Docker Compose Skill

Overview

This skill provides comprehensive Docker Compose management, enabling AI agents to orchestrate multi-container applications, manage services, inspect logs, and troubleshoot containerized environments with progressive disclosure for optimal context usage.

Context Savings: ~92% reduction

• MCP Mode: ~25,000 tokens always loaded (multiple tools + schemas)
• Skill Mode: ~700 tokens metadata + on-demand loading

When to Use

• Managing local development environments
• Orchestrating multi-container applications
• Debugging service connectivity and networking
• Monitoring container logs and health
• Building and updating service images
• Testing containerized application stacks
• Troubleshooting service failures
• Managing application lifecycle (start, stop, restart)

Requirements

• Docker Engine installed and running
• Docker Compose V2 (docker compose) or V1 (docker-compose)
• Valid docker-compose.yml file in project
• Appropriate permissions for Docker socket access

Quick Reference

# List running services
docker compose ps

# View service logs
docker compose logs <service>

# Start services
docker compose up -d

# Stop services
docker compose down

# Rebuild services
docker compose build

# Execute command in container
docker compose exec <service> <command>

Tools

The skill provides 15 tools across service management, monitoring, build operations, and troubleshooting categories:

Service Management (5 tools)

up

Start services defined in docker-compose.yml.

Parameter	Type	Description	Default
detached	boolean	Run in detached mode	true
build	boolean	Build images before starting	false
force_recreate	boolean	Recreate containers	false
project_name	string	Project name override	directory name
services	array	Specific services to start	all services

Example:

docker compose up -d
docker compose up --build
docker compose up web api

Safety: Requires confirmation for production environments.

down

Stop and remove containers, networks, volumes.

Parameter	Type	Description	Default
volumes	boolean	Remove volumes (BLOCKED)	false
remove_orphans	boolean	Remove orphaned containers	false
project_name	string	Project name override	directory name

Example:

docker compose down
docker compose down --remove-orphans

Safety: Volume removal (-v flag) is BLOCKED by default. Requires confirmation.

start

Start existing containers without recreating them.

Parameter	Type	Description	Default
services	array	Specific services to start	all services
project_name	string	Project name override	directory name

Example:

docker compose start
docker compose start web

stop

Stop running containers without removing them.

Parameter	Type	Description	Default
timeout	number	Shutdown timeout (seconds)	10
services	array	Specific services to stop	all services
project_name	string	Project name override	directory name

Example:

docker compose stop
docker compose stop --timeout 30 web

restart

Restart services (stop + start).

Parameter	Type	Description	Default
timeout	number	Shutdown timeout (seconds)	10
services	array	Specific services to restart	all services
project_name	string	Project name override	directory name

Example:

docker compose restart
docker compose restart api

Status & Logs (3 tools)

ps

List containers with status information.

Parameter	Type	Description	Default
all	boolean	Show all containers (including stopped)	false
services	array	Filter by services	all services
project_name	string	Project name override	directory name

Example:

docker compose ps
docker compose ps --all

Output Fields: NAME, IMAGE, STATUS, PORTS

logs

View service logs with streaming support.

Parameter	Type	Description	Default
services	array	Services to view logs for	all services
follow	boolean	Follow log output (stream)	false
tail	number	Number of lines to show	100
timestamps	boolean	Show timestamps	false
since	string	Show logs since timestamp/duration	none
project_name	string	Project name override	directory name

Example:

docker compose logs web
docker compose logs --tail 50 --follow api
docker compose logs --since "2024-01-01T10:00:00"

Note: Follow mode automatically terminates after 60 seconds to prevent indefinite streaming.

top

Display running processes in containers.

Parameter	Type	Description	Default
services	array	Services to inspect	all services
project_name	string	Project name override	directory name

Example:

docker compose top
docker compose top web

Output: Process list with PID, USER, TIME, COMMAND

Build & Images (3 tools)

build

Build or rebuild service images.

Parameter	Type	Description	Default
no_cache	boolean	Build without cache	false
pull	boolean	Pull newer image versions	false
parallel	boolean	Build in parallel	true
services	array	Services to build	all services
project_name	string	Project name override	directory name

Example:

docker compose build
docker compose build --no-cache web
docker compose build --pull

Safety: Requires confirmation for no-cache builds (resource-intensive).

pull

Pull service images from registry.

Parameter	Type	Description	Default
ignore_pull_failures	boolean	Continue if pull fails	false
services	array	Services to pull	all services
project_name	string	Project name override	directory name

Example:

docker compose pull
docker compose pull web api

Safety: Requires confirmation for production environments.

images

List images used by services.

Parameter	Type	Description	Default
project_name	string	Project name override	directory name

Example:

docker compose images

Output Fields: CONTAINER, REPOSITORY, TAG, IMAGE ID, SIZE

Execution (2 tools)

exec

Execute a command in a running container.

Parameter	Type	Description	Required
service	string	Service name	Yes
command	array	Command to execute	Yes
user	string	User to execute as	container default
workdir	string	Working directory	container default
env	object	Environment variables	none
project_name	string	Project name override	directory name

Example:

docker compose exec web bash
docker compose exec -u root api ls -la /app
docker compose exec db psql -U postgres

Safety:

• Destructive commands (rm -rf, dd, mkfs) are BLOCKED
• Root user execution requires confirmation
• Default timeout: 30 seconds

run

Run a one-off command in a new container.

Parameter	Type	Description	Default
service	string	Service to run	Required
command	array	Command to execute	service default
rm	boolean	Remove container after run	true
no_deps	boolean	Don't start linked services	false
user	string	User to execute as	container default
env	object	Environment variables	none
project_name	string	Project name override	directory name

Example:

docker compose run --rm web npm test
docker compose run --no-deps api python manage.py migrate

Safety: Requires confirmation for commands that modify data.

Configuration (2 tools)

config

Validate and view the Compose file configuration.

Parameter	Type	Description	Default
resolve_image_digests	boolean	Pin image tags to digests	false
no_interpolate	boolean	Don't interpolate env vars	false
project_name	string	Project name override	directory name

Example:

docker compose config
docker compose config --resolve-image-digests

Output: Parsed and merged Compose configuration

port

Print the public port binding for a service port.

Parameter	Type	Description	Required
service	string	Service name	Yes
private_port	number	Container port	Yes
protocol	string	Protocol (tcp/udp)	tcp
project_name	string	Project name override	directory name

Example:

docker compose port web 80
docker compose port db 5432

Output: <host>:<port> binding

Common Workflows

Start a Development Environment

# 1. Validate configuration
docker compose config

# 2. Pull latest images
docker compose pull

# 3. Build custom images
docker compose build

# 4. Start services in detached mode
docker compose up -d

# 5. Check service status
docker compose ps

# 6. View logs
docker compose logs --tail 100

Troubleshoot a Failing Service

# 1. Check container status
docker compose ps --all

# 2. View service logs
docker compose logs --tail 200 failing-service

# 3. Inspect running processes
docker compose top failing-service

# 4. Check configuration
docker compose config

# 5. Restart the service
docker compose restart failing-service

# 6. If needed, recreate container
docker compose up -d --force-recreate failing-service

Update Service Images

# 1. Pull latest images
docker compose pull

# 2. Stop services
docker compose down

# 3. Rebuild if using custom Dockerfiles
docker compose build --pull

# 4. Start with new images
docker compose up -d

# 5. Verify services
docker compose ps

Debug Service Connectivity

# 1. Check running services
docker compose ps

# 2. Inspect port mappings
docker compose port web 80
docker compose port api 3000

# 3. Exec into container
docker compose exec web sh

# 4. Test connectivity (from inside container)
docker compose exec web curl api:3000/health

# 5. Check logs for errors
docker compose logs web api

Clean Up Environment

# 1. Stop all services
docker compose down

# 2. Remove orphaned containers
docker compose down --remove-orphans

# 3. View images
docker compose images

# 4. Clean up (manual - volume removal BLOCKED)
# Volumes require manual cleanup with explicit confirmation

Configuration

Environment Variables

Variable	Description	Default
COMPOSE_PROJECT_NAME	Default project name	directory name
COMPOSE_FILE	Compose file path	docker-compose.yml
COMPOSE_PATH_SEPARATOR	Path separator for multiple files	: (Linux/Mac), ; (Windows)
DOCKER_HOST	Docker daemon socket	unix:///var/run/docker.sock
COMPOSE_HTTP_TIMEOUT	HTTP timeout for API calls	60
COMPOSE_PARALLEL_LIMIT	Max parallel operations	unlimited

Setup

1. Install Docker Engine:

   # macOS
   brew install --cask docker
   
   # Linux (Ubuntu/Debian)
   sudo apt-get update
   sudo apt-get install docker-ce docker-ce-cli containerd.io docker-compose-plugin
   
   # Windows
   # Download Docker Desktop from docker.com
   

2. Verify Docker Compose:

   # Check Docker version
   docker --version
   
   # Check Compose version
   docker compose version
   

3. Create docker-compose.yml:

   version: '3.8'
   services:
     web:
       build: .
       ports:
         - '8080:80'
     db:
       image: postgres:14
       environment:
         POSTGRES_PASSWORD: example
   

4. Test the skill:

   docker compose config
   docker compose ps
   

Safety Features

Blocked Operations

The following operations are BLOCKED by default to prevent accidental data loss:

• Volume removal: docker compose down -v (BLOCKED - requires manual confirmation)
• Full cleanup: docker compose down -v --rmi all (BLOCKED - extremely destructive)
• Destructive exec: rm -rf, dd, mkfs, sudo rm inside containers (BLOCKED)
• Force removal: docker compose rm -f (BLOCKED - use stop then rm)

Confirmation Required

These operations require explicit confirmation:

• Building with --no-cache (resource-intensive)
• Pulling images in production environments
• Starting services with --force-recreate
• Executing commands as root user
• Running commands that modify databases
• Stopping services with very short timeouts

Auto-Terminating Operations

The following operations auto-terminate to prevent resource issues:

• Log following (--follow): 60-second timeout
• Service execution (exec): 30-second timeout
• One-off commands (run): 60-second timeout

Error Handling

Common Errors:

Error	Cause	Fix
docker: command not found	Docker not installed	Install Docker Engine
Cannot connect to Docker daemon	Docker not running	Start Docker service
network ... not found	Network cleanup issue	Run docker compose down then up
port is already allocated	Port conflict	Change port mapping or stop conflicting service
no configuration file provided	Missing compose file	Create docker-compose.yml
service ... must be built	Image not built	Run docker compose build

Recovery:

• Validate configuration: docker compose config
• Check Docker status: docker info
• View service logs: docker compose logs
• Force recreate: docker compose up -d --force-recreate
• Clean restart: docker compose down && docker compose up -d

Integration with Agents

This skill integrates with the following agents:

Primary Agents

• devops: Local development, CI/CD integration, container orchestration
• developer: Application development, testing, debugging

Secondary Agents

• qa: Integration testing, test environment setup
• incident-responder: Debugging production issues, service recovery
• cloud-integrator: Cloud deployment, migration to Kubernetes
• performance-engineer: Performance testing, resource optimization

Progressive Disclosure

The skill uses progressive disclosure to minimize context usage:

1. Initial Load: Only metadata and tool names (~700 tokens)
2. Tool Invocation: Specific tool schema loaded on-demand (~100-150 tokens)
3. Result Streaming: Large outputs (logs) streamed incrementally
4. Context Cleanup: Old results cleared after use

Context Optimization:

• Use --tail to limit log output
• Use service filters to target specific containers
• Prefer ps over ps --all for active services only
• Use --since for time-bounded log queries

Troubleshooting

Skill Issues

Docker Compose not found:

# Check Docker Compose version
docker compose version

# If using V1, try:
docker-compose version

# Update to V2 (recommended)
# Docker Compose V2 is integrated into Docker CLI

Permission denied:

# Add user to docker group (Linux)
sudo usermod -aG docker $USER
newgrp docker

# Verify permissions
docker ps

Compose file issues:

# Validate syntax
docker compose config

# Check for errors
docker compose config -q

# View resolved configuration
docker compose config --resolve-image-digests

Network issues:

# List networks
docker network ls

# Remove unused networks
docker network prune

# Recreate services
docker compose down
docker compose up -d

Performance Considerations

• Build caching: Use layer caching for faster builds; avoid --no-cache unless necessary
• Parallel operations: Docker Compose V2 parallelizes by default; use COMPOSE_PARALLEL_LIMIT to control
• Resource limits: Define CPU/memory limits in compose file to prevent resource exhaustion
• Log rotation: Use logging drivers to prevent disk space issues
• Volume cleanup: Regularly clean unused volumes (requires manual confirmation)

Related

• Docker Compose Documentation: https://docs.docker.com/compose/
• Compose File Reference: https://docs.docker.com/compose/compose-file/
• Docker CLI: https://docs.docker.com/engine/reference/commandline/cli/
• Kubernetes Migration: .claude/skills/kubernetes-flux/ (Kubernetes orchestration)
• Cloud Run: .claude/skills/cloud-run/ (GCP Cloud Run deployment)

Sources

• Docker Compose Documentation
• Docker Compose V2
• Compose Specification
• Docker Best Practices