ONCE
Rank #13,850io.github.GSterlingPress/once
Stop duplicate AI-agent side effects with idempotency, postcondition checks, and durable receipts.
ONCE is a Model Context Protocol (MCP) server published by GSterlingPress. It ranks #13,850 of 115,460 servers tracked on MCP Toplist. ONCE is listed across 2 registries — Official MCP and Glama, with 1 tracked version. It was first listed on Aug 10, 2026 and most recently updated on Aug 10, 2026.
Ranks ahead of 101,610 of 115,460 servers on MCP Toplist.
Use ONCE
No credentials or required configuration declared — add it to your MCP client and go.
claude mcp add --transport http once https://optimistic-compassion-production.up.railway.app/mcp[mcp_servers.once]
url = "https://optimistic-compassion-production.up.railway.app/mcp"Add to ~/.codex/config.toml.
https://optimistic-compassion-production.up.railway.app/mcpSettings → Connectors → “Add custom connector”, then paste this URL.
{
"mcpServers": {
"once": {
"url": "https://optimistic-compassion-production.up.railway.app/mcp"
}
}
}Add to ~/.cursor/mcp.json (global) or .cursor/mcp.json (per project).
{
"servers": {
"once": {
"type": "http",
"url": "https://optimistic-compassion-production.up.railway.app/mcp"
}
}
}Save as .vscode/mcp.json in your workspace.
{
"mcpServers": {
"once": {
"serverUrl": "https://optimistic-compassion-production.up.railway.app/mcp"
}
}
}Add to ~/.codeium/windsurf/mcp_config.json.
{
"mcpServers": {
"once": {
"url": "https://optimistic-compassion-production.up.railway.app/mcp"
}
}
}Show your rank
Maintain this server? Add the live rank badge to your README — it updates automatically as the leaderboard changes.
[](https://mcptoplist.com/server/io.github.GSterlingPress%2Fonce)<a href="https://mcptoplist.com/server/io.github.GSterlingPress%2Fonce"><img src="https://mcptoplist.com/badge/io.github.GSterlingPress%2Fonce.svg" alt="MCP Toplist: Top 25% of 115,460" /></a>Variants: append ?metric=score or ?metric=stars to the image URL.
Listed on 2 registries
GSterlingPress
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Available versions (1)
| Version | Published |
|---|---|
| 0.6.0 | Aug 10, 2026 |
Frequently asked questions
- Who maintains ONCE?
- ONCE is maintained by GSterlingPress, which publishes 7 MCP servers (6 total versions) tracked on MCP Toplist.
- Is ONCE listed on the Official MCP Registry?
- Yes — ONCE is listed on the Official MCP Registry, alongside Glama.
- How many versions does ONCE have?
- MCP Toplist tracks 1 version of ONCE, most recently published on Aug 10, 2026.
- Where can I find the source code for ONCE?
- The source code for ONCE is hosted at github.com/GSterlingPress/once-api.