pi-swift

Swift reimplementation of the TypeScript-based pi-mono project, built with a strict parity-first migration strategy.

Project Goal

This repository aims to recreate the core functionality of pi-mono in Swift while preserving behavior and avoiding regressions.

Key goals:

• Feature parity with ../pi-mono
• Regression-safe migration through tests
• Incremental delivery by phases
• Documentation-driven implementation (PRD, architecture, plan)

Migration Principles

• Behavior parity over line-by-line translation
• Test-first implementation for each task
• Update task status only after tests + build + docs are complete
• Keep module docs in sync with code changes
• Use atomic commits (one coherent change per commit)

Current Workflow

1. Pick one unfinished task from docs/PLAN.md
2. Read the corresponding pi-mono source/tests
3. Write tests (or parity fixtures) first
4. Implement in Swift
5. Run tests and compile checks
6. Update docs
7. Only then mark the task as done

Documentation

• PRD: docs/PRD.md
• Architecture: docs/ARCHITECTURE.md
• Execution Plan: docs/PLAN.md
• Project rules: AGENTS.md

Scope (Initial Priority)

The migration is planned in dependency order:

1. pi-ai
2. pi-agent-core
3. pi-tui
4. pi-coding-agent
5. Peripheral modules (mom, pods, web-ui)

Status

Project bootstrapping/planning docs are in place, and P1 groundwork is underway:

• P1-1 SwiftPM/module skeleton: implemented and verified
• P1-2 shared test infrastructure (fixtures/goldens): implemented and verified
• P1-3 cross-module foundational core types: implemented and verified

P2 has started:

• P2-1 pi-ai foundational model registry: implemented and verified
• P2-2 pi-ai unified context/message/event types: implemented and verified
• P2-3 pi-ai utility foundations (SSE parsing, JSON parsing, validation, overflow detection): implemented and verified
• P2-4 first provider adapter (OpenAI Responses, mock-driven event processor): implemented and verified
• P2-5 Anthropic adapter (mock-driven thinking/text/tool mapping + OAuth tool-name normalization regression tests): implemented and verified
• P2-6 Google/Vertex family adapter core (mock-driven Google stream mapping + thinking signature / empty-stream / missing-args regression tests): implemented and verified
• P2-7 OAuth and provider credential helpers (registry, expiry-aware refresh, API key injection): implemented and verified
• P2-8 pi-ai regression/coverage push: implemented and verified (docs/reports/pi-ai-coverage.md)

P3 has started:

• P3-1 pi-agent-core state/message/event foundational types: implemented and verified
• P3-2 pi-agent-core single-turn agent loop (streamed assistant event -> agent event sequence): implemented and verified
• P3-3 pi-agent-core multi-turn tool execution loop (tool-call execution, tool-result injection, next-turn replay): implemented and verified
• P3-4 pi-agent-core runtime controls (continue/retry entrypoint, steering/follow-up loops, abort controller, request-options plumbing): implemented and verified
• P3-5 pi-agent-core regression test completion + coverage report: implemented and verified (/Users/anyuan/Development/pi-swift/docs/reports/pi-agent-core-coverage.md)

Next step: P6-2 (pi-mom Slack bot migration) in /Users/anyuan/Development/pi-swift/docs/PLAN.md.