MCP Boundary

Tested Servers And Limits

MCP Boundary uses scoped evidence. A successful test of one tool does not become a broad provider-support claim.

The rule:

tools/list is discovery.
At least one real tools/call through MCP Boundary is runtime proof.

Current Evidence Summary

AreaStatusWhat it means
Local Email Demoverified local demoSimulated read/draft/send-block flow. No provider or real email.
Gmail-like local stdio serverscoped runtime proofDownstream-managed OAuth path proved read metadata, controlled draft, controlled send, and selected controlled label/archive/trash actions for configured candidates.
Taylor Google Workspace candidatescoped candidate proofDownstream-managed stdio OAuth path proved selected Gmail read/draft/send/trash-label actions. Not a full Workspace claim.
Official Gmail MCP endpointprovider blockedOAuth and tools/list worked, but real tool execution was blocked by provider permission.
Database examplesscoped smokeUseful for read/write policy examples and state binding with synthetic data.
GitHub test reposcoped smokeUseful for selected repo/test-account behavior. Not full GitHub support.
Microsoft 365 / Outlooksetup dependentDiscovery/auth setup depends on Graph app setup, account type, tenant, and permissions.

Safe Claims

Good:

MCP Boundary can run a configured local MCP server through a checked tool-call path.

Good:

A configured downstream-managed local Gmail-like MCP server has scoped read,
draft, send, and selected label/archive/trash evidence.

Bad:

MCP Boundary supports Gmail.

Bad:

MCP Boundary makes email safe.

Not Claimed

MCP Boundary does not claim:

  • production security
  • DLP
  • prompt-injection protection
  • universal provider support
  • safe-by-default sending or deletion
  • full Google Workspace / Gmail / Outlook / GitHub / database support
  • hosted multi-tenant gateway behavior

Use the full evidence document for details:

  • docs/publish/tested-servers-and-limits.md