2>
      <div style="display:grid;grid-template-columns:1fr 1fr 1fr;gap:30px;margin-top:40px;">
        ${client.features.map(f => `
          <div style="background:#f7fafc;border-radius:12px;padding:24px;">
            <h3 style="font-size:20px;color:#2d3748;">${f.title}</h3>
            <p style="font-size:14px;color:#718096;margin-top:8px;">${f.description}</p>
          </div>
        `).join('')}
      </div>
    </section>
  `;
}
```

### Agent-Powered Presentations

Let AI agents create presentation decks from meeting notes, research summaries, or project briefs. Using Skills or MCP integration, the agent understands the html2pptx.app HTML contract, generates compliant slides, and delivers a download link. Users simply describe what they want in natural language.

### SaaS Export Embedding

Add "Export to PowerPoint" functionality to your SaaS product. Render your app's dashboards, analytics views, or reports as slide HTML and call the html2pptx.app API from your backend. Users get native PPTX files with editable text and shapes -- not flat screenshots.

```javascript
// Backend route: POST /api/dashboard/export-pptx
app.post("/api/dashboard/export-pptx", async (req, res) => {
  const { dashboardId } = req.body;
  const dashboard = await getDashboard(dashboardId);

  // Render each widget as a slide
  const slides = dashboard.widgets.map(widget => `
    <section class="slide" style="width:1600px;height:900px;padding:40px;">
      <h2 style="font-size:28px;color:#1a1a2e;">${widget.title}</h2>
      <div style="margin-top:20px;">${widget.renderToHTML()}</div>
    </section>
  `).join("");

  // Call html2pptx.app API
  const job = await fetch(process.env.HTML2PPTX_API_URL + "/api/export/jobs", {
    method: "POST",
    headers: {
      "Authorization": `Bearer ${process.env.HTML2PPTX_API_KEY}`,
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      fileName: `${dashboard.name}.pptx`,
      html: slides,
    }),
  });

  const { jobId } = await job.json();
  res.json({ jobId, statusUrl: `/api/export/jobs/${jobId}` });
});
```

---

## Plans & Pricing

Choose the plan that fits your usage. The current public catalog is defined in code and enforced in the API gateway: requests per minute, daily guardrails, maximum slides per job, concurrent jobs, API key count, and payload size all vary by plan.

| Plan | Exports | Slides/Job | Support | Price |
|------|---------|-----------|---------|-------|
| Free Preview | 10 per month / 3 rpm | 20 per job | Community | ¥0 |
| Founder Beta | 300 per month / 5 rpm | 50 per job | Self-serve | ¥980/mo |
| Starter | 3,000 per month / 15 rpm | 100 per job | Email | ¥2,980/mo |
| Business | 20,000 per month / 60 rpm | 200 per job | Priority | ¥9,800/mo |
| Enterprise / OEM | Custom | 500+ per job | Dedicated | ¥49,800/mo〜 |

Upgrade anytime from the Dashboard. Changes take effect immediately with prorated billing. Downgrade at the end of the current billing period.

---

## Security & Limits

Public API, Skills, MCP, Studio, and hosted web export are all routed through the same security-sensitive conversion pipeline. The practical controls below are the ones that matter when you integrate or expose the product.

### Authentication and authorization

REST API uses API keys. Remote MCP supports commercial API keys or WorkOS-backed authenticated sessions. Job lookup is bound to the same API key or authenticated principal that created the job.

### SVG and untrusted markup

Public API and MCP sanitize incoming HTML. Inline SVG is converted to PNG images for reliable output.

### Worker isolation

Export jobs run in isolated contexts with enforced request body limits and automatic cleanup of expired jobs.

### Usage controls

Per-minute rate limiting, daily guardrails, monthly fair-use review thresholds, maximum slides per job, maximum payload size, and concurrent job limits are all enforced server-side based on the active plan.

### Recommended production practices

- Treat API keys as secrets and rotate them from the dashboard when they are exposed.
- Use the REST API for backend automation and same-origin hosted web export only for first-party browser flows.
- Poll the public job status route with backoff instead of hammering the status endpoint.
- Keep slide markup deterministic: explicit slide dimensions, predictable CSS, and no runtime-dependent content. 1600x900 remains the default example.
- With responseFormat: "base64", fileBase64 can be large; decode it in streaming or binary-safe code paths on your side.
- For agent integrations, decide whether the client should use local stdio MCP or remote /mcp before rollout.

---

## FAQ

### How is html2pptx.app different from other HTML-to-PPTX solutions?

Most alternatives take a screenshot of your HTML and embed it as a flat image in each slide. html2pptx.app produces fully editable PowerPoint output -- CSS properties like flexbox, gradients, border-radius, and shadows are faithfully reproduced. The result is editable text, high-quality shapes, and smaller file sizes.

### Can I convert any HTML to PPTX?

Not reliably. html2pptx.app is optimized for slide-oriented HTML with .slide class elements and explicit dimensions. 1600x900 is the default example, but portrait and other custom sizes are also supported. Arbitrary web pages, interactive apps, scroll-based layouts, and pages with JavaScript-dependent rendering are not supported. The HTML contract section describes the exact requirements.

### What becomes a separate slide?

Each element with the .slide class becomes one slide in the output PPTX. If your HTML contains 5 elements with class="slide", the output will have 5 slides. Define clear slide boundaries for predictable results.

### Will exported content remain editable in PowerPoint?

Yes, in most cases. Text stays fully editable and shapes remain adjustable in PowerPoint. Inline SVG is converted to high-quality PNG images for reliable output.

### How long does export take?

Most single-slide jobs complete in 3-5 seconds. Multi-slide decks (10-50 slides) typically take 8-20 seconds depending on complexity, image count, and font embedding. The worker processes slides in parallel where possible. Poll the job status endpoint every 2 seconds for optimal responsiveness.

### Which fonts are supported?

System fonts (Arial, Helvetica, Times New Roman, etc.) work by default. For web fonts, enable autoEmbedFonts: true -- html2pptx.app will download the font files from Google Fonts or your custom @font-face URLs and embed them into the PPTX. Japanese fonts like Noto Sans JP, Yu Gothic, Meiryo, and Hiragino are fully supported.

### Is there a free plan?

Yes. The current public catalog includes an Early Access tier with limited API, Skills, and MCP usage. Check GET /api/export/plans for the current plan metadata because limits are enforced from code and may evolve during early rollout.

### Can I use SVGs in my slides?

Yes. Inline SVG is supported and is converted to high-quality PNG images for reliable output across all PowerPoint environments.

### What is the maximum file size?

The HTML payload should stay under 5MB. Generated PPTX files vary by content but typically range from 100KB to 10MB. Jobs with many high-resolution images embedded as base64 will produce larger files. Consider using URL references for large images.

### How secure is the service?

html2pptx.app implements multiple security layers: jobs are bound to the creating principal; API keys are hashed at rest; request body limits and concurrent job limits are enforced server-side. Use the REST API for server-side automation and treat hosted web export as a browser surface.

### Does html2pptx.app support Japanese text and CJK characters?

Yes, fully. Japanese, Chinese, and Korean characters render correctly. For best results, specify a CJK font in your CSS (e.g., font-family: "Noto Sans JP", sans-serif) and enable autoEmbedFonts to ensure portable rendering on machines without the font installed.

### How do I handle errors?

Check the job status endpoint. If status is "failed", the error field contains a human-readable description. All API errors return a structured JSON body following RFC 9457 Problem Details format with type, status, title, detail, and instance fields, plus legacy error and message fields for backwards compatibility. Common issues: missing .slide elements (400), expired API key (401), rate limit exceeded (429), oversized content (413).

### Can I use CSS Grid for complex slide layouts?

Yes. CSS Grid is fully supported including grid-template-columns, grid-template-rows, gap, and grid placement properties. This makes it easy to create multi-column layouts, dashboard-style cards, and complex visual arrangements that convert cleanly to PPTX.

### Is there a webhook for job completion?

Yes. Add a callbackUrl field (HTTPS only) to your POST /api/export/jobs request. The worker will POST the full job result to your callback URL when the job completes or fails, with an x-signature-sha256 HMAC header for verification. Alternatively, you can still use polling on GET /api/export/jobs/{jobId} with a 2-second interval. For MCP users, html2pptx_wait_for_export_job handles polling automatically.

---

## Troubleshooting

| Issue | Solution |
|-------|----------|
| Job stuck in "queued" status | The private worker may be offline or overloaded. Wait 30 seconds and retry. If persistent, check worker health from the Dashboard or contact support. |
| Slides appear blank | Ensure your HTML contains elements with class="slide" and that those elements have visible content. Also verify that CSS is included in the payload and not relying on external stylesheets. |
| Fonts look different in PPTX | Enable autoEmbedFonts: true to embed web fonts. If using custom fonts, ensure the @font-face URLs are publicly accessible. Fallback to system-safe fonts like Arial or Noto Sans for maximum compatibility. |
| 429 Rate limit error | Check the X-RateLimit-Reset header for when your window resets. Implement exponential backoff in your polling logic. Upgrade your plan for higher request limits. |
| Layout differs from browser preview | Use explicit dimensions on .slide elements with inline styles. 1600x900 is the default example, but custom aspect ratios also work when your slide HTML and requested width/height/layout match. Avoid responsive/percentage-based layouts, media queries, and viewport-relative units (vh, vw). |
| Images not appearing in PPTX | Use absolute URLs (https://...) or base64 data URIs for images. Relative paths and localhost URLs will fail. Ensure image URLs are publicly accessible from the worker. |
| PPTX file size is too large | Large files are usually caused by embedded base64 images or image-heavy content. Use URL references instead, or compress images before embedding. |

---

- Canonical docs: https://html2pptx.app/docs/en
- OpenAPI spec: https://html2pptx.app/api/openapi.json
- MCP endpoint: https://html2pptx.app/mcp
- Short llms.txt: https://html2pptx.app/llms.txt

*Generated from html2pptx.app documentation. For the latest version, visit https://html2pptx.app/docs/en*