mastra-ai/mastra · error · HTTPException

Cannot delete the active version. Activate a different versi

Error message

Cannot delete the active version. Activate a different version first.

What it means

The delete-version route refuses (HTTP 400) to delete the version that the MCP client currently has active (mcpClient.activeVersionId === versionId). This guards against leaving the client without a usable active configuration.

Source

Thrown at packages/server/src/server/handlers/mcp-client-versions.ts:414

      const mcpClient = await mcpClientStore.getById(mcpClientId);
      if (!mcpClient) {
        throw new HTTPException(404, { message: `MCP client with id ${mcpClientId} not found` });
      }
      assertStoredResourceScope(mcpClient, await getStoredResourceScope(mastra, requestContext));

      const version = await mcpClientStore.getVersion(versionId);
      if (!version) {
        throw new HTTPException(404, { message: `Version with id ${versionId} not found` });
      }
      if (version.mcpClientId !== mcpClientId) {
        throw new HTTPException(404, {
          message: `Version with id ${versionId} not found for MCP client ${mcpClientId}`,
        });
      }

      if (mcpClient.activeVersionId === versionId) {
        throw new HTTPException(400, {
          message: 'Cannot delete the active version. Activate a different version first.',
        });
      }

      await mcpClientStore.deleteVersion(versionId);

      // Clear the editor cache so subsequent requests see the updated config
      mastra.getEditor()?.mcp.clearCache(mcpClientId);

      return {
        success: true,
        message: `Version ${version.versionNumber} deleted successfully`,
      };
    } catch (error) {
      return handleError(error, 'Error deleting MCP client version');
    }
  },
});

View on GitHub (pinned to 75dd419e61)

Solutions

1. Activate a different version first (activate/restore endpoint), then delete this one.
2. Skip the active version in cleanup logic: check activeVersionId before deleting.
3. If the client is obsolete, delete the whole MCP client instead of its versions.

Example fix

// before
await deleteVersion(clientId, activeVersionId); // 400
// after
if (client.activeVersionId !== versionId) {
  await deleteVersion(clientId, versionId);
} else {
  await activateVersion(clientId, otherVersionId);
  await deleteVersion(clientId, versionId);
}

const client = await (await fetch(`/api/stored/mcp-clients/${clientId}`)).json();
if (client.activeVersionId === versionId) throw new Error('Refusing to delete the active version');

try { await del(); } catch (e) { if (e.status === 400 && /active version/.test(e.message)) await activateOtherThenDelete(); else throw e; }

When it happens

Trigger: DELETE /stored/mcp-clients/:mcpClientId/versions/:versionId where versionId equals the client's activeVersionId.

Common situations: Cleaning up old versions and indiscriminately including the active one; UI delete button not disabled for the active version; automated cleanup scripts without an active-version check.

Related errors

• Version with id ${input.id} already exists
• Version number ${input.versionNumber} already exists for MCP
• Cannot delete the active version. Activate a different versi
• bad request: ${responseText}
• DATASET_ITEM_NOT_FOUND

AI-assisted analysis of mastra-ai/mastra@75dd419e61 (2026-08-30). Data as JSON: /api/errors/f1f0a6d46062a4f7. Report an issue: GitHub.