> For the complete documentation index, see [llms.txt](https://docs.pandium.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.pandium.com/getting-started/anatomy-of-an-integration/environment-variables/stderr.md).

# Logging (StdErr)

Log integration messages to stderr in Pandium so users can view run output and errors in the Integration Hub and In-App Marketplace across integrations and tenants.

All logs that you wish to display to your users should be written to `stderr.`

These logs can be viewed via the In-App Marketplace by users, or from within the Integration Hub on various pages, including the integration level, tenant level, and main run resource.

Below are various examples of how to do this is in multiple languages.

{% tabs %}
{% tab title="C#" %}

```
using System;

Console.Error.WriteLine("Hello World")
```

{% endtab %}

{% tab title="Java" %}

```java
System.err.println("Hello World!");
```

{% endtab %}

{% tab title="NodeJS" %}

```
console.error('Hello World')
```

{% endtab %}

{% tab title="PHP" %}

```php
fwrite(STDERR, 'Hello World' . PHP_EOL);
```

{% endtab %}

{% tab title="Python" %}

```python
import sys

print("Hello World!", file=sys.stderr)
```

{% endtab %}

{% tab title="Ruby" %}

```ruby
require "logger"

log = Logger.new(STDERR)

log.debug('Hello Word!')
```

{% endtab %}
{% endtabs %}


---

# 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 by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.pandium.com/getting-started/anatomy-of-an-integration/environment-variables/stderr.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

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.