Free Claude Sonnet 4.5: OmniRoute + Node.js

Get Free Access to Claude Sonnet 4.5 via OmniRoute and Node.js 22

OmniRoute requires Node.js version 22 specifically, as newer releases don’t support the necessary dependencies. Install nvm to manage your Node versions.

Install nvm:

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.4/install.sh | bash

Add to ~/.zshrc or ~/.bashrc:

export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
[ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion"

Apply changes:

source ~/.zshrc

Install and activate Node.js 22:

nvm install 22
nvm alias default 22

Verify the version:

node -v

The output should be something like v22.x.x.

Install and Initialize OmniRoute

Globally install OmniRoute:

npm install -g omniroute

Create a config with a password:

mkdir -p ~/.omniroute
touch .env
echo -n $'\nINITIAL_PASSWORD=your_new_password\n' >> .env

Default password: 123456.

Run:

omniroute

Enter the password. A web dashboard will open by default.

Configure KiroAi Provider

In the OmniRoute dashboard, select KiroAi and click Configure Provider.

Choose AWS Builder ID. Sign in using your Google account and confirm permissions on AWS.

After authorization, available models—including Claude Sonnet 4.5—will appear in the provider list.

Go to Api Manager → Create your first key. Save the generated API key.

In Endpoints, copy the base URL: http://localhost:20128/v1.

Integrate with OpenCode

Install OpenCode:

npm i -g opencode-ai

Create or edit ~/.config/opencode/opencode.json:

{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "omni": {
      "name": "OmniRoute",
      "npm": "@ai-sdk/openai-compatible",
      "models": {
        "kr/claude-sonnet-4.5": {
          "name": "Omni sonnet-4.5"
        },
        "kr/claude-haiku-4.5": {
          "name": "Omni Haiku-4.5"
        }
      },
      "options": {
        "baseURL": "http://localhost:20128/v1"
      }
    }
  }
}

Copy the Model ID (kr/claude-sonnet-4.5) from the OmniRoute dashboard: http://localhost:20128/dashboard/providers/kiro.

Add your API key to ~/.local/share/opencode/auth.json:

{
  "omni": {
    "type": "api",
    "key": "sk-your-api-key"
  }
}

Run opencode and select the model using the /models command.

Setup Steps Summary

| Step | Action | Command/Action |

|------|--------|----------------|

| 1 | Install nvm | curl ... | bash |

| 2 | Node.js 22 | nvm install 22 |

| 3 | OmniRoute | npm install -g omniroute |

| 4 | Config .env | echo INITIAL_PASSWORD=... >> .env |

| 5 | Run | omniroute |

| 6 | Provider | AWS Builder ID via Google |

| 7 | API Key | Api Manager → Create key |

| 8 | OpenCode Config | ~/.config/opencode/opencode.json |

| 9 | Auth | ~/.local/share/opencode/auth.json |

Key Points

• Node.js Version: Only version 22 works—OmniRoute won’t start otherwise.
• API Key: The provider ID (omni) must match exactly in both opencode.json and auth.json.
• Base URL: Use http://localhost:20128/v1—this is the exact endpoint for OpenAI API compatibility.
• Authentication: Using AWS Builder ID via Google grants access to KiroAi models without needing a VPN.
• Model ID: Use kr/claude-sonnet-4.5 for Sonnet 4.5—verify it in the OmniRoute dashboard.

This method gives you local proxy access to high-end models without subscriptions or geo-restrictions. OmniRoute supports OpenAI-compatible APIs, making integration into existing workflows seamless.

— Editorial Team