Gemini API ships Webhooks and field-level Interactions errors

• Google shipped Gemini API webhooks, which OfficialLoganK's launch post framed as a fix for long-running batch, agent, and media jobs that previously needed status polling.
• Google also upgraded Interactions API validation errors, and _philschmid's breakdown says the responses now name the exact field, quote the bad value, list valid enums, and show expected versus actual types.
• The official Webhooks docs say the feature works across Batch jobs, Interactions, and video generation, with both project-wide static endpoints and per-request dynamic webhook URLs.
• The official Interactions API guide positions the API as Google's beta unified interface for models and agents, with stored interaction state and background execution, which makes clearer field-level errors more useful than they would be on a single stateless call.

Google's own launch post says some Gemini operations can run for up to two hours or more, which is why the polling fix landed now. You can also browse the webhook docs for secret rotation and signature verification details, and the Interactions API guide makes clear this is the beta surface Google wants developers to use for stateful, tool-using agent runs.

According to OfficialLoganK's post, webhooks are aimed at the annoying part of long-running Gemini jobs: waiting on batch runs, agent tasks, and media generation without hammering GET /operations.

The official Webhooks docs say the new endpoint can fire for Batch jobs, Interactions, and video generation. Google split the feature into two routing models:

• Static webhooks, configured once at the project level
• Dynamic webhooks, passed per request for job-specific callbacks

Google's launch post describes the whole thing as a push-based replacement for polling on operations that may take hours.

The other ship was smaller, but probably the one developers feel first. _philschmid's summary says Interactions API errors now expose four pieces of debugging detail that were easy to miss before:

• The exact field path, such as input[0].name
• The rejected value itself
• The full set of supported enum values when an enum is wrong
• Expected versus actual type format on mismatches

That lines up with what the Interactions API guide is trying to be: a beta interface for stateful conversations, tool orchestration, and background execution. On an agent run with nested request payloads, a field path is worth more than a generic 400.

The docs add a few implementation details that did not fit in the launch tweets. In the official Webhooks guide, Google says webhook deliveries use HTTP POST, require a 2xx response within a few seconds, and retry failed deliveries for 24 hours with exponential backoff.

The same guide says Gemini follows the Standard Webhooks spec, returns the signing secret only once at creation time, and supports secret rotation with either immediate revocation or a 24-hour grace period. The JavaScript example also notes that handlers should read the raw request body, not express.json(), because signature verification depends on the untouched payload.