# Guides

> How to connect LevelFour to your CI, your own tools and your chat, plus configuring the PR bot and the comment box on a recommendation.

Source: https://docs.levelfour.ai/guides


Most of these guides connect LevelFour to something you already run, from a CI pipeline to your own CLI to a chat channel. The PR bot and the comment box on a savings recommendation are the other kind, surfaces LevelFour runs for you.

> **Note**
>
> Most of the code on these pages needs a LevelFour API key before it runs. [Authentication](/authentication) is where keys come from, and [Key scopes](/authentication#key-scopes) is the read versus read-write split. The Slack and Google Chat receivers take the webhook signing secret instead, which [Webhooks](/webhooks) owns.

## The guides

* [Formatting comments](/guides/formatting-comments) is the Markdown the comment box on a savings recommendation understands, and the GitHub syntax it does not
* [Filtering and sorting](/guides/filtering-and-sorting) narrows a cost or recommendation query from the terminal, with the same parameters in the SDKs
* [Virtual tags](/guides/virtual-tags) assigns one tag key to the cost of every connected provider from rules you write, to fix inconsistent tags and split shared costs
* [GitHub Actions](/guides/github-actions) has whole workflow files that comment a cost summary on a pull request and upload a daily report
* [PR bot configuration](/guides/pr-bot-configuration) tunes the bot LevelFour runs on your pull requests, through the optional `.levelfour/config.yml`
* [CI/CD Integration](/guides/ci-cd) gates a pull request on cloud cost with `l4 estimate` and `l4 diff`, in GitHub Actions or GitLab CI
* [Integrate the SDK into your CLI](/guides/integrate-sdk-into-your-cli) embeds the SDK as a library in a CLI your team already ships, for typed objects and language-native errors
* [Integrate l4 into your CLI](/guides/integrate-l4-into-your-cli) shells out to the `l4` binary from scripts, Makefiles and CI runners, with no SDK in the dependency tree
* [Backstage Plugin](/guides/backstage-plugin) builds both halves of a plugin that shows LevelFour cost data in your developer portal
* [Slack Integration](/guides/slack-integration) verifies the signature on a LevelFour webhook and posts the event into a Slack channel
* [Google Chat Integration](/guides/google-chat-integration) does the same for a Google Chat space
* [Scheduled Execution](/guides/scheduled-execution) runs an unattended check on cron or a workflow, and says when webhooks beat a schedule

## Next

* [CLI](/cli) is the `l4` binary several of these call: the command groups, the global flags and the exit codes to script against
* [SDKs](/sdks) is the Python, TypeScript and Go clients the code samples are built on
* [Webhooks](/webhooks) is what LevelFour posts to your endpoint, and the signature the chat receivers verify
* [API reference](/api-reference) is the REST surface underneath all of it