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+# Understand Anything: Universal File Type Support
+
+**Date**: 2026-03-28
+**Status**: Approved
+**Approach**: Big Bang — all file types in one release
+
+## Goals
+
+1. Extend Understand Anything to analyze **any** file type, not just code
+2. Support both holistic project enrichment (non-code files enrich code graphs) and standalone analysis (docs-only repos, SQL schema collections, IaC projects)
+3. Maintain backward compatibility with existing code-only analysis
+
+## Supported File Types (26 new)
+
+### Documentation (3)
+
+| Type | Extensions | Parser | Node Types |
+|------|-----------|--------|------------|
+| Markdown | `.md`, `.mdx` | LLM + regex heading extraction | `document` |
+| reStructuredText | `.rst` | LLM | `document` |
+| Plain text | `.txt` | LLM | `document` |
+
+### Configuration (5)
+
+| Type | Extensions | Parser | Node Types |
+|------|-----------|--------|------------|
+| YAML | `.yaml`, `.yml` | `yaml` npm package | `config` |
+| JSON | `.json`, `.jsonc` | `JSON.parse` / `jsonc-parser` | `config`, `schema` |
+| TOML | `.toml` | `@iarna/toml` or similar | `config` |
+| .env | `.env`, `.env.*` | Regex line parser | `config` |
+| XML | `.xml` | LLM (optionally `fast-xml-parser`) | `config` |
+
+### Infrastructure & DevOps (7)
+
+| Type | Extensions | Parser | Node Types |
+|------|-----------|--------|------------|
+| Dockerfile | `Dockerfile`, `Dockerfile.*`, `.dockerfile` | Custom instruction parser | `service`, `pipeline` |
+| Docker Compose | `docker-compose.yml`, `compose.yml` | YAML parser + service extraction | `service` |
+| Terraform | `.tf`, `.tfvars` | Regex block parser | `resource` |
+| Kubernetes | K8s YAML (detected by `apiVersion` field) | YAML + kind detection | `service`, `resource` |
+| GitHub Actions | `.github/workflows/*.yml` | YAML + job/step extraction | `pipeline` |
+| Jenkinsfile | `Jenkinsfile` | LLM (Groovy DSL) | `pipeline` |
+| Makefile | `Makefile`, `*.mk` | Regex target parser | `pipeline` |
+
+### Data & Schema (6)
+
+| Type | Extensions | Parser | Node Types |
+|------|-----------|--------|------------|
+| SQL | `.sql` | Simple DDL parser | `table`, `endpoint` |
+| GraphQL | `.graphql`, `.gql` | Regex type/query parser | `schema`, `endpoint` |
+| OpenAPI/Swagger | `openapi.yaml`, `swagger.json` | YAML/JSON + path extraction | `endpoint`, `schema` |
+| Protocol Buffers | `.proto` | Regex message/service parser | `schema` |
+| JSON Schema | `*.schema.json` | JSON + `$ref`/`$defs` extraction | `schema` |
+| CSV/TSV | `.csv`, `.tsv` | Header row extraction | `table` |
+
+### Shell & Scripts (3)
+
+| Type | Extensions | Parser | Node Types |
+|------|-----------|--------|------------|
+| Shell | `.sh`, `.bash`, `.zsh` | Regex function parser | `file`, `function` |
+| PowerShell | `.ps1`, `.psm1` | LLM | `file`, `function` |
+| Batch | `.bat`, `.cmd` | LLM | `file` |
+
+### Markup (2)
+
+| Type | Extensions | Parser | Node Types |
+|------|-----------|--------|------------|
+| HTML | `.html`, `.htm` | LLM (tag structure) | `document` |
+| CSS/SCSS/Less | `.css`, `.scss`, `.less` | LLM | `file` |
+
+## Schema Extensions
+
+### New Node Types (8)
+
+Added to the existing `file | function | class | module | concept`:
+
+| Node Type | Purpose | Example |
+|-----------|---------|---------|
+| `config` | Configuration files and key settings | `package.json`, `tsconfig.json`, env vars |
+| `document` | Documentation, prose, guides | `README.md`, API docs |
+| `service` | Deployable services/containers | Docker containers, K8s Deployments |
+| `table` | Data tables, database objects | SQL tables, CSV datasets |
+| `endpoint` | API routes, queries, mutations | REST paths, GraphQL queries |
+| `pipeline` | CI/CD workflows, build steps | GitHub Actions jobs, Makefile targets |
+| `schema` | Type definitions for data interchange | Protobuf messages, JSON Schema |
+| `resource` | Infrastructure resources | Terraform resources, K8s ConfigMaps |
+
+### New Edge Types (8)
+
+Added to the existing 18 edge types:
+
+| Edge Type | Category | Meaning | Example |
+|-----------|----------|---------|---------|
+| `deploys` | Infrastructure | Service deploys code | Dockerfile -> app source |
+| `serves` | Infrastructure | Service exposes endpoint | K8s Service -> API endpoint |
+| `migrates` | Data flow | Migration modifies table | SQL migration -> table |
+| `documents` | Semantic | Doc describes code | README -> module |
+| `provisions` | Infrastructure | IaC creates resource | Terraform -> AWS resource |
+| `routes` | Behavioral | Routes traffic to service | nginx config -> service |
+| `defines_schema` | Data flow | Defines data shape | Protobuf -> endpoint |
+| `triggers` | Behavioral | Triggers pipeline/action | Git push -> GitHub Actions |
+
+### Schema Validation Auto-Fix Aliases
+
+New node type aliases:
+- `container` -> `service`, `migration` -> `table`, `workflow` -> `pipeline`
+- `route` -> `endpoint`, `doc` -> `document`, `setting` -> `config`, `infra` -> `resource`
+
+New edge type aliases:
+- `describes` -> `documents`, `creates` -> `provisions`, `exposes` -> `serves`
+
+## Plugin Architecture Changes
+
+### Generalized AnalyzerPlugin Interface
+
+```typescript
+interface AnalyzerPlugin {
+  name: string;
+  languages: string[];
+  analyzeFile(filePath: string, content: string): StructuralAnalysis;
+  resolveImports?(filePath: string, content: string): ImportResolution[];  // Now optional
+  extractCallGraph?(filePath: string, content: string): CallGraphEntry[];
+  extractReferences?(filePath: string, content: string): ReferenceResolution[];  // NEW
+}
+
+interface ReferenceResolution {
+  source: string;      // File making the reference
+  target: string;      // Referenced file or identifier
+  type: string;        // Reference type: "file", "image", "schema", "service"
+  line?: number;
+}
+```
+
+### Extended StructuralAnalysis
+
+```typescript
+interface StructuralAnalysis {
+  // Existing (unchanged)
+  functions: FunctionInfo[];
+  classes: ClassInfo[];
+  imports: ImportInfo[];
+  exports: ExportInfo[];
+  // New (all optional for backward compat)
+  sections?: SectionInfo[];      // Documents: headings, chapters
+  definitions?: DefinitionInfo[]; // Schemas: types, messages, tables
+  services?: ServiceInfo[];      // Infra: containers, deployments
+  endpoints?: EndpointInfo[];    // APIs: routes, queries
+  steps?: StepInfo[];            // Pipelines: jobs, stages, targets
+  resources?: ResourceInfo[];    // IaC: terraform resources, K8s objects
+}
+```
+
+### Custom Parsers (12)
+
+All lightweight — mostly regex-based, minimal dependencies:
+
+| Parser | Implementation | Extracts |
+|--------|---------------|----------|
+| `MarkdownParser` | Regex | Headings, links, code blocks, front matter |
+| `YAMLParser` | `yaml` npm | Key hierarchy, anchors, multi-doc |
+| `JSONParser` | Built-in `JSON.parse` | Key structure, `$ref`/`$defs` |
+| `TOMLParser` | `@iarna/toml` | Section structure |
+| `EnvParser` | Regex | Variable names and references |
+| `DockerfileParser` | Regex | FROM stages, EXPOSE ports, COPY sources |
+| `SQLParser` | Regex | CREATE TABLE/VIEW/INDEX, columns, foreign keys |
+| `GraphQLParser` | Regex | Types, queries, mutations, subscriptions |
+| `ProtobufParser` | Regex | Messages, services, enums, RPCs |
+| `TerraformParser` | Regex | Resources, modules, variables, outputs |
+| `MakefileParser` | Regex | Targets, dependencies, variables |
+| `ShellParser` | Regex | Functions, sourced files |
+
+## Agent Pipeline Changes
+
+### Project Scanner
+
+1. Scan ALL file types (remove code-only filter)
+2. Tag each file with category: `code`, `config`, `docs`, `infra`, `data`, `script`, `markup`
+3. Smart batch grouping: keep related files together (e.g., Dockerfile + docker-compose.yml)
+
+### File Analyzer
+
+Type-aware prompt templates by category:
+
+- **Code**: Current behavior (functions, classes, imports, call graph)
+- **Config**: Extract key settings, what they configure, which code files they affect
+- **Documentation**: Extract sections, key concepts, which code components are documented
+- **Infrastructure**: Extract services, ports, volumes, dependencies, which code they deploy
+- **Data/Schema**: Extract tables, columns, types, relationships, which code consumes this data
+- **Pipelines**: Extract jobs, steps, triggers, which code/infra they build/deploy
+
+### Cross-Type Reference Resolution
+
+Post-analysis step connecting:
+- Dockerfile `COPY` -> source code directories
+- CI config `run: npm test` -> test files
+- K8s manifest `image:` -> Dockerfile
+- SQL foreign keys -> other tables
+- OpenAPI `$ref` -> schema definitions
+- Markdown links -> referenced files
+
+### Architecture Analyzer
+
+New pattern detection:
+- Deployment topology: Dockerfile -> compose -> K8s chain
+- Data flow: Schema -> migration -> API endpoint -> client code
+- Documentation coverage: which modules have docs vs. not
+- Configuration dependency: which config files affect which code paths
+
+### Tour Builder
+
+Include non-code tour stops:
+- Project README overview
+- Dockerfile containerization
+- SQL migration database schema
+- CI/CD pipeline explanation
+
+## Dashboard Visualization
+
+### New Node Visual Styles
+
+| Node Type | Shape | Color | Icon |
+|-----------|-------|-------|------|
+| `config` | Rounded rect | Teal (#5eead4) | Gear |
+| `document` | Rounded rect | Sky blue (#7dd3fc) | Document |
+| `service` | Hexagon | Violet (#a78bfa) | Container/Box |
+| `table` | Rectangle | Emerald (#6ee7b7) | Grid |
+| `endpoint` | Pill/Stadium | Orange (#fdba74) | Arrow-right |
+| `pipeline` | Rounded rect | Rose (#fda4af) | Play/Workflow |
+| `schema` | Diamond | Amber (#fcd34d) | Blueprint |
+| `resource` | Cloud shape | Indigo (#a5b4fc) | Cloud |
+
+### Graph Layout
+
+1. Layer grouping by category — non-code nodes cluster separately from code nodes
+2. Legend update with 8 new node types
+3. Filter controls — checkboxes to show/hide each file category
+
+### Sidebar Enhancements
+
+NodeInfo panel updates per node type:
+- **Config**: key-value pairs, referencing code files
+- **Document**: heading outline, linked code components
+- **Service**: ports, volumes, dependencies, deployed code
+- **Table**: columns, types, foreign key relationships
+- **Endpoint**: HTTP method, path, request/response schema
+- **Pipeline**: jobs, triggers, deployed targets
+- **Schema**: fields, nested types, consumers
+- **Resource**: provider, type, dependencies
+
+ProjectOverview panel: add "File Types" breakdown (code vs. non-code distribution).
+
+## New Dependencies
+
+- `yaml` — YAML parsing (already common, ~50KB)
+- `@iarna/toml` — TOML parsing (~30KB)
+- `jsonc-parser` — JSON with comments (~20KB)
+
+No tree-sitter WASM additions. All other parsers are regex-based with zero dependencies.
+
+## Backward Compatibility
+
+- All new `StructuralAnalysis` fields are optional
+- `resolveImports` becomes optional on `AnalyzerPlugin`
+- Existing `LanguageConfig` entries unchanged
+- Schema validation auto-fixes new type aliases
+- Existing knowledge graphs remain valid (new types are additive)