# Starburst: Major incident: Galaxy MCP server — tool calls failing

> Major incident: Galaxy MCP server — tool calls failing. Detected 2026-11-04 by Rewindex: what changed on Starburst’s status page, with the before/after diff.

Canonical: https://rewindex.com/change/i08bc1a3f3bbd2a
Last updated: 2026-11-04T08:23:50Z

**Summary:** _summary pending_
- Kind: Major incident · Label: outage (model (Jev))
- Changed: 2026-09-09 20:42 UTC · Detected: 2026-11-04 08:23 UTC
- [Source: https://status.galaxy.starburst.io/incidents/njw44gcf8474](https://status.galaxy.starburst.io/incidents/njw44gcf8474)
- [Company: Starburst](https://rewindex.com/company/starburst.md)
- Versions: before (none: first archived) → after incident\_version:165/njw44gcf8474@e38ffed2f7b7
- Change 1 of 1 for this incident

Incident page (full timeline): [Galaxy MCP server — tool calls failing](https://rewindex.com/company/starburst/incidents/njw44gcf8474.md)
## What changed

**1. Added: Title**

```diff
+ Galaxy MCP server — tool calls failing
```

**2. Added: Impact**

```diff
+ major
```

**3. Added: Status**

```diff
+ resolved
```

**4. Added: Start time**

```diff
+ 2026-09-09 20:42 UTC
```

**5. Added: Resolved time**

```diff
+ 2026-09-09 20:42 UTC
```

**6. Added: Affected components**

```diff
+ Starburst Galaxy UI
```

**7. Added: Update** (identified) · 2026-09-09 12:02 UTC

```diff
+ Starburst Galaxy's MCP server is returning an error for every tool call from MCP clients using the newest protocol revision, 2026-07-28. Sign-in, discovery and tool listing are unaffected, and clients on revision 2025-11-25 are not affected. Workaround: pin your MCP client to protocol revision 2025-11-25, which has been confirmed to restore tool calls. We are investigating and will post an update as soon as we have one.
```

**8. Added: Update** (identified) · 2026-09-09 14:37 UTC

```diff
+ We've identified an issue causing MCP tool calls to fail with a protocol error for Galaxy MCP users (both mcp-starburst and mcp-starburst-public, all auth methods). A fix is in progress. Workaround (Claude Code users): setting "MCP_PROTOCOL_NEGOTIATION": "legacy" in ~/.claude/settings.json mitigates the issue. Other MCP clients (Gemini CLI, Cursor, Continue.dev, Cline) aren't currently affected, since they default to an older protocol revision.
```

**9. Added: Update** (resolved) · 2026-09-09 20:42 UTC

```diff
+ This incident is now resolved. All impacted MCP calls should now be operating as expected.
```

## History of this incident

| When (UTC) | Change | Label |
| --- | --- | --- |
| 2026-09-09 20:42 UTC | Major incident: Galaxy MCP server — tool calls failing (this change) | outage |

All Starburst changes: [timeline](https://rewindex.com/company/starburst/changes.md)
_Diff excerpts are shown on normalized text: dates, counters and tokens appear as ‹date›, ‹count›, ‹tok›; noise-only edits are hidden. Rewindex shows the changed passages, not a copy of the page._

## Cite this

Major incident: Galaxy MCP server — tool calls failing on Starburst’s status page, changed 2026-09-09 20:42 UTC (change 1 of 1).

- Canonical URL: https://rewindex.com/change/i08bc1a3f3bbd2a
- Citation: Starburst, “Major incident: Galaxy MCP server — tool calls failing” (2026-09-09 20:42 UTC). Archived by Rewindex: https://rewindex.com/change/i08bc1a3f3bbd2a (CC BY 4.0).
- Markdown link: `[Starburst: Major incident: Galaxy MCP server — tool calls failing (2026-09-09)](https://rewindex.com/change/i08bc1a3f3bbd2a)`


---
Canonical: https://rewindex.com/change/i08bc1a3f3bbd2a · Markdown: https://rewindex.com/change/i08bc1a3f3bbd2a.md · JSON: https://rewindex.com/api/v1/changes/i08bc1a3f3bbd2a · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-11-04T14:31:58.930Z