Atmos Config

DevOps & Security

atmos-config

Atmos Config is an Agent Skill for devops & security published in the cloudposse/atmos repository on GitHub: a SKILL.md instruction file an AI agent can load to do this task.

Atmos root configuration: atmos.yaml discovery, precedence, deep merging, base_path, imports, minimal bootstrap, and routing to narrower Atmos skills

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How to use this skill

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Review files and risks before approving any action.

Prompt to paste

Inspect the Agent Skill at https://github.com/cloudposse/atmos/blob/HEAD/agent-skills/skills/atmos-config/SKILL.md and all supporting files. Report provenance, permissions, scripts, dependencies, and security risks. Propose an exact installation into .agents/skills/atmos-config, but wait for my approval before writing files or running scripts.

Copying this prompt does not install or run the skill. Review third-party files before use.

Atmos Root Configuration

Use this skill for the root mechanics of atmos.yaml: how Atmos finds config files, merges them, resolves project-relative paths, imports modular config, and routes section-specific work to the right skill. Do not use this skill as a catchall for every atmos.yaml section.

Configuration Discovery

Atmos searches for atmos.yaml in this order:

--config CLI flag or ATMOS_CLI_CONFIG_PATH.
Active profile selected by --profile or ATMOS_PROFILE.
Current working directory.
Git repository root.
Parent directory walk.
Home directory.
System directory.

When multiple configuration files apply, Atmos deep-merges them. More specific sources override broader defaults.

Root Layout

Use base_path for the project root that relative paths resolve from. Keep the root config small and point subsystem paths at their owning directories:

base_path: ""

stacks:
  base_path: stacks
  included_paths:
    - "**/*"
  excluded_paths:
    - "**/_defaults.yaml"
    - "catalog/**/*"
  name_template: "{{ .vars.stage }}"

components:
  terraform:
    base_path: components/terraform

workflows:
  base_path: stacks/workflows

For deeper path/layout guidance, load atmos-project-layout.

Modular Imports

Use import to split root config into focused files:

import:
  - atmos.d/stacks.yaml
  - atmos.d/components.yaml
  - atmos.d/auth.yaml
  - atmos.d/toolchain.yaml

Imported files are deep-merged into the active configuration. Keep imported files aligned with the subsystem they configure and load the subsystem skill before changing that section.

Routing

Need	Load
Root discovery, merge order, imports, minimal bootstrap	stay in `atmos-config`
Project paths, `base_path`, path conventions, relative path resolution	`atmos-project-layout`
Profiles, `--profile`, `ATMOS_PROFILE`, profile directory merge behavior	`atmos-profiles`
Global CLI behavior, `settings`, `logs`, `errors`, `env`, `docs`, `metadata`	`atmos-settings`
Stack manifests, inheritance, stack imports, vars, locals, stack naming	`atmos-stacks`
Component structure, abstract components, metadata, component inheritance	`atmos-components`
Terraform/OpenTofu commands, backend defaults, Terraform component settings	`atmos-terraform`
Helmfile, Packer, or Ansible component behavior	`atmos-helmfile`, `atmos-packer`, `atmos-ansible`
Workflows section and workflow syntax	`atmos-workflows`
Custom commands and aliases	`atmos-custom-commands`
Auth providers, identities, keyring, cloud auth conventions	`atmos-auth`
Stores and store-backed YAML functions	`atmos-stores`
Tool versions, `dependencies.tools`, registries, shell/PATH integration	`atmos-toolchain`
Native CI, GitHub Actions, Atlantis, matrices, CI outputs	`atmos-ci`
Schemas and validation policy configuration	`atmos-schemas`, `atmos-validation`
Templates and YAML functions	`atmos-templates`, `atmos-yaml-functions`
Vendoring external components	`atmos-vendoring`
Introspection commands and querying resolved config	`atmos-introspection`

For a compact map of top-level sections, read references/sections-reference.md.

Guardrails

Keep atmos-config examples minimal; detailed subsystem examples belong in their narrower skills.
Before editing a subsystem section, load the owning skill from the routing table.
Prefer atmos describe config or atmos describe component when verifying merge or path behavior.