Introducing Atmos LSP: IDE-Native Infrastructure Configuration

March 7, 2026 · 12 min read

We're excited to introduce Atmos LSP, bringing IDE-quality features directly to your infrastructure configuration workflow—no context switching, no manual validation, no documentation hunting.

Atmos LSP provides comprehensive Language Server Protocol integration that transforms how you write and validate Atmos configurations. Get instant feedback on errors, autocomplete for Atmos keywords, hover documentation without leaving your editor, and seamless integration with external language servers for YAML and Terraform validation.

With support for 13+ editors (VS Code, Neovim, Zed, Cursor, Emacs, and more), multiple transport protocols, and deep AI integration—writing infrastructure configuration now feels like writing code in a modern IDE.

The Problem

Infrastructure configuration is error-prone and time-consuming. Engineers constantly:

Context switch between editor and terminal to validate configurations
Run commands manually to check syntax errors (atmos validate stacks)
Search documentation for correct YAML structure and Atmos keywords
Discover errors late during terraform plan or apply
Fix typos manually without autocomplete assistance
Navigate large configs without structural overview

Even simple typos in YAML can cause deployment failures that take hours to debug. The feedback loop is too long, and the cost of mistakes is too high.

The Solution: Atmos LSP

Atmos LSP brings IDE-native infrastructure configuration through the Language Server Protocol (LSP)—the same standard that powers modern code editors.

What You Get:

Real-time validation as you type—catch errors before committing
Autocomplete for Atmos keywords, components, and variables
Hover documentation explains Atmos concepts without leaving your editor
Multi-editor support—works in VS Code, Neovim, Zed, Cursor, Emacs, and 8+ others
External LSP integration—unified YAML and Terraform validation
AI integration—enables AI assistants to validate configurations accurately

Dual-Component Design

Atmos LSP consists of two complementary components:

1. Atmos LSP Server - Native Atmos-specific features

Autocomplete for Atmos keywords (import, components, vars, etc.)
Hover documentation for all Atmos concepts
Real-time Atmos-specific validation
Multi-transport support (stdio, TCP, WebSocket)

2. Atmos LSP Client - External language server integration

Manages multiple LSP servers (yaml-language-server, terraform-ls)
Routes files to appropriate server by type
Aggregates diagnostics from all servers
Provides unified interface for AI tools

Key Features

1. Real-Time Validation

Get instant feedback as you type—no more waiting for atmos validate stacks:

# stacks/prod/vpc.yaml

import:
  - stacks/base  # ❌ Error: imports must be arrays

components:
  terraform:
    vpc:
      vars:
        cidr_block: 10.0.0.0/16      # ✅ Valid
        vpc_ciddr: 10.1.0.0/16       # ⚠️  Warning: Unknown property
                                     #     (did you mean 'cidr_block'?)
        availability_zones:          # ⚠️  Warning: Property deprecated
          - us-east-1a               #     Use 'azs' instead

Validation Triggers:

Real-time as you type
On document save
On document open
Manual validation request

Validation Types:

YAML Syntax - Malformed YAML detection
Atmos Structure - Stack schema validation
Import Arrays - Ensures imports are valid lists
Component Sections - Validates terraform/helmfile structure
Type Safety - Checks value types match expectations

2. Intelligent Autocomplete

Stop memorizing Atmos keywords—let autocomplete guide you:

# Type 'com' and press Ctrl+Space
com|
    ↓
# Autocomplete suggests:
components:
  terraform:
  helmfile:

Autocomplete Categories:

Top-Level Keywords:

import - Import other stack files
components - Define infrastructure components
vars - Stack variables
settings - Stack settings
metadata - Stack metadata

Component Types:

terraform - Terraform components
helmfile - Helmfile components

Common Variables:

namespace, tenant, environment, stage, region
enabled - Enable/disable pattern
tags - Resource tags

Settings:

spacelift - Spacelift integration
atlantis - Atlantis integration
validation - Validation rules

3. Hover Documentation

Get context-aware documentation without leaving your editor:

Hover over import:

**import**

Import other Atmos stack configuration files.

Import paths are relative to the stacks directory.

**Example:**
```yaml
import:
  - catalog/vpc
  - mixins/kubernetes

Note: Imports are processed sequentially, and later imports can override values from earlier imports.

**Documented Keywords:**
- Stack structure: `import`, `components`, `vars`, `settings`, `metadata`
- Component types: `terraform`, `helmfile`
- Stack variables: `namespace`, `tenant`, `environment`, `stage`, `region`
- Common patterns: `enabled` flag, resource `tags`

### 4. Multi-Editor Support (13+ IDEs)

Works with your favorite editor—same experience everywhere:

| Editor | Status | Setup |
|--------|--------|-------|
| **VS Code** | Yes | LSP client extension |
| **Neovim** | Yes | nvim-lspconfig |
| **Cursor** | Yes | LSP client (VS Code fork) |
| **Zed** | Yes | Built-in LSP config |
| **Emacs** | Yes | lsp-mode |
| **Vim** | Yes | vim-lsp plugin |
| **Sublime Text** | Yes | LSP package |
| **Helix** | Yes | languages.toml |
| **IntelliJ IDEA** | Yes | LSP4IJ plugin |
| **Kate** | Yes | LSP client plugin |
| **Lapce** | Yes | Built-in LSP |
| **Atom** | Yes | atom-languageclient |
| **Eclipse** | Yes | LSP4E |

**Universal Setup Pattern:**
```json
{
  "atmos-lsp": {
    "command": "atmos",
    "args": ["lsp", "start"],
    "filetypes": ["yaml"]
  }
}

5. Multi-Transport Support

Choose the right transport for your environment:

stdio (Default) - Desktop IDE integration

atmos lsp start

TCP - Remote development and testing

atmos lsp start --transport tcp --address localhost:7777

WebSocket - Web-based editors

atmos lsp start --transport websocket --address localhost:7777

6. External LSP Server Integration

Atmos LSP Client manages external language servers for unified validation:

Supported Servers:

Server	Purpose	File Types
yaml-language-server	YAML validation with JSON Schema	`.yaml`, `.yml`
terraform-ls	Terraform HCL validation	`.tf`, `.tfvars`, `.hcl`
json-languageserver	JSON validation	`.json`
Any LSP Server	Extensible via config	Custom

Configuration:

# atmos.yaml
lsp:
  enabled: true
  servers:
    yaml-ls:
      command: "yaml-language-server"
      args: ["--stdio"]
      filetypes: ["yaml", "yml"]
      initialization_options:
        yaml:
          validation: true
          hover: true
          completion: true

    terraform-ls:
      command: "terraform-ls"
      args: ["serve"]
      filetypes: ["tf", "tfvars", "hcl"]
      initialization_options:
        experimentalFeatures:
          validateOnSave: true

Benefits:

Single unified validation experience
Automatic file routing by extension
Diagnostic aggregation from multiple servers
Consistent error reporting

7. AI Integration

Enable AI assistants to validate configurations with the validate_file_lsp tool:

You: Validate stacks/prod/vpc.yaml

AI: [Uses validate_file_lsp tool]

    Found 3 issues in stacks/prod/vpc.yaml:

    ERRORS (2):
    1. Line 15, Col 5: Unknown property 'vpc_ciddr'
       Did you mean 'vpc_cidr'?

    2. Line 23, Col 3: Invalid CIDR block format

    WARNINGS (1):
    1. Line 30, Col 7: Property 'availability_zones' is deprecated
       Use 'azs' instead

    Would you like me to help fix these issues?

AI Integration Features:

Precise line and column numbers for errors
Clear error/warning separation
Suggested fixes when available
Summary statistics
Supports all AI providers (Claude, GPT, Gemini, Ollama, etc.)

Learn more: Atmos AI Documentation

Real-World Use Cases

1. Catch Errors Early

Before Atmos LSP:

# Edit stacks/prod/vpc.yaml in editor
vim stacks/prod/vpc.yaml

# Save and exit

# Validate manually in terminal
atmos validate stacks

# ❌ Error: line 15: unknown property 'vpc_ciddr'

# Go back to editor, fix, repeat...
vim stacks/prod/vpc.yaml

With Atmos LSP:

# Edit stacks/prod/vpc.yaml
# Error appears instantly as you type:
vpc_ciddr: 10.0.0.0/16  # ⚠️  Unknown property (did you mean 'vpc_cidr'?)
                        # Red squiggly line appears immediately

# Fix it right away:
vpc_cidr: 10.0.0.0/16   # ✅ Valid - green checkmark

Result: Catch typos in seconds, not minutes.

2. Learn Atmos Structure

Before:

# What top-level keywords are available?
# Open documentation...
# Search for "stack structure"...
# Copy example...

With Atmos LSP:

# Start typing at root level
# Press Ctrl+Space

# Autocomplete shows:
- import
- components
- vars
- settings
- metadata

# Hover over any keyword for documentation

Result: Discover Atmos features without leaving your editor.

3. Unified YAML and Terraform Validation

Before:

# Validate YAML syntax
yamllint stacks/prod/vpc.yaml

# Validate Terraform
cd components/terraform/vpc
terraform validate

# Check Atmos structure
atmos validate stacks

With Atmos LSP:

# All validation happens automatically in editor:
# - YAML syntax (yaml-language-server)
# - Atmos structure (atmos lsp server)
# - Terraform HCL (terraform-ls)

# All errors shown inline with precise locations

Result: One unified validation experience.

4. AI-Powered Configuration Review

Before:

# Copy file contents
# Paste into AI chat
# Ask for validation
# AI provides generic advice

With Atmos LSP + AI:

You: Validate stacks/prod/vpc.yaml

AI: [Uses validate_file_lsp tool for precise validation]

    Found 2 issues:

    1. Line 15, Col 5: 'vpc_ciddr' should be 'vpc_cidr'
    2. Line 30, Col 7: 'availability_zones' is deprecated

    I can fix both issues. Would you like me to:
    1. Update vpc_ciddr → vpc_cidr
    2. Migrate availability_zones → azs array

    Apply fixes? (yes/no)

Result: AI gets precise error locations and can suggest specific fixes.

Getting Started

1. Start LSP Server (IDE Integration)

VS Code Setup:

Create .vscode/settings.json:

{
  "atmos-lsp": {
    "command": "atmos",
    "args": ["lsp", "start"],
    "filetypes": ["yaml"],
    "settings": {
      "atmos": {
        "configPath": "${workspaceFolder}/atmos.yaml"
      }
    }
  }
}

Install a generic LSP client extension (like "LSP" by sublimelsp).

Neovim Setup:

Add to your config:

require('lspconfig').atmos.setup{
  cmd = { 'atmos', 'lsp', 'start' },
  filetypes = { 'yaml' },
  root_dir = function(fname)
    return require('lspconfig.util').root_pattern('atmos.yaml', '.git')(fname)
  end,
}

See Full Setup Guides:

2. Configure External LSP Servers (Optional)

Add to atmos.yaml for YAML and Terraform validation:

lsp:
  enabled: true
  servers:
    # YAML validation
    yaml-ls:
      command: "yaml-language-server"
      args: ["--stdio"]
      filetypes: ["yaml", "yml"]
      root_patterns: ["atmos.yaml", ".git"]
      initialization_options:
        yaml:
          validation: true
          hover: true
          completion: true

    # Terraform validation
    terraform-ls:
      command: "terraform-ls"
      args: ["serve"]
      filetypes: ["tf", "tfvars", "hcl"]
      root_patterns: [".terraform", ".git"]
      initialization_options:
        experimentalFeatures:
          validateOnSave: true

Install External Servers:

# Install yaml-language-server
npm install -g yaml-language-server

# Install terraform-ls
# macOS
brew install terraform-ls

# Linux
curl -LO https://releases.hashicorp.com/terraform-ls/latest/terraform-ls_latest_linux_amd64.zip
unzip terraform-ls_latest_linux_amd64.zip
sudo mv terraform-ls /usr/local/bin/

3. Start Editing

Open any Atmos stack file:

# stacks/prod/vpc.yaml

# Start typing - autocomplete appears
com|
    ↓ (Ctrl+Space)
components:

# Hover for documentation
import:  # ← Hover here for docs
  - catalog/vpc

# Real-time validation
vpc_ciddr: 10.0.0.0/16  # ⚠️  Instant error
vpc_cidr: 10.0.0.0/16   # ✅ Fixed

Advanced Features

Diagnostic Formatting

Three output formats for different use cases:

1. Full Format - Human-readable

ERRORS (2):
1. Line 15, Col 5: Unknown property 'vpc_ciddr' (did you mean 'vpc_cidr'?)
   Source: yaml-language-server

2. Line 23, Col 3: Invalid CIDR block format
   Source: yaml-language-server

WARNINGS (1):
1. Line 30, Col 7: Property 'availability_zones' is deprecated, use 'azs'
   Source: yaml-language-server

2. Compact Format - One line per issue

vpc.yaml:15:5: error: Unknown property 'vpc_ciddr' (yaml-ls)
vpc.yaml:23:3: error: Invalid CIDR block format (yaml-ls)
vpc.yaml:30:7: warning: Property 'availability_zones' is deprecated (yaml-ls)

3. AI-Optimized Format - Structured for AI

Found 3 issue(s) in /stacks/prod/vpc.yaml:

ERRORS (2):
1. Line 15, Col 5: Unknown property 'vpc_ciddr' (did you mean 'vpc_cidr'?)
2. Line 23, Col 3: Invalid CIDR block format

WARNINGS (1):
1. Line 30, Col 7: Property 'availability_zones' is deprecated, use 'azs'

Multi-Server Diagnostic Aggregation

Diagnostics from all LSP servers combined:

# stacks/prod/eks.yaml

import:
  - catalog/vpc       # ✅ Atmos LSP: Valid import

components:
  terraform:
    eks:
      vars:
        cluster_name: "prod"  # ✅ yaml-ls: Valid YAML syntax
        cluster_versio: "1.27"  # ⚠️  yaml-ls: Unknown property
                                # ⚠️  Atmos LSP: Typo detection

Aggregation Features:

Collect from all servers
Deduplicate overlapping diagnostics
Sort by severity and location
Filter by severity level
Per-file diagnostic access

Document Lifecycle

LSP tracks your editing workflow:

1. Document Open → Initial validation + publish diagnostics 2. Document Change → Real-time re-validation (debounced) 3. Document Save → Final validation 4. Document Close → Clear diagnostics, free resources

Thread-Safe:

Document collection protected with RWMutex
Concurrent access supported
No race conditions

Performance

Validation Speed:

Initial validation: <100ms for typical stack files
Real-time updates: <50ms (debounced)
Large files (>1000 lines): <200ms

Resource Usage:

Memory: ~10-50MB per server
CPU: Minimal (validation only on change)
Network: None (all local)

Optimizations:

Debounced validation (avoid validation on every keystroke)
Async diagnostic publishing (non-blocking)
Thread-safe concurrent access

What's Coming Next

Short-term (Next 3 Months)

Go-to-Definition:

import:
  - catalog/vpc  # Ctrl+Click → Opens stacks/catalog/vpc.yaml

components:
  terraform:
    vpc:
      component: vpc-module  # Ctrl+Click → Opens components/terraform/vpc-module/

Document Symbols (Outline View):

Outline:
├── imports (3)
│   ├── catalog/vpc
│   ├── catalog/eks
│   └── mixins/common
├── components
│   ├── terraform
│   │   ├── vpc
│   │   ├── eks
│   │   └── rds
└── vars
    ├── namespace
    ├── environment
    └── region

Medium-term (3-6 Months)

Find References:

vars:
  vpc_id: vpc-123  # Find all references → Shows all files using vpc_id

Rename Symbol:

vars:
  old_name: value  # Rename to new_name → Updates all usages across files

Code Actions (Quick Fixes):

vpc_ciddr: 10.0.0.0/16  # Quick fix: Change to 'vpc_cidr'

Long-term (6+ Months)

Cross-File Validation:

Validate component references exist
Check variable consistency across stacks
Detect circular imports
Dependency analysis

Enhanced Schema Support:

JSON Schema integration
Custom validation rules
Pluggable validators
User-defined schemas

Performance Improvements:

Parsed document caching
Incremental text sync
Background processing
Metrics and profiling

Security & Privacy

LSP Server:

Read-only access to opened documents
No file system access beyond provided documents
No network access
Validates user input safely

LSP Client:

Spawns only configured, trusted servers
Local stdio communication only
No network communication
No credential handling

Privacy:

All processing 100% local
No telemetry or analytics
No document content sent to cloud
External servers may have own policies (check yaml-ls, terraform-ls docs)

Troubleshooting

LSP Server Not Starting

Check:

# Verify atmos is in PATH
which atmos

# Test LSP server manually
atmos lsp start
# Should wait for stdin (Ctrl+C to exit)

# Check Atmos version (LSP requires v1.50.0+)
atmos version

No Autocomplete or Validation

VS Code:

Check Output panel → "Atmos LSP" for errors
Verify LSP client extension is installed
Reload window (Cmd/Ctrl+Shift+P → "Reload Window")

Neovim:

-- Check LSP status
:LspInfo

-- Check logs
:lua vim.cmd('e ' .. vim.lsp.get_log_path())

External LSP Server Not Working

Check server is installed:

# YAML server
yaml-language-server --version

# Terraform server
terraform-ls version

Check configuration:

# atmos.yaml - verify paths are correct
lsp:
  servers:
    yaml-ls:
      command: "yaml-language-server"  # Must be in PATH
      args: ["--stdio"]

Enable debug logging:

# Set environment variable before starting editor
export ATMOS_LOGS_LEVEL=Debug

Learn More

Documentation:

LSP Server Guide - Complete server setup for 13+ editors
LSP Client Guide - External server integration
AI Integration - AI validation tool
Configuration Reference - Full atmos.yaml options

LSP Resources:

Related Features:

Atmos AI - AI-powered infrastructure assistance
Atmos Validation - Validation commands
Atmos Stacks - Stack structure and inheritance

Get Involved:

Happy configuring!

The Problem​

The Solution: Atmos LSP​

Dual-Component Design​

Key Features​

1. Real-Time Validation​

2. Intelligent Autocomplete​

3. Hover Documentation​

5. Multi-Transport Support​

6. External LSP Server Integration​

7. AI Integration​

Real-World Use Cases​

1. Catch Errors Early​

2. Learn Atmos Structure​

3. Unified YAML and Terraform Validation​

4. AI-Powered Configuration Review​

Getting Started​

1. Start LSP Server (IDE Integration)​

2. Configure External LSP Servers (Optional)​

3. Start Editing​

Advanced Features​

Diagnostic Formatting​

Multi-Server Diagnostic Aggregation​

Document Lifecycle​

Performance​

What's Coming Next​

Short-term (Next 3 Months)​

Medium-term (3-6 Months)​

Long-term (6+ Months)​

Security & Privacy​

Troubleshooting​

LSP Server Not Starting​

No Autocomplete or Validation​

External LSP Server Not Working​

Learn More​

The Problem

The Solution: Atmos LSP

Dual-Component Design

Key Features

1. Real-Time Validation

2. Intelligent Autocomplete

3. Hover Documentation

5. Multi-Transport Support

6. External LSP Server Integration

7. AI Integration

Real-World Use Cases

1. Catch Errors Early

2. Learn Atmos Structure

3. Unified YAML and Terraform Validation

4. AI-Powered Configuration Review

Getting Started

1. Start LSP Server (IDE Integration)

2. Configure External LSP Servers (Optional)

3. Start Editing

Advanced Features

Diagnostic Formatting

Multi-Server Diagnostic Aggregation

Document Lifecycle

Performance

What's Coming Next

Short-term (Next 3 Months)

Medium-term (3-6 Months)

Long-term (6+ Months)

Security & Privacy

Troubleshooting

LSP Server Not Starting

No Autocomplete or Validation

External LSP Server Not Working

Learn More