Understanding robots.txt for PHP Websites

After creating an XML sitemap for the Jersey News Aggregator and wider Auspice Darer website project, the next step was understanding another file that search engines pay close attention to: robots.txt.

While a sitemap helps search engines discover content, robots.txt helps control what they should and should not crawl.

Both files work together, and both play an important role in how a website is indexed.

What Is robots.txt?

A robots.txt file is a simple text file placed in the root directory of a website.

For example:

https://www.example.com/robots.txt

When a search engine visits a website, one of the first files it requests is robots.txt.

The file contains instructions that tell search engine crawlers which parts of the site are available for crawling and which areas should be ignored.

A basic robots.txt file might look like this:

User-agent: *

Allow: /

Disallow: /admin/

Sitemap: https://www.example.com/sitemap.xml

In plain English this means:

• All search engines are allowed to crawl the website.

• The admin directory should not be crawled.

• The sitemap can be found at the specified location.

Why robots.txt Matters

When I first began developing the project, the focus was on functionality rather than search engine behaviour.

As the site expanded, however, it became clear that not every directory was intended for public discovery.

The website contains:

• Public pages

• Search pages

• News archives

• API endpoints

• Data storage directories

• Internal processing scripts

Search engines should see the public content.

They do not need to crawl internal infrastructure.

Without guidance, crawlers may waste resources exploring areas that provide little value to visitors.

Areas That Should Not Be Crawled

For many PHP projects, common candidates include:

/admin/
/api/
/cache/
/data/
/includes/

These directories often contain:

• Administrative tools

• Backend scripts

• Cached content

• Database files

• Shared code libraries

None of these are useful search results.

Preventing unnecessary crawling helps search engines focus on content that visitors actually want to find.

A Practical Example

For the Auspice Darer project, the robots.txt file eventually evolved into something similar to:

User-agent: *

Allow: /

Disallow: /auspicedarer/api/
Disallow: /auspicedarer/cache/
Disallow: /auspicedarer/data/

Sitemap: https://www.dariuspearce.com/sitemap.xml

This allows search engines to access all public pages while avoiding backend infrastructure.

The sitemap location is also provided directly within the file.

This creates a simple roadmap for search engines to follow.

Common Misunderstandings

One of the most common misconceptions is that robots.txt provides security.

It does not.

The file is publicly accessible.

Anyone can view it by visiting:

https://www.example.com/robots.txt

For this reason, robots.txt should never be used to protect sensitive information.

If a directory genuinely requires protection, proper authentication and access controls should be used instead.

robots.txt merely provides instructions to compliant search engines.

robots.txt and Search Console

Google Search Console provides useful tools for checking whether search engines can access important pages.

After updating a robots.txt file, it is worth verifying that:

• Important pages remain crawlable.

• The sitemap is accessible.

• No critical content has been blocked accidentally.

A single misplaced rule can sometimes prevent large portions of a website from being indexed.

Less Is Often More

One lesson I learned while working on the project was that robots.txt files are often simpler than developers expect.

There can be a temptation to create dozens of rules and exceptions.

In practice, a small number of well-considered directives is usually sufficient.

The goal is not to control every possible crawler action.

The goal is simply to guide search engines towards useful content and away from unnecessary infrastructure.

Final Thoughts

XML sitemaps and robots.txt work together.

The sitemap tells search engines what content exists.

robots.txt tells them where they should focus their attention.

Neither file is complicated, but both can have a significant impact on how efficiently a website is crawled and indexed.

For any PHP website, whether it consists of a handful of pages or a large content platform, taking the time to configure robots.txt properly is a small investment that can provide long-term benefits for search visibility and site management.