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+# Multi-Platform Skill Support — Simplified Design
+
+**Date**: 2026-03-18
+**Status**: Approved
+**Goal**: Make Understand-Anything skills work across Codex, OpenClaw, OpenCode, and Cursor with zero build step — same files everywhere.
+
+## Design Principles
+
+Follows the [obra/superpowers](https://github.com/obra/superpowers) pattern:
+1. **Same files, all platforms** — no template markers, no build step, no platform-specific variants
+2. **`model: inherit`** — agents use the parent session's model, making them platform-agnostic
+3. **AI-driven installation** — `.{platform}/INSTALL.md` files that the AI agent reads and executes
+4. **Self-contained skills** — pipeline prompt templates live inside the skill directory, not in a separate `agents/` folder
+
+## Change 1: Move Pipeline Agents Into Skill
+
+The 5 pipeline agents (project-scanner, file-analyzer, architecture-analyzer, tour-builder, graph-reviewer) are used exclusively by the `/understand` skill. They become prompt templates co-located with the skill:
+
+**Before:**
+```
+agents/
+  project-scanner.md          # agent definition
+  file-analyzer.md
+  architecture-analyzer.md
+  tour-builder.md
+  graph-reviewer.md
+skills/understand/
+  SKILL.md                    # dispatches named agents
+```
+
+**After:**
+```
+skills/understand/
+  SKILL.md                           # dispatches subagents using templates
+  project-scanner-prompt.md          # prompt template (no agent frontmatter)
+  file-analyzer-prompt.md
+  architecture-analyzer-prompt.md
+  tour-builder-prompt.md
+  graph-reviewer-prompt.md
+```
+
+The prompt template files retain the full instruction content but drop the agent frontmatter (`name`, `tools`, `model`). The `SKILL.md` dispatch changes from "Dispatch the **project-scanner** agent" to "Dispatch a subagent using the template at `./project-scanner-prompt.md`".
+
+### Context Cost
+
+Reading templates through the main session adds ~11K tokens total (~5.5% of 200K context). This is sequential (one template at a time), and context compression reclaims earlier content. Acceptable trade-off for portability.
+
+## Change 2: New Registered Agent — knowledge-graph-guide
+
+Create a reusable agent that any skill or user can invoke to work with knowledge graphs:
+
+```yaml
+# agents/knowledge-graph-guide.md
+---
+name: knowledge-graph-guide
+description: |
+  Use this agent when users need help understanding, querying, or working
+  with an Understand-Anything knowledge graph. Guides users through graph
+  structure, node/edge relationships, layer architecture, tours, and
+  dashboard usage.
+model: inherit
+---
+```
+
+This agent knows:
+- The KnowledgeGraph JSON schema (nodes, edges, layers, tours)
+- The 5 node types and 18 edge types
+- How to navigate and query the graph
+- How to use the interactive dashboard
+- How to interpret architectural layers and guided tours
+
+## Change 3: Platform Installation Files
+
+Each platform gets an `INSTALL.md` that the AI agent can fetch and follow:
+
+| File | Platform | Install Mechanism |
+|------|----------|-------------------|
+| `.codex/INSTALL.md` | Codex | `git clone` + symlink to `~/.agents/skills/` |
+| `.opencode/INSTALL.md` | OpenCode | Plugin config in `opencode.json` |
+| `.openclaw/INSTALL.md` | OpenClaw | `git clone` + symlink to `~/.openclaw/skills/` |
+| `.cursor/INSTALL.md` | Cursor | `git clone` + symlink to `.cursor/plugins/` |
+
+User tells the agent one line:
+```
+Fetch and follow instructions from https://raw.githubusercontent.com/Lum1104/Understand-Anything/refs/heads/main/.codex/INSTALL.md
+```
+
+The agent executes the clone + symlink/config automatically.
+
+## Change 4: README Update
+
+Add a "Multi-Platform Installation" section to README.md with one-liner per platform.
+
+## File Summary
+
+| Action | Files |
+|--------|-------|
+| Delete | `agents/project-scanner.md`, `agents/file-analyzer.md`, `agents/architecture-analyzer.md`, `agents/tour-builder.md`, `agents/graph-reviewer.md` |
+| Create | `skills/understand/project-scanner-prompt.md`, `skills/understand/file-analyzer-prompt.md`, `skills/understand/architecture-analyzer-prompt.md`, `skills/understand/tour-builder-prompt.md`, `skills/understand/graph-reviewer-prompt.md` |
+| Create | `agents/knowledge-graph-guide.md` |
+| Create | `.codex/INSTALL.md`, `.opencode/INSTALL.md`, `.openclaw/INSTALL.md`, `.cursor/INSTALL.md` |
+| Modify | `skills/understand/SKILL.md` (dispatch references) |
+| Modify | `README.md` (multi-platform section) |
+
+## What We Don't Need
+
+- ~~`platforms/platform-config.json`~~ — same files everywhere
+- ~~`platforms/build.mjs`~~ — no build step
+- ~~`{{MARKER}}` template markers~~ — no templating
+- ~~`scripts/install-*.sh`~~ — AI agent follows INSTALL.md
+- ~~`dist-platforms/`~~ — no generated output
+
+## Platform Compatibility
+
+| Platform | Install Method | Agent Discovery | Skill Discovery |
+|----------|---------------|-----------------|-----------------|
+| Claude Code | Marketplace (existing) | `agents/` dir | `skills/` dir |
+| Codex | INSTALL.md → symlink | N/A (templates in skill) | `~/.agents/skills/` |
+| OpenCode | INSTALL.md → plugin config | N/A (templates in skill) | Plugin auto-registers |
+| OpenClaw | INSTALL.md → symlink | N/A (templates in skill) | `~/.openclaw/skills/` |
+| Cursor | INSTALL.md → symlink | `agents/` dir | `.cursor/plugins/` |