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+# Cross-SDK Feature Parity
+
+All SDKs must implement the same operations. When adding a feature to one SDK, implement it in all others (or open tracking issues).
+
+## Required TurboSign Operations
+
+| Operation | JS | Py | Go | PHP | Java |
+|---|---|---|---|---|---|
+| configure | `configure()` | `configure()` | `Configure()` | `configure()` | `configure()` |
+| createSignatureReviewLink | `createSignatureReviewLink()` | `create_signature_review_link()` | `CreateSignatureReviewLink()` | `createSignatureReviewLink()` | `createSignatureReviewLink()` |
+| sendSignature | `sendSignature()` | `send_signature()` | `SendSignature()` | `sendSignature()` | `sendSignature()` |
+| getStatus | `getStatus()` | `get_status()` | `GetStatus()` | `getStatus()` | `getStatus()` |
+| download | `download()` | `download()` | `Download()` | `download()` | `download()` |
+| void | `void()` | `void_document()` | `VoidDocument()` | `voidDocument()` | `voidDocument()` |
+| resend | `resend()` | `resend_email()` | `ResendEmail()` | `resend()` | `resendEmail()` |
+| getAuditTrail | `getAuditTrail()` | `get_audit_trail()` | `GetAuditTrail()` | `getAuditTrail()` | `getAuditTrail()` |
+
+## Required TurboPartner Operations
+
+- Organization CRUD: create, list, getDetails, update, delete
+- Organization entitlements: updateEntitlements
+- Organization users: list, add, update role, remove, resend invitation
+- Organization API keys: list, create, update, revoke
+- Partner API keys: list, create, update, revoke
+- Partner users: list, add, update permissions, remove, resend invitation
+- Audit logs: list with filtering
+
+## Naming Conventions by Language
+
+| Language | Methods | Classes | Files | Constants |
+|---|---|---|---|---|
+| JS/TS | camelCase | PascalCase | kebab-case | UPPER_SNAKE |
+| Python | snake_case | PascalCase | snake_case | UPPER_SNAKE |
+| Go | PascalCase (exported) | PascalCase | snake_case | PascalCase |
+| PHP | camelCase | PascalCase | PascalCase | UPPER_SNAKE |
+| Java | camelCase | PascalCase | PascalCase | UPPER_SNAKE |
+| Ruby | snake_case | PascalCase | snake_case | UPPER_SNAKE |
+
+## New SDK Checklist
+
+1. Create `packages/<lang>-sdk/` directory
+2. Implement TurboSign with all operations above
+3. Implement TurboPartner with all operations above
+4. Implement error hierarchy (TurboDocxError + 5 subtypes)
+5. Write tests matching parity of existing SDKs
+6. Add CI job to `.github/workflows/ci.yml`
+7. Add publish workflow `.github/workflows/publish-<lang>.yml`
+8. Create README with install, configure, and usage examples
diff --git a/.claude/rules/js-sdk.md b/.claude/rules/js-sdk.md
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+# JS/TS SDK Rules
+
+## Zero Runtime Dependencies
+
+The JS SDK has **no runtime dependencies** — only devDependencies (TypeScript, Jest, ts-jest, @types).
+Use native `fetch` (Node 18+ global) for HTTP. Use native `fs` and `path` for file operations.
+Never add runtime dependencies without explicit approval.
+
+## Static Class Pattern
+
+Both `TurboSign` and `TurboPartner` use static classes:
+```typescript
+TurboSign.configure({ apiKey, orgId, senderEmail });
+const result = await TurboSign.sendSignature({ ... });
+```
+No `new TurboSign()` — all methods are static. The `HttpClient` instance is held as a private static field.
+
+## TypeScript Configuration
+
+- **Strict mode**: `strict: true` in tsconfig
+- **Target**: ES2020
+- **Module**: commonjs
+- **Declaration files**: Generated in `dist/`
+- All public APIs must have TypeScript types — no `any` in public interfaces
+
+## senderEmail Validation
+
+`senderEmail` is **required** for TurboSign (not for TurboPartner). The HttpClient throws `ValidationError` if missing unless `skipSenderValidation: true` (used internally by TurboPartner).
+
+## File Type Detection
+
+Use **magic bytes** to detect file types, not file extensions:
+- PDF: bytes `0x25 0x50 0x44 0x46` (`%PDF`)
+- DOCX: bytes `0x50 0x4B` (`PK`) + contains `word/`
+- PPTX: bytes `0x50 0x4B` (`PK`) + contains `ppt/`
+
+## Response Unwrapping
+
+The `smartUnwrap` method strips the `{ data: ... }` wrapper when the response object has only a `data` key. This is automatic — module methods don't need to unwrap manually.
+
+## Testing
+
+- Framework: Jest + ts-jest
+- Run: `npm test` (from `packages/js-sdk/`)
+- Mock `global.fetch` — never make real HTTP calls in tests
+- Test files live in `packages/js-sdk/tests/`
diff --git a/.claude/rules/testing.md b/.claude/rules/testing.md
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+# Testing Rules
+
+## TDD Workflow
+
+1. Write tests first that describe expected behavior
+2. Run tests to confirm they fail
+3. Implement the feature to make tests pass
+4. Refactor while keeping tests green
+
+## Test Parity
+
+All SDKs must have equivalent test coverage. When adding a test case in one SDK, add the same scenario in all others. Tests should cover:
+- Successful operations (happy path)
+- Error handling (auth errors, validation, not found, rate limit)
+- Configuration (explicit config, env var fallback, missing required fields)
+- File input variants (buffer, path, URL, deliverableId)
+- Sender config behavior (senderEmail required, senderName optional)
+
+## Per-SDK Test Commands
+
+| SDK | Command | Framework |
+|---|---|---|
+| js-sdk | `npm test` | Jest + ts-jest |
+| py-sdk | `pytest -v` | pytest |
+| go-sdk | `go test -v ./...` | go test |
+| php-sdk | `composer test` | PHPUnit |
+| java-sdk | `mvn test -B` | JUnit (Maven Surefire) |
+| ruby-sdk | `bundle exec rspec` | RSpec |
+
+## Mock HTTP Responses, Not SDK Internals
+
+- Mock the HTTP layer (fetch/requests/http.Client), not SDK module methods
+- Return realistic response shapes matching the actual API
+- Test error mapping: mock HTTP 401 → verify AuthenticationError is thrown
+- Never make real HTTP calls in unit tests
+- Keep mocks minimal — only mock what's needed for the specific test case
diff --git a/CLAUDE.md b/CLAUDE.md
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+# TurboDocx SDK Monorepo
+
+Multi-language SDK monorepo for TurboDocx API (TurboSign digital signatures + TurboPartner portal management).
+
+## Directory Structure
+
+```
+packages/
+├── js-sdk/      # TypeScript/JavaScript (@turbodocx/sdk)
+├── py-sdk/      # Python (turbodocx-sdk)
+├── go-sdk/      # Go (github.com/TurboDocx/SDK/packages/go-sdk)
+├── php-sdk/     # PHP (turbodocx/sdk)
+├── java-sdk/    # Java (com.turbodocx:sdk)
+└── ruby-sdk/    # Ruby (turbodocx-sdk)
+.github/workflows/  # Per-SDK CI + publish workflows
+```
+
+## Build & Test Commands
+
+| SDK | Install | Build | Test |
+|-----|---------|-------|------|
+| js-sdk | `npm ci` | `npm run build` | `npm test` |
+| py-sdk | `pip install -e ".[dev]"` | — | `pytest -v` |
+| go-sdk | `go mod tidy` | — | `go test -v ./...` |
+| php-sdk | `composer install` | — | `composer test` |
+| java-sdk | — | `mvn compile` | `mvn test -B` |
+| ruby-sdk | `bundle install` | — | `bundle exec rspec` |
+
+Root-level shortcuts (JS only): `npm run build:js`, `npm run test:js`
+
+## Commit Format
+
+```
+feat|fix|docs|test|refactor: description
+[js-sdk] Add batch signing      # PR title format
+```
+
+## Cross-SDK Conventions
+
+- All SDKs must maintain **feature parity** — see `.claude/rules/cross-sdk-parity.md`
+- Two modules per SDK: **TurboSign** (signatures) and **TurboPartner** (partner portal)
+- Follow each language's idiomatic naming (camelCase JS, snake_case Py, PascalCase Go)
+- Shared error hierarchy: `TurboDocxError > Auth | Validation | NotFound | RateLimit | Network`
+- Config pattern: explicit config → env var fallback → error
+
+## Architecture
+
+See @docs/ARCHITECTURE.md for HTTP client design, file input abstraction, error handling, and CI/CD details.
+
+## Rules
+
+- `.claude/rules/cross-sdk-parity.md` — feature parity requirements
+- `.claude/rules/js-sdk.md` — JS/TS-specific conventions
+- `.claude/rules/testing.md` — TDD workflow and test patterns
diff --git a/docs/ARCHITECTURE.md b/docs/ARCHITECTURE.md
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+# SDK Architecture
+
+## Module Design
+
+Each SDK exposes two top-level modules:
+
+- **TurboSign** — digital signature operations (create review links, send signatures, void, resend, download, get status, audit trail)
+- **TurboPartner** — partner portal management (organizations, users, API keys, entitlements, audit logs)
+
+Modules use a **static class pattern**: configure once with `TurboSign.configure(config)`, then call static methods. No instantiation required.
+
+## HTTP Client
+
+Each SDK wraps a single `HttpClient` class responsible for:
+
+1. **Authentication**: Bearer token via `apiKey` or `accessToken`, sent in `Authorization` header. Org ID sent as `x-rapiddocx-org-id` header.
+2. **Base URL**: Configurable, defaults to `https://api.turbodocx.com`. Env var fallback: `TURBODOCX_BASE_URL`.
+3. **Response unwrapping**: Backend wraps responses in `{ "data": ... }`. The client auto-unwraps when the response has only a `data` key (smart unwrap).
+4. **Error mapping**: HTTP status codes map to typed errors (400→Validation, 401→Auth, 404→NotFound, 429→RateLimit, other→TurboDocxError).
+5. **File upload**: Multipart form upload with magic-byte file type detection.
+
+### Partner Client
+
+TurboPartner uses a separate config (`PartnerClientConfig`) with `partnerApiKey` (TDXP- prefix) and `partnerId`. It skips sender email validation since it doesn't send signature emails.
+
+## Configuration Pattern
+
+All SDKs follow: **explicit config > env var fallback > error**.
+
+| Config Field | Env Var | Required |
+|---|---|---|
+| `apiKey` | `TURBODOCX_API_KEY` | Yes (or accessToken) |
+| `orgId` | `TURBODOCX_ORG_ID` | Yes for TurboSign |
+| `senderEmail` | `TURBODOCX_SENDER_EMAIL` | Yes for TurboSign |
+| `senderName` | `TURBODOCX_SENDER_NAME` | No (defaults to "API Service User") |
+| `baseUrl` | `TURBODOCX_BASE_URL` | No (defaults to api.turbodocx.com) |
+
+## Error Hierarchy
+
+```
+TurboDocxError (base)
+├── AuthenticationError    (401)
+├── ValidationError        (400)
+├── NotFoundError          (404)
+├── RateLimitError         (429)
+└── NetworkError           (no status — fetch/connection failure)
+```
+
+All errors carry `statusCode` and `code` properties. Each SDK implements this hierarchy using language-appropriate patterns (classes in JS/Py/Java/PHP, error types in Go, exceptions in Ruby).
+
+## File Input Abstraction
+
+TurboSign methods accept documents via multiple input types:
+
+| Input | Description |
+|---|---|
+| `file` (Buffer/bytes) | Raw file content — type detected via magic bytes |
+| `file` (path string) | Local file path — read and detect type |
+| `file` (File object) | Browser File API object |
+| `fileLink` (URL) | Remote file URL — server fetches it |
+| `deliverableId` | TurboDocx-generated document ID |
+| `templateId` | Pre-configured TurboSign template |
+
+When a `file` is provided, the request uses multipart form upload. Otherwise, JSON body is used.
+
+### Magic Byte Detection
+
+File types are detected from content, not extensions:
+- `%PDF` (0x25504446) → PDF
+- `PK` (0x504B) + `word/` → DOCX
+- `PK` (0x504B) + `ppt/` → PPTX
+
+## Signature Field Positioning
+
+Fields use **coordinate-based positioning**:
+- `page` — page number (1-indexed)
+- `x`, `y` — position from top-left in points
+- `width`, `height` — field dimensions in points
+- `recipientEmail` — binds field to a specific signer
+- `type` — field type (`signature`, `initials`, `date`, `text`, etc.)
+
+## Type/Model Organization
+
+Each SDK organizes types by module:
+- `types/sign` — TurboSign request/response types (recipients, fields, document status)
+- `types/partner` — TurboPartner request/response types (organizations, users, API keys, audit logs)
+
+## CI/CD
+
+### Test Workflows (`.github/workflows/ci.yml`)
+Runs on push to `main`/`develop` and all PRs. Per-SDK jobs with language-specific setup:
+- JS: Node 22, `npm ci && npm run build && npm test`
+- Python: 3.9, `pip install -e ".[dev]" && pytest -v`
+- Go: 1.21, `go mod tidy && go test -v ./...`
+- PHP: 8.1, `composer install && composer test && composer phpstan`
+- Java: JDK 11 (Temurin), `mvn test -B`
+
+### Publish Workflows
+Separate workflow per SDK (`publish-{js,py,go,php,java}.yml`). Triggered on release or manual dispatch. Each publishes to the language's package registry.