opencode-websearch

Web search plugin for OpenCode, inspired by Claude Code's built-in web search. Gives any OpenCode model access to real-time web results with source citations.

Supported providers

| Provider | SDK package | Search mechanism | | --------- | ------------------- | -------------------------------------------------------------------------------------------------- | | Anthropic | @ai-sdk/anthropic | web_search tool | | OpenAI | @ai-sdk/openai | Responses API web search |

Install

Add the plugin to your opencode.json:

{
  "plugin": ["opencode-websearch"]
}

OpenCode will install it automatically at startup.

Configuration (optional)

No configuration is needed if your active chat model belongs to a supported provider. To customize which model handles web searches, tag a model with "websearch": "auto" or "websearch": "always".

Model selection

The plugin chooses which model to use for each search:

| Priority | Condition | Behavior | | -------- | ---------------------------------------------- | ------------------------------------------------------------------------- | | 1 | A model is tagged "always" | That model is always used, regardless of what you're chatting with | | 2 | Your active chat model is a supported provider | The active model is used directly -- no extra configuration needed | | 3 | A model is tagged "auto" | That model is used as a fallback when the active model is unsupported | | 4 | None of the above | An error is returned |

"auto" mode (recommended)

Use "auto" when you want web search to work seamlessly regardless of your active model. When your active model belongs to a supported provider, it's used directly; otherwise the tagged model kicks in as a fallback.

{
  "provider": {
    "anthropic": {
      "models": {
        "claude-sonnet-4-5": {
          "options": {
            "websearch": "auto"
          }
        }
      }
    }
  }
}

"always" mode

Use "always" to lock web search to a specific model, regardless of what you're chatting with.

{
  "provider": {
    "openai": {
      "models": {
        "gpt-5.2": {
          "options": {
            "websearch": "always"
          }
        }
      }
    }
  }
}

Development

Local Development

To develop or customize the plugin locally, clone the repo and symlink the source entry point into your OpenCode plugin directory:

git clone https://github.com/emilsvennesson/opencode-websearch ~/.config/opencode/opencode-websearch
cd ~/.config/opencode/opencode-websearch
bun install
mkdir -p ~/.config/opencode/plugin
ln -sf ~/.config/opencode/opencode-websearch/src/index.ts ~/.config/opencode/plugin/websearch.ts

OpenCode will load the plugin directly from source on startup. Any edits to the files in src/ take effect next time you start OpenCode.

Note: When using the symlink approach, remove "opencode-websearch" from the plugin array in your opencode.json to avoid loading the plugin twice.

Commands

bun install            # install dependencies
bun run format         # auto-format source files
bun run format:check   # verify formatting (no changes)
bun run lint           # run oxlint
bun run lint:fix       # auto-fix lint issues
bun run typecheck      # type check with tsc
bun run check          # format:check + lint + typecheck (full quality gate)
bun run build          # ESM bundle + declaration files → dist/

License

MIT