Agent Config Adapter

---
name: stitch::upload-to-stitch
description: >-
  Upload local assets (images, mockups, extracted HTML) to a Stitch project.
  ALWAYS use this skill when you need to upload visual assets or full HTML pages
  to Stitch, particularly when direct MCP tool calls fail or truncate due to
  base64 token limits.
allowed-tools:
  - "stitch*:*"
  - "Bash"
  - "Read"
  - "Write"
  - "web_fetch"
---

# Upload-to-Stitch

Upload local assets (images, mockups, HTML files) to a Stitch project using the
provided upload script, which bypasses the MCP tool's base64 output token limits.

> [!NOTE]
> The AI model cannot upload files via MCP tools directly because the base64
> encoding of even a small file exceeds the model's output token limit (~16K
> tokens). This script reads the file and sends it directly over HTTP.

## Steps

### 1. Identify Target Project

Use `list_projects` to find the correct `projectId`.

### 2. Get the API Key

Locate your active MCP server configuration file and extract the API key:
- **Antigravity**: `.gemini/antigravity/mcp_config.json` or `.gemini/jetski/mcp_config.json`
- **Gemini CLI**: `~/.gemini/settings.json` or `~/.gemini/extensions/Stitch/gemini-extension.json`
- **Claude Code**: `~/.claude.json`

Extract:
- **API Key**: From the `X-Goog-Api-Key` header or auth argument
- **MCP URL** (optional): From the `httpUrl` or endpoint argument (defaults to
  `https://stitch.googleapis.com`)

> [!IMPORTANT]
> If you cannot find the API key in any of these locations, or if you cannot access these files, you MUST ask the user to provide the Stitch API key. Do not proceed without a valid API key.

### 3. Run Upload Script

> [!WARNING]
> **Checkpoint — User Confirmation Required.**
> Before running the upload script, you **MUST** pause and present the file(s)
> to be uploaded (paths, sizes, and types) to the user and wait for explicit
> approval. Do **NOT** execute the upload script until the user confirms.

Use `run_command` to execute the Python script:

```bash
python3 <SKILL_DIR>/scripts/upload_to_stitch.py \
  --project-id <PROJECT_ID> \
  --file-path <PATH_TO_FILE> \
  --api-key <API_KEY> \
  [--api-url <STITCH_API_URL>] \
  [--title <SCREEN_TITLE>]
```

> [!TIP]
> **macOS / SSL Certificate Troubleshooting:**
> If the upload fails with `ssl.SSLCertVerificationError: [SSL: CERTIFICATE_VERIFY_FAILED] unable to get local issuer certificate`, this means your Python installation does not have root certificate authorities configured.
> Fix it by prepending `SSL_CERT_FILE` using the `certifi` bundle:
> ```bash
> SSL_CERT_FILE=$(python3 -c "import certifi; print(certifi.where())") python3 <SKILL_DIR>/scripts/upload_to_stitch.py \
>   --project-id <PROJECT_ID> \
>   --file-path <PATH_TO_FILE> \
>   --api-key <API_KEY>
> ```

### Supported File Types

| Extension | MIME Type |
|:---|:---|
| `.png` | `image/png` |
| `.jpg`, `.jpeg` | `image/jpeg` |
| `.webp` | `image/webp` |
| `.html`, `.htm` | `text/html` |

The script auto-detects MIME type from the file extension.

### Script Defaults

- `--api-url` defaults to `https://stitch.googleapis.com`
- `--api-key` is **required**
- Screen instances are automatically created for display
- For HTML files, `screenType` is set to `DOCUMENT`; for images, `IMAGE`

Companion Files