Pi Prompt Authoring

Authors custom system prompt additions for pi coding agent. Pi provides a default system prompt with identity, tools, and guidelines. This skill covers what to add via SYSTEM.md (replace default) or APPEND_SYSTEM.md (extend default).

How Pi's System Prompt Works

Pi builds the system prompt dynamically: identity → tools → guidelines → docs → append → context → skills → metadata.

SYSTEM.md replaces the default. APPEND_SYSTEM.md extends it.

Locations: .pi/SYSTEM.md (project), ~/.pi/agent/SYSTEM.md (global), or --system-prompt (CLI).

See detailed prompt structure for full construction order, tool listing, skills format, and context file loading.

Section 1: Core Principles (Optional)

Define coding standards and architectural preferences. Common categories: simplicity, code quality, codebase health, build verification, security.

See example principles for working examples.