What is a charter and why it is relevant

In ET (Exploratory Testing) approach, we don't follow predefined steps and check for well-known expectactions. We also don't test in a random way.

While performing ET, we use our experience and knowledge to uncover new information. Exploring can be done at any moment, at any time, even without a specific explicit reason whatsoever.

Usually, however, exploratory testing starts due to a reason and around some feature or area.

To focus our exploration activities, we use a charter. By having a charter, we can focus our attention around a certain question or concern we want to address. This way, we will be able to explore in more depth and find information that othewise would be hard to depict.

Before coming up with a charter, reflect a bit about:

• What is/are my main goal/s for the testing session?
• Do I want to deepen knowledge about a very specific "thing" (e.g., feature, flow, behaviour) or do I have to want a more high-level overview?
• Will I be using specific resources, tools, or heuristics?
• Will I be focused on certain quality criteria attributes? (e.g., correctness, performance, accessibility)
• Do I want to focus my attention more around positive test scenarios or negative test scenarios?

In sum, Why am I going to do this session? What "exactly" will be looking at? Using what? .

The structure of a charter

There is a common format that works for most teams.

Adapted from Maaret Pyhäjärvi, Elisabeth Hendrickson

However, the charter doesn't have a strict structure; we can actually taylor it to our own needs.

Examples

Next, there are some examples of possible charters.

In this case, we have a high-level charter, to have an overview of the system.

We can also focus on a specific feature, or page, and around a specific concern/quality criteria (e.g., usability).

We can still be focused on a specific feature, or page, but aiming to test how it works for different contexts/environments (e.g., browsers).

Eventually, we may even having a more focused charter, for example, to depict problems around some specific processing. 

Our exploration can be focused on a certain feature/area (e.g., REST API endpoint) and we can explicitly enumerate a subset of items we wish to validate (e.g., operations).

Our exploration can be made around specific personas relevant for the context of our product.

Sometimes we're concerned about product consistency (e.g., in terms of layout, terminology, options, operations); we can have a charter for that.

Charters can be used for targeting specific testing types such as security testing, for example. We may want to focus our attention and concerns around specific features and ways of "attacking" them.

Tips

Start with broad and then go to specifics

Start with broad (i.e. more generic) charters and common usage scenarios to have a more general idea about the system under test.

Use and stay focused to the charter

While testing, we should stick with the charter; if we depict something a bit unrelated, we can take notes and then decide afterwards if we want to create a charter around that.

Enumerate items you know in advance that you want to cover

You may add a list of bullet points to your charter if you want to enumerate certain aspects you aim to test or subsets for your charter (e.g., operations, user profiles).

Don't detail too much

Avoid having long charters as eventually they will tend to become closer to test scripts and limit your exploration.

Include quality attributes you aim to test

Usually, it is a good idea to know in advance the quality attributes/aspects you will be focused on, so you can target your exploration around those.

Discuss the charters with the team

Provide visibility of what you aim to test. The team can give you feedback about areas or aspects they may consider relevant, among others.

Reuse the charter

Charters can be reused; the findings of sessions with the same charter can and will be mostly different each time a person uses them during a testing session. A charter can be reused by another colleague, a tester, or even a developer.

References

• Exploratory Testing in an Agile Context by Elisabeth Hendrickson