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 at runtime. The construction follows this order:

Default System Prompt Structure

When using the default prompt, pi constructs it with these sections:

1. Identity statement - "You are an expert coding assistant operating inside pi, a coding agent harness. You help users by reading files, executing commands, editing code, and writing new files."
2. Available tools - List of enabled tools with one-line descriptions
3. Guidelines - Context-aware guidelines based on which tools are available
4. Pi documentation references - Paths to README, docs, and examples
5. Append system prompt - Content from APPEND_SYSTEM.md or --append-system-prompt
6. Project context - Loaded AGENTS.md/CLAUDE.md files
7. Skills section - XML-formatted list of available skills (only if read tool is enabled)