ALTO Protocol

Required Folders

• runs/milestones.md — high-level architecture (orchestrator output)
• runs/decisions.md — architectural decisions (orchestrator output)
• runs/plan.md — detailed batch plan (planner output)
• runs/planning-config.json — planning configuration
• runs/state.json — protocol state
• runs/tasks/ — task files
• runs/handoffs/ — task completion handoffs

runs/state.json Schema

{
  "protocol": "alto-v1",
  "run_branch": "run/001",
  "phase": "ARCHITECTURE | PLANNING | IN_TASK | BETWEEN_TASKS | BLOCKED | COMPLETED | DEBUG",
  "current_task_id": "task-001",
  "current_role": "alto-backend",
  "current_handoff": "runs/handoffs/task-001.md",
  "completed_task_ids": [],
  "last_handoff": null,
  "estimated_tasks": 12,
  "replan_every": 4,
  "needs_architect": false,
  "updated_at": "ISO-8601"
}

Note: When setting current_task_id, also set current_handoff and pre-create the handoff template.

Phase Values

• ARCHITECTURE — orchestrator exploring codebase, designing milestones
• PLANNING — planner creating task files from milestones
• IN_TASK — role agent executing a task
• BETWEEN_TASKS — task complete, checking for replan or next task
• BLOCKED — human review required
• COMPLETED — all tasks done, awaiting human decision (debug or next feature)
• DEBUG — human testing, fixing issues before merge

runs/planning-config.json Schema

{
  "require_approval": true,
  "replan_strategy": "auto",
  "fixed_batch_size": 5,
  "architect_model": "opus",
  "planner_model": "opus"
}

runs/milestones.md Format (Orchestrator Output)

# Milestones

## Summary
Brief description of the feature and overall approach.

## Estimated Scope
- **Estimated tasks:** 12
- **Replan every:** 4 tasks
- **Complexity:** low | medium | high

## Milestones

### Milestone 1: <name>
- Description of what this milestone achieves
- Objective items addressed: 6.1, 6.2
- Estimated tasks: 3

### Milestone 2: <name>
- Description
- Objective items addressed: 6.3
- Estimated tasks: 4

## Key Decisions
See `runs/decisions.md` for detailed trade-offs.

runs/decisions.md Format (Orchestrator Output)

# Architectural Decisions

## Decision 1: <title>
**Context:** Why this decision was needed
**Options considered:**
1. Option A - pros/cons
2. Option B - pros/cons
**Decision:** Which option and why
**Consequences:** What this means for implementation

## Decision 2: <title>
...

Arbiter Checkpoint Folders

• runs/arbiter/config.json — thresholds
• runs/arbiter/state.json — last checkpoint metadata
• runs/arbiter/pending.json — snapshot triggering arbiter
• runs/arbiter/decision.json — arbiter output
• runs/arbiter/checkpoints/ — historical reports

Task File Format (runs/tasks/task-XXX.md)

Each task starts with YAML frontmatter:

---
task_id: task-001
title: Short human title
role: alto-backend | alto-frontend | alto-docs | alto-gitops | alto-qa
follow_roles: []            # optional: list of agent names to additionally obey
post: []                    # optional: list of agent names to run after role succeeds
depends_on: []              # optional
inputs:
  - runs/milestones.md
  - runs/handoffs/task-000.md
allowed_paths:
  - backend/**
handoff: runs/handoffs/task-001.md
---

Then Markdown body with:

• Goal
• Constraints (if any)
• Definition of Done (must be concrete)
• How to verify (tests to run, commands, manual checks)

Handoff Format (runs/handoffs/.md)

Required sections (validated by handoff-validate hook):

• ## Summary — what was done
• ## Files / ## Files Touched — list of modified files
• ## How to Verify / ## Verification — commands to validate

Optional sections:

• ## Interfaces — API/contract changes
• ## Next Steps — follow-up work or risks

Handoffs are validated on SubagentStop. Missing required sections block task completion.

Handoff Template (Pre-created by Orchestrator)

# Handoff: task-001

## Summary
<!-- What was accomplished -->

## Files Touched
<!-- List files modified -->

## How to Verify
<!-- Commands or manual checks -->

Role agents Edit this file (don't create from scratch). Path is in state.json → current_handoff.

Post-Agent Handoffs

Post-agents (alto-qa, code-simplifier, alto-gitops) write separate files by appending their suffix:

current_handoff: runs/handoffs/task-001.md

alto-qa         → runs/handoffs/task-001-qa.md
code-simplifier → runs/handoffs/task-001-simplifier.md
alto-gitops     → runs/handoffs/task-001-gitops.md

Post-agents read current_handoff from state.json and derive their path.

plan.md Format (Planner Output)

# Plan: <Feature Name> - Batch N

## Current Milestone
<Which milestone this batch addresses>

## Tasks in This Batch

| ID | Title | Role | Depends On |
|----|-------|------|------------|
| task-001 | ... | alto-backend | - |
| task-002 | ... | alto-frontend | task-001 |

## Implementation Notes
<Detailed implementation notes for this batch>

## Progress
- Milestones completed: 1/4
- Tasks completed: 3/12
- Objective items done: 2/8