Heroku CLI for coding agents

When a coding agent can run shell commands in a project that runs on Heroku, it can use the Heroku CLI to inspect and manage the app from a terminal. The CLI is Heroku’s command-line tool for creating and managing Heroku apps. A coding agent can use it to check release history, inspect configuration, or perform other account actions, depending on the commands and access you allow.

For a low-risk first task, ask the agent to review an app’s release history. The commands below make network requests to Heroku and return JSON, a structured text format that agents can parse. They do not change the app. Install the CLI and authenticate it in the environment where the agent runs, then give the agent a specific app name. The commands follow Heroku’s documented interface; they have not been run for this article.

Install and authenticate

Follow Heroku’s CLI installation instructions for the operating system that runs your agent. The CLI needs Git. On macOS, Heroku documents a Homebrew install. On Linux, the standalone install script puts the CLI in /usr/local/bin/heroku and needs sudo. Then check that the shell can find the CLI:

# macOS with Homebrew
brew install heroku/brew/heroku

# Linux standalone install
curl https://cli-assets.heroku.com/install.sh | sh

heroku --version

Authenticate before starting the agent. Heroku documents heroku login as an interactive sign-in method; it opens a browser so you can authorize the CLI. Complete that step in the agent’s execution environment, or in the same user environment the agent will use. Do not paste an API key or password into the agent prompt. According to Heroku’s authentication documentation, the CLI stores the token in a supported system keychain. If no keychain is available, it falls back to the ~/.netrc file. A HEROKU_API_KEY environment variable overrides both.

A coding agent can run the CLI as a shell command, so it acts with the access available to the authenticated Heroku account. Read-only commands are suitable for inspection tasks. Commands that deploy code, change configuration, or modify add-ons affect Heroku resources, so review those separately before running them.

Inspect an app’s releases

Heroku creates a new release when you deploy code. It also creates one when you change a config var or the app’s add-ons. Release history can help an agent see what changed recently while investigating a production issue. First, list the apps available to the authenticated account:

heroku apps --json

Choose the relevant app from that JSON output. In the next command, replace your-heroku-app with its actual Heroku app name:

APP="your-heroku-app"
heroku releases --app "$APP" --num 20 --json

The first command returns the account’s app list, and the second returns up to 20 release records for the named app. The command reference lists --json for both commands and --num for heroku releases. Both contact Heroku and return JSON. They read this data without changing app settings or deploying code. Many Heroku management commands can return JSON, which an agent can inspect more easily than terminal-formatted tables.

A realistic prompt could be:

Use the Heroku CLI to inspect release history for your-heroku-app. Summarize the recent entries shown in the JSON output. Do not run commands that change the app.

Replace the example app name before assigning the task. The agent should base its summary on the returned records rather than infer a cause for an incident from release history alone.

Keep write commands separate

The CLI also manages configuration variables and add-ons. It manages databases and deployments too. These actions can change live Heroku resources or expose sensitive values. For example, a command that displays configuration variables may reveal credentials, so ask an agent to print them only when the task requires it and handle the output safely.

Do not assume every Heroku command offers a preview or --dry-run mode. Check the command’s documentation before asking the agent to make a change. For deployment or configuration work, have the agent state the exact command and the expected effect before you authorize it.