> For the complete documentation index, see [llms.txt](https://docs.tryterra.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tryterra.co/faq/help-topics/data-api-sdk/webhooks-dedup-and-sync-reliability/daily-payload-cumulative-overwrite-by-day.md).

# Why are daily step totals inconsistent across webhooks?

Daily payloads are a **running summary of the 24-hour period**, sent multiple times as new data arrives, each containing totals up to that point. **Always overwrite a given date with the latest payload you receive.**

For Apple Health, each daily webhook is an update or correction, not an increment:

* The first comes from the first device that syncs.
* Further updates arrive as other devices sync into HealthKit.
* The `total` value comes directly from HealthKit and matches the Apple Health app, while `step_samples` are produced by Terra's aggregation across sources and converge to the same daily total by end of day.

Discrepancies versus the app are usually multiple devices syncing or data still processing. If the final total for a closed day still differs from the app for that exact date, report it for investigation. See [receiving data updates](https://docs.tryterra.co/health-and-fitness-api/managing-user-health-data/receiving-data-updates) for more.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.tryterra.co/faq/help-topics/data-api-sdk/webhooks-dedup-and-sync-reliability/daily-payload-cumulative-overwrite-by-day.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.
