# opencode-metasearch2

[OpenCode](https://opencode.ai) plugin that adds a `web_search` tool powered by [metasearch2](https://github.com/mat-1/metasearch2) -- a fast meta-search engine that aggregates results from Google, Bing, Brave, and others. No API keys required.

## Credits

Built on [metasearch2](https://github.com/mat-1/metasearch2) by [mat-1](https://github.com/mat-1) -- an awesome open-source meta-search engine written in Rust. All the heavy lifting (search aggregation, ranking, deduplication) happens there.

## Quick start

```sh
npm install opencode-metasearch2
```

Add to your `opencode.json`:

```json
{
  "plugins": {
    "metasearch": "opencode-metasearch2"
  }
}
```

That's it. The plugin ships with pre-built binaries for macOS, Linux, and Windows -- no Rust toolchain needed. On first run it spawns metasearch2 locally and exposes a `web_search` tool to your agent.

## Tool

### `web_search`

Search the web using a local metasearch engine that aggregates results from Google, Bing, Brave, and others. Returns raw JSON with search results, featured snippets, direct answers, and infoboxes.

| Argument | Type | Default | Description |
|---|---|---|---|
| `query` | `string` | *(required)* | The search query |
| `type` | `"all" \| "images"` | `"all"` | `"all"` for web results, `"images"` for image search |

#### Web search response

```json
[{
  "search_results": [
    {
      "result": { "url": "https://...", "title": "...", "description": "..." },
      "engines": ["google", "bing", "brave"],
      "score": 1.55
    }
  ],
  "featured_snippet": {
    "url": "https://...", "title": "...", "description": "...", "engine": "google"
  },
  "answer": { "html": "42", "engine": "numbat" },
  "infobox": { "html": "<h2>...</h2>", "engine": "wikipedia" }
}]
```

All fields except `search_results` are optional -- they appear when metasearch2 finds a direct answer, featured snippet, or infobox (Wikipedia, GitHub, StackOverflow, MDN, docs.rs).

#### Image search response

```json
[{
  "image_results": [
    {
      "result": {
        "image_url": "https://...",
        "page_url": "https://...",
        "title": "...",
        "width": 1200,
        "height": 800
      },
      "engines": ["google", "bing"],
      "score": 1.5
    }
  ]
}]
```

## How it works

1. Locates or installs the `metasearch` binary
2. Writes a config to `~/.config/metasearch/config.toml` enabling the JSON API and image search
3. Spawns the binary as a child process
4. Polls until the HTTP API is healthy (up to 10s)
5. Exposes a `web_search` tool to your agent

The metasearch2 process is killed automatically when the session ends.

## Configuration

| Variable | Default | Description |
|---|---|---|
| `METASEARCH_BIN` | *(auto-resolved)* | Path to the metasearch2 binary |
| `METASEARCH_PORT` | `28019` | Port for the local HTTP API |
| `METASEARCH_AUTO_INSTALL` | `true` | Set to `false` to skip auto `cargo install` |
| `XDG_CONFIG_HOME` | `~/.config` | Base directory for the config file |

### Advanced: engine configuration

The plugin generates a default `~/.config/metasearch/config.toml` on first run. You can edit it to enable/disable engines, adjust ranking weights, or block domains:

```toml
api = true
bind = "0.0.0.0:28019"

[image_search]
enabled = true

[engines]
google_scholar = true       # enable (off by default)
marginalia = false          # disable

[engines.brave]
weight = 2.0               # boost Brave results

[urls.weight]
".quora.com" = 0            # hide Quora results
".pinterest.com" = 0        # hide Pinterest results
```

Available engines: `google` (default), `bing` (default), `brave` (default), `marginalia` (default), `google_scholar`, `rightdao`, `stract`, `yep`. See the [metasearch2 docs](https://github.com/mat-1/metasearch2) for all options.

## Binary resolution

The plugin checks for the binary in order:

1. `METASEARCH_BIN` environment variable
2. **Bundled platform package** (`@galelmalah/metasearch2-*`) -- installed automatically as an `optionalDependency`
3. `$CARGO_HOME/bin/metasearch` (default: `~/.cargo/bin/metasearch`)
4. `/tmp/metasearch2-build/bin/metasearch`
5. **Auto-install**: runs `cargo install metasearch` if none of the above exist

## Benchmark

```sh
npx tsx benchmark.ts       # 5 queries
npx tsx benchmark.ts 20    # 20 queries
```

Reports startup timing (binary resolution, config, spawn, health check) and per-query search latencies with min/max/avg/p50/p95.

## Development

```sh
git clone https://github.com/galElmalah/opencode-metasearch2.git
cd opencode-metasearch2
npm install
npm run build
npx tsx --test test.ts
```

## License

MIT