[Gastown] PR 13: Molecule/Formula System

[jrf0110]

Parent: #204 | Phase 2: Multi-Agent Orchestration

No major architectural changes — molecules work the same in the container model. Tool calls go through the same DO RPCs.

Goal

Multi-step workflows so polecats can self-navigate through complex tasks.

Molecule Lifecycle

1. Work bead is created with a formula (JSON step definitions)
2. On sling, the Rig DO creates a molecule record with current_step = 0
3. gt_mol_current returns the current step
4. gt_mol_advance closes current step, increments to next
5. When all steps are closed, the molecule is complete → triggers gt_done equivalent

New Tools (added to plugin)

Tool	Description
gt_mol_current	Get current molecule step (title, instructions, step N of M)
gt_mol_advance	Complete current step with summary, advance to next

Rig DO Changes

• Molecule CRUD methods
• Step advancement logic with validation
• Auto-trigger done flow when final step completes
• Molecule status tracking (active, completed, failed)

Formula Format

{
  "steps": [
    { "title": "Set up database schema", "instructions": "Create the migration..." },
    { "title": "Implement API endpoints", "instructions": "Add REST endpoints for..." },
    { "title": "Write tests", "instructions": "Add unit tests covering..." }
  ]
}

Dependencies

• PR 1 (Rig DO — molecules table)
• PR 3 (Tool Plugin — new tools)

Acceptance Criteria

• Molecule CRUD in Rig DO
• gt_mol_current and gt_mol_advance tools in plugin
• Step advancement with validation (can't skip, can't go back)
• Auto-done on final step completion
• Formula JSON schema defined and validated
• Sling mutation updated to support molecule creation

[jrf0110]

Implemented in PR #389 (Phase 2). Molecule CRUD in Rig DO, gt_mol_current and gt_mol_advance plugin tools, auto-completion on final step.