Developer assessment/setup MCP; admitted Once boundaries protect writes, not sibling connectors.
Connect Runs on your machine
claude mcp add once -e ONCE_API_KEY=<ONCE_API_KEY> -- npx -y @once-agent/[email protected]{
"mcpServers": {
"once": {
"command": "npx",
"args": [
"-y",
"@once-agent/[email protected]"
],
"env": {
"ONCE_API_KEY": "<ONCE_API_KEY>"
}
}
}
}{
"mcpServers": {
"once": {
"command": "npx",
"args": [
"-y",
"@once-agent/[email protected]"
],
"env": {
"ONCE_API_KEY": "<ONCE_API_KEY>"
}
}
}
}{
"servers": {
"once": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@once-agent/[email protected]"
],
"env": {
"ONCE_API_KEY": "<ONCE_API_KEY>"
}
}
}
}Replace the values in angle brackets with your own. Keys stay on your machine; we never see them.
Tools
This server runs locally, so its tools are listed by your MCP client once it starts.
Environment variables
| Name | Description |
|---|---|
ONCE_API_KEYOptional, secret | Optional key for Cloud checks. Without it once_verify_connection reports Cloud unconfigured/unverified and preserves local diagnostics. |
Details
| Package | @once-agent/[email protected] (NPM, stdio) |
| First published | 8 Oct 2026 |
| Last updated | 8 Oct 2026 |
| Registry name | io.github.stringsofthemind-oss/once |
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