OpenCode Configuration Skill

Understand and manage OpenCode configuration files in JSON or Markdown format, with proper precedence between global and project settings. This skill emphasizes research-driven verification because configuration details change over time.

When to use me

• Setting up OpenCode for a new project with custom settings
• Creating team-wide configuration standards
• Understanding why certain settings aren't being applied (precedence issues)
• Migrating from deprecated configuration patterns to current best practices
• Verifying configuration details against official documentation

What I do

• Explain OpenCode configuration formats (JSON/JSONC vs Markdown with YAML frontmatter)
• Clarify precedence order between global, project, and environment-based configs
• Provide examples for common configuration scenarios (models, permissions, tools, modes)
• Validate configuration files and check for common issues using included scripts
• Emphasize research-driven verification using search tools to stay current with changes
• Generate configuration files with proper schema references and variable substitution
• Include validation script (scripts/validate-config.sh) to check existing configuration files

Examples

# Create a project-specific opencode.json with custom model
cat > opencode.json << EOF
{
  "$schema": "https://opencode.ai/config.json",
  "model": "anthropic/claude-haiku-4-5",
  "permission": {
    "edit": "ask",
    "bash": "ask"
  }
}
EOF

# Create a global mode using Markdown
mkdir -p ~/.config/opencode/modes/
cat > ~/.config/opencode/modes/review.md << 'EOF'
---
temperature: 0.1
tools:
  write: false
  edit: false
  bash: false
---

You are in code review mode. Focus on code quality, potential bugs, and security considerations without making direct changes.
EOF

Output format

When analyzing configuration:

config_source: ~/.config/opencode/opencode.json
config_type: global
format: json
precedence: 2/6
effective_settings:
  model: anthropic/claude-sonnet-4-5
  autoupdate: true

When creating configuration:

{
  "status": "created",
  "file": ".opencode/modes/debug.md",
  "format": "markdown",
  "precedence": "project"
}

Notes

• Critical: OpenCode configuration changes frequently. ALWAYS verify details using search tools (searxngsearxngwebsearch, searxngweburlread) before providing specific implementation guidance.
• Configuration precedence (later overrides earlier):

1. Remote config (.well-known/opencode) 2. Global config (~/.config/opencode/opencode.json) 3. Custom config (OPENCODECONFIG env var) 4. Project config (opencode.json in project) 5. .opencode directories (agents, commands, plugins) 6. Inline config (OPENCODECONFIG_CONTENT env var)

• JSON and JSONC formats are supported for opencode.json; Markdown with YAML frontmatter is supported for modes, agents, commands, etc.
• The $schema field provides validation and autocomplete in editors.
• Use {env:VAR} and {file:path} for variable substitution in config files.
• Modes are now configured through the agent option (deprecated mode option).