01. MVP Milestones

Version slices

M0 — Spec Freeze

• [x] Product positioning
• [x] Electron route
• [x] Rust host core route
• [x] English-first globalization route
• [x] Plugin system architecture
• [x] Private GitHub repository initialized

M1 — App Skeleton

Status: Implemented (MVP)

Goal: bootable desktop shell with dual backend skeletons.

Deliverables:

• pnpm monorepo
• Electron app (main/preload/renderer)
• English locale source pack
• Rust host-core crate skeleton + healthcheck
• Node agent-runtime package skeleton
• IPC healthcheck end-to-end
• reserved PluginManager/CommandPalette interfaces

Exit criteria:

• pnpm dev opens window in English
• Electron can call Rust host healthcheck
• protocol/version handshake visible in logs

M2 — Pi Chat Runtime

Status: Implemented (MVP)

Goal: real streaming chat.

Deliverables:

• pi runtime integration
• provider/model settings
• secret storage
• prompt/abort
• stream event UI
• session persistence baseline

Exit criteria:

• configure key and chat successfully
• streamed tokens visible
• history survives restart

M3 — Workspace Tools

Status: Implemented (MVP)

Goal: controlled local agency.

Deliverables:

• project open
• Read/Glob/Grep/Write/Edit/Bash via Rust host
• permission cards
• tool traces

Exit criteria:

• complete one approved local modification on a real project
• denied permission path is correct

M4 — Plugin Foundation

Status: Implemented (MVP)

Goal: user-installable local extension system.

Deliverables:

• PluginManager
• manifest validation
• local/dev plugin load
• command palette plugin commands
• sample plugin e2e
• permission declaration UI

Exit criteria:

• load example plugin
• run plugin command
• register low-risk agent tool
• disable removes contributions

M5 — Desktop Hardening

Status: Complete except credential-gated macOS notarization

Goal: daily-usable package.

Deliverables:

• packaging (macOS arm64, Windows x64, and Linux x64 tag artifacts; D126)
• settings polish
• logging/error boundaries
• session management basics
• isolation verification

Progress:

• [x] packaging scaffold (electron-builder macOS arm64 --dir, host/sidecar resources)
• [x] substantial settings/session/UI polish on main
• [x] code signing lanes (unsigned local default; Developer ID + hardened runtime + entitlements injected by scripts/release-macos.sh, D078)
• [x] custom app icon (generated pi mark → build/icon.icns, D079)
• [x] isolation/logging hardening (renderer sandbox D081, NDJSON log channels D082, crash supervision D080, window state D083)
• [x] packaged macOS update discovery, fixed release link, typed update state, and tag-workflow feed assets (manual delivery, D120 / ADR 0022)
• [ ] full DMG + notarization — runbook ready (06-release-runbook); blocked only on Apple Developer credentials (operational, not code)

M6 — Plan Operating State

Status: Complete (2026-08-05)

Goal: replace the former Chat operating profile with host-authoritative Plan and Goal contract states on the same pi Agent, including a separate approval boundary.

Deliverables:

• Agent | Plan | Goal selector with Agent as the default
• persisted session/settings/scheduled chat → plan migration
• protocol v9 and schema v11 with immutable host-written .pi/plan/*.md and .pi/goal/*.md artifacts, structured title/question fields, and plan_approvals artifact/execution fields
• Rust-owned mode resolution, Plan tool policy, selectable shell catalog with fallback and turn-pinned identity, streamed Bash output, bounded timeout, and process-tree cancellation
• one-Agent EnterPlanMode / SubmitPlan and EnterGoalMode / SubmitGoal lifecycles with approve/reject-only resolution and fail-closed recovery
• Plan artifact approval IPC/RPC/events, current-lifetime renderer projection, pending-only reload hydration, shell selection, approval UX, and EN/zh-CN copy
• plugin denial, scheduled contract rejection, selectable shell execution, focused unit/integration verification, and the current extension/subagent flows documented in the E2E plan

Exit criteria:

• only one pi Agent is used before, during, and after planning
• Plan denies Write/Edit/plugin tools but exposes Bash under the selected permission mode, including Auto's explicit mutation tradeoff
• approval is separate from generic tool permission, atomically selects the Agent permission mode, and defaults the UI selection to Ask
• reject and expiry leave the session in Plan; a host restart interrupts pending/queued/running work without replay, while an already-approved interrupted execution leaves the session Agent
• renderer retains the latest Plan snapshot only for its current lifetime; plans.pending restores only a still-pending row and deadline after a same-Host reload, while terminal cards are not rehydrated
• each submitted Markdown snapshot is preserved byte-for-byte in a unique .pi/plan/*.md artifact with recorded path/hash/size, and approval opens it
• Host/storage recovery, pending hydration, same-lifetime terminal controls, and rejected/approved terminal-card absence after same-Host renderer reload are evidenced. Local E2E execution remains opt-in outside an explicitly requested acceptance run

Acceptance evidence: host-core migration/policy/recovery tests, test:e2e:plan, test:e2e:plan-ui, desktop/runtime/shared/i18n suites, full JavaScript build/typecheck/lint, and Electron boot/supervision probes. The same-Host UI run covers pending restore, live terminal controls, stable Electron/Host identity, and terminal-card absence after renderer reload; E2E-108/E2E-109 cover Host restart interruption and no replay.

M6+ (Current product increment)

Implemented after the M6 Plan checkpoint:

• Goal contracts and autonomous post-approval execution
• standalone MCP and Skills management with global/project activation scopes
• bounded Subagents with project, user, and builtin definition sources
• plugin marketplace installation/update review and global plugin launcher
• session import, scheduled task records, notifications, clipboard file paste, slash commands, @ file references, and next-turn composer configuration

Remaining work is tracked as product hardening rather than unstarted MVP scope:

• stronger plugin runtime sandboxing and publisher signatures
• signed/notarized macOS distribution and native Windows/Linux qualification
• full Playwright/UI-driven E2E coverage
• additional locales beyond the shipped zh-CN catalog

Release constraint

Tag releases publish macOS arm64, Windows x64, and Linux x64 artifacts (D126 lifts the original D010 macOS-only constraint).

Rough effort (solo)

Milestone	Estimate
M0	done
M1	1-2 days
M2	2-4 days
M3	3-5 days
M4	3-5 days
M5	2-4 days
M6	done