---
title: "List Historical Anomalies"
method: GET
path: "/1/signals/{signalId}/historical_anomalies"
tags: ["Anomaly Detection"]
---

# List Historical Anomalies

`GET /1/signals/{signalId}/historical_anomalies`

## Request

- Base URL: `https://api.honeycomb.io`
- URL: `https://api.honeycomb.io/1/signals/{signalId}/historical_anomalies`
- Auth: API key in header `X-Honeycomb-Team`

List anomalies that a Signal has resolved within a bounded time window. Anomalies are returned in cursor-paginated pages, most recent first. `start_time` and `end_time` are required and must span no more than 30 days.

## Query parameters

- `start_time` integer, required
- `end_time` integer, required
- `page[after]` string
- `page[size]` number

## Response `200`

Success

- PaginatedHistoricalAnomaliesResponse: A page of resolved historical anomalies for a Signal.
  - `historical_anomalies` HistoricalAnomaly[], required: The anomalies in this page, most recent first.
    - `id` string, required: A deterministic identifier for the anomaly, derived from the Signal, its measured kind, and the anomaly's start time.
    - `started_at` integer, required: The time the anomaly started, in seconds since UNIX epoch.
    - `ended_at` integer, required: The time the anomaly ended, in seconds since UNIX epoch.
    - `measurement` number, required: The measured value that triggered the anomaly.
    - `normal_range` HistoricalAnomalyNormalRange, required: The trained normal band a measurement exceeded.
      - `lower` number, required: The lower bound of the trained normal band.
      - `upper` number, required: The upper bound of the trained normal band.
  - `links` PaginationLinks: Links to iterate through the pages of results.
    - `next` string, nullable, required: The URL for the next page of results.

## Other responses

- `400`: The provided request body was invalid.
- `401`: Unauthorized
- `403`: Forbidden
- `404`: Not Found
- `422`: Validation Failed
- `429`: Rate Limit Exceeded
- `default`: Error

## Changes

- **2026-11-03** `276c5555582a`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/honeycomb/apis/honeycomb-api/changes/1/signals/:signalId/historical_anomalies/get.md)

---

[API](https://skmtc.dev/honeycomb/apis/honeycomb-api.md) - [All operations](https://skmtc.dev/honeycomb/apis/honeycomb-api/llms.txt) - [OpenAPI document](https://skmtc.dev/honeycomb/apis/honeycomb-api/revisions/276c5555582a?raw)