Streaming Resume broken on Interactions API - Deep Research often cannot resume

Gemini API
1

We have been launching deep-research-preview-04-2026 agents on the Interactions API since their launch a week or so ago.

Starting yesterday we are NOT able to “streaming resume” many of the runs. This happens in particular with the deep-research-preview-04-2026 (NON MAX) version, for inputs as simple as just say `hi` .

What happens:

  1. We POST to Interactions a request for deep-research-preview-04-2026 with background=true, stream=true, store=true
  2. The response starts coming, mostly an Event Stream of thought_summary blocks
  3. After fewer than 10 events, the connection may stop, either aborted by the client, or terminated by the Gemini server (see related bug about Interactions breaking at the 10-minute mark)
  4. We reconnect to the Interaction ID to replay the events and reattach to the stream
  5. ONLY THE FIRST 2 EVENTS ARE REPLAYED
  6. The REQUEST IS NOW STUCJ - the connection keeps active but nothing else will come up

Example:

1. POST /interactions → create & stream:

curl 'https://generativelanguage.googleapis.com/v1beta/interactions?key=XXX' \
  -H 'content-type: application/json' \
  --data-raw '{"agent":"deep-research-preview-04-2026","input":"just say hi","stream":true,"background":true,"store":true,"agent_config":{"type":"deep-research","thinking_summaries":"auto"}}'

Response:

event: interaction.start
data: {"interaction":{"id":"[ID]","status":"in_progress","object":"interaction","agent":"deep-research-preview-04-2026"},"event_type":"interaction.start"}

event: interaction.status_update
data: {"interaction_id":"[ID]","status":"in_progress","event_type":"interaction.status_update"}

event: content.start
data: {"index":0,"content":{"type":"thought"},"event_type":"content.start"}

event: content.delta
data: {"index":0,"delta":{"content":{"text":"[...]","type":"text"},"type":"thought_summary"},"event_id":"[ID]","event_type":"content.delta"}

event: content.delta
data: {"index":0,"delta":{"content":{"text":"[...]","type":"text"},"type":"thought_summary"},"event_type":"content.delta"}

event: content.delta
data: {"index":0,"delta":{"content":{"text":"[...]","type":"text"},"type":"thought_summary"},"event_type":"content.delta"}

2. GET /interactions/{id} → reattach:

curl 'https://generativelanguage.googleapis.com/v1beta/interactions/[ID]?key=XXX&stream=true' \
  -H 'content-type: application/json'

event: interaction.start
data: {"interaction":{"id":"[ID]","status":"in_progress","object":"interaction","agent":"deep-research-preview-04-2026"},"event_type":"interaction.start"}

event: interaction.status_update
data: {"interaction_id":"[ID]","status":"in_progress","event_type":"interaction.status_update"}

ONLY 2 EVENTS ARE SHOWN, the connection STAYS OPEN even for a day, and nothing ever arrives anymore.

Reattaching to an in-progress interaction consistently replays only the first 2 events and then stalls indefinitely, making it impossible to reliably consume long-running deep research results.