fix(datadog): compare downtime targets after parsing, not before

A whitespace-only Monitor ID is truthy as a raw string but parses to no monitor, so
the oneOf conflict guard rejected a valid tag-targeted downtime whenever the untouched
Monitor ID field carried blank text. Both sides are now compared after parsing.

Author: waleedlatif1

apps/sim/tools/datadog/create_downtime.ts

@@ -102,20 +102,21 @@ export const createDowntimeTool: ToolConfig<CreateDowntimeParams, CreateDowntime
       if (params.end) schedule.end = new Date(params.end * 1000).toISOString()
 
       const monitorTags = splitCommaList(params.monitorTags)
+      const monitorId = parseMonitorIds(params.monitorId)?.[0]
 
       /**
        * `monitor_identifier` is required and is a `oneOf`: a downtime targets either a
        * single monitor or a tag set, never both. Accepting both silently would drop one
-       * of them and mute a different set of monitors than the caller asked for.
+       * of them and mute a different set of monitors than the caller asked for. Both
+       * sides are compared after parsing so a blank or whitespace-only input, which is
+       * how an untouched field arrives, does not read as a chosen target.
        */
-      if (params.monitorId && monitorTags) {
+      if (monitorId !== undefined && monitorTags) {
         throw new Error(
           'Supply either a monitor ID or monitor tags, not both — a downtime targets one or the other'
         )
       }
 
-      const monitorId = parseMonitorIds(params.monitorId)?.[0]
-
       // Datadog expresses "every monitor in scope" as the `*` monitor tag, which is the
       // fallback when no monitor is named.
       const monitorIdentifier =

apps/sim/tools/datadog/datadog.test.ts

@@ -416,6 +416,17 @@ describe('create_downtime monitor targeting', () => {
     expect(body.data.attributes.monitor_identifier).toEqual({ monitor_id: 123 })
   })
 
+  /** A blank monitor ID is how an untouched field arrives; it is not a chosen target. */
+  it('does not treat a whitespace-only monitor id as a conflicting target', () => {
+    const body = callBody(createDowntimeTool, {
+      ...auth,
+      scope: '*',
+      monitorId: '   ',
+      monitorTags: 'team:backend',
+    } as any)
+    expect(body.data.attributes.monitor_identifier).toEqual({ monitor_tags: ['team:backend'] })
+  })
+
   it('accepts monitor tags that arrive as an array', () => {
     const body = callBody(createDowntimeTool, {
       ...auth,