Natural languages
IntelliJ IDEA helps ensure your codebase is error-free and consistent not only in terms of correct programming languages syntax, but also in terms of proper grammar, spelling, and style. In addition to common text files like your project's README.md, it checks natural language consistency and correctness in your source files, including names of identifiers and variables, contents of string literals, comments, Javadocs, and even your commit messages.
IntelliJ IDEA can also analyze agent instruction files, such as AGENTS.md or SKILL.md for conflicting instructions, unclear wording, and missing information.
Enable the Natural Languages plugin
This functionality relies on the Natural Languages plugin, which is bundled and enabled in IntelliJ IDEA by default. If the relevant features are not available, make sure that you did not disable the plugin.
Press Ctrl+Alt+S to open settings and then select .
Find the Natural Languages plugin and click Enable.
By default, IntelliJ IDEA includes support for the English language. If you open a file with several paragraphs of text in another supported language, IntelliJ IDEA will detect it and offer a suggestion to download and enable checks for that language. You can see the list of supported languages and enable them in the settings.
Add spelling and grammar checks for a language
Press Ctrl+Alt+S to open settings and then select .
Click
in the list of languages and select your language.
IntelliJ IDEA will download the language model and enable spelling and grammar checks for it.
To learn how to keep language bundles up to date, refer to Download language updates automatically.
Analyze AI agent specification files
IntelliJ IDEA helps you improve specifications for AI agents by detecting potential security issues, conflicting or ambiguous instructions, and gaps in semantic coverage. When enabled, these inspections run automatically when you open AGENTS.md, SKILL.md, or other Markdown specification files.
This feature may consume AI credits and is disabled by default.
Enable AI agents specifications analysis
Press Ctrl+Alt+S to open settings and then select .
Select the Enable AI agent specification analysis checkbox.