Circleback vs Proton Safe MCP
Circleback is a plugin bundle for AI coding tools published by Cursor. Marketplaces we read that list it: 1 (Cursor: cursor/plugins). Proton Safe MCP is an MCP server published by fbossiere. Marketplaces we read that list it: 2 (Official MCP Registry, Community GitHub marketplaces). As of our marketplace pass on 2026-10-15. This pair was picked by a reader, not by our comparison rule, so search engines are asked not to index the page.
Where each is published
| Marketplace |  Proton Safe MCP | |
|---|---|---|
| Cursor: cursor/plugins | Listed Version: 1.0.0 Forks (GitHub): 1 107 Stars (GitHub): 11 352 Not marked · First seen |
Not listed |
| Official MCP Registry | Not listed | Listed Version: 2.3.1 Downloads/month (PyPI): 1 085 Downloads/week (PyPI): 63 Forks (GitHub): 0 Stars (GitHub): 5 Not marked · First seen |
Each figure is the marketplace's own and is never added up across marketplaces. A marketplace that publishes no figure shows none: no number is not zero.
The facts side by side
| Fact | Circleback | Proton Safe MCP |
|---|---|---|
| Marketplaces that list it (differs) | 1 (worse) | 2 (better) |
| Stars (GitHub) (differs) | 11 352 (better) | 5 (worse) |
| Forks (GitHub) (differs) | 1 107 (better) | 0 (worse) |
| Last release (differs) | Not published | 2026-10-15 |
| Where it runs (differs) | Remote server (circleback.ai/api/mcp) | On your machine (proton-safe-mcp) |
| Transport (differs) | Streamable HTTP | stdio |
| Tools it declares | Not published | Not published |
| Environment variables it asks for (differs) | Not published | 2, secrets among them: 0 |
| Parts of the bundle (differs) | 1 | 4 |
| Licence | MIT | MIT |
| Repository (differs) | github.com/cursor/plugins | github.com/fbossiere/proton-safe-mcp |
| Changes in the last 7 days (differs) | 0 | 4 |
| First seen | 2026-10-11 | 2026-10-11 |
| Endpoint at the last check (differs) | not checked yet | no remote endpoint we check |
Lines where the two differ have a tinted background and bold values. Where the data itself says which value is better (more marketplaces, a larger figure of the same marketplace, a fresher release, a verified mark on a marketplace that lists both), the better one is also marked green with ▲ and the worse one red with ▼. Where it runs, the transport, the tools, the settings, hooks, the bundle's parts, the licence and the week's changes are marked only as different: more or fewer is not better in itself.
What each says it does
Circleback
Search meetings, transcripts, action items, and emails.
Proton Safe MCP
Read Proton Mail, extract bounded attachment text, and create explicitly confirmed drafts.
How to run each
Circleback
No data for an automatic command: what its marketplaces declare does not say unambiguously how to connect it.
Proton Safe MCP As a local MCP server: PyPI package
claude mcp add --env "PROTON_BRIDGE_USER=<YOUR_PROTON_BRIDGE_USER>" --transport stdio proton-safe-mcp -- uvx proton-safe-mcp serveRequires: PROTON_BRIDGE_USER
Commands built only from what the marketplaces declare; the full set for every client is on each card.
Tools each declares
Neither one's marketplaces publish a list of tools, so there is nothing to compare.
Settings each asks for
The marketplaces of Circleback publish no settings it asks for, so we do not compare settings.
What it can do: Circleback · What it can do: Proton Safe MCP · Compare two other plugins
Data comes from the public marketplace file https://github.com/cursor/plugins/blob/HEAD/.cursor-plugin/marketplace.json. Data comes from the Official MCP Registry (registry.modelcontextprotocol.io), CC0 1.0. Data comes from public marketplace files in GitHub repositories of their authors. Figures come from our own regular passes over the marketplaces, last read on . We publish no contact details for plugin publishers.