---
updatedAt: 2026-08-12T00:10:37.000Z
agentTools:
  projectIndex: https://docs.atono.io/llms.txt
---

# SDK error codes

A reference to error codes that may appear in Atono SDK log events.

The SDK may also log error codes from the HTTP client or OpenFeature that aren’t listed on this page.

<br />

`CLIENT_ERROR`

An error caused by an invalid SDK configuration or by using the SDK incorrectly.

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`INVALID_KEY`

A type of `CLIENT_ERROR` that indicates the environment key is invalid. The SDK can’t communicate with Atono using the supplied key.

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`NOT_FOUND`

The SDK requested information that doesn’t exist. This can occur when:

* evaluating a feature flag that isn’t defined in the workspace
* attempting to determine a location from a private IP address

<br />

`SERVICE_ERROR`

An error occurred in the Atono service while processing a request from the SDK.

<br />

`SERVICE_TIMEOUT`

A request to Atono was started but stopped because it exceeded the HTTP timeout configured in the SDK.

For information on changing the timeout, see [SDK configuration](https://docs.atono.io/docs/sdk-configuration).

<br />

`SERVICE_UNREACHABLE`

The SDK couldn’t initiate a request because the Atono service was unavailable.