Kaiord — Open-Source Health & Fitness Data Framework

kaiord.com | Editor | npm

Kaiord is an open-source framework for creating, converting, and managing health & fitness data.

It provides:

• @kaiord/core: a TypeScript library with format adapters for .fit, .tcx, .zwo, and .krd (Kaiord) files, plus Garmin Connect API integration.

• @kaiord/cli: a command-line tool to convert, validate, and compare files across formats.

• @kaiord/mcp: an MCP server exposing Kaiord tools to AI agents (Claude Desktop, Claude Code, etc.). Published in the official MCP registry as io.github.pablo-albaladejo/kaiord.

• Workout Editor: a web application to create and edit workout files visually.

✨ Features

• Visual Workout Editor - Create and edit workouts in your browser

• Unified JSON-based format .krd (Kaiord Representation Definition)

• Schema validation (Zod)

• Round-trip safe conversions between FIT / TCX / ZWO / GCN / KRD

• Hexagonal architecture & fully typed API

Supported FIT Fields

Workout Metadata

• Sub-sport categorization: Detailed sport types (trail running, indoor cycling, lap swimming, etc.)

• Pool dimensions: Pool length and unit for swimming workouts

Workout Steps

• Coaching notes: Instructional text for each step (max 256 characters)

• Swimming equipment: Fins, kickboard, paddles, pull buoy, snorkel

Duration Types

• Time & distance: Standard interval durations

• Calorie-based: Steps ending after burning specified calories

• Power-based: Steps ending based on power thresholds (watts)

• Heart rate conditionals: Steps ending based on HR thresholds (bpm)

• Repeat conditionals: Repeat blocks until time/distance/calories/HR/power targets reached

Known Limitations

• Training Stress Score (TSS): The training_peaks_tss duration type is not yet implemented in the FIT converter. This is a TrainingPeaks-specific metric that requires additional mapping logic. Contributions welcome!

Related MCP server: intervals-mcp

🔒 Local-first architecture

Kaiord is local-first: your data lives on your device, because there is no Kaiord server to send it to. There are no accounts and no backend.

• Storage is your browser's IndexedDB. The Workout Editor persists every workout, template, profile, and setting in a local Dexie.js / IndexedDB database (new KaiordDatabase() in dexie-database.ts), and the UI reads it reactively through useLiveQuery. Nothing is written to a remote database — see the "Persisted data → Dexie" rule in State Management.

• Conversions run entirely on your machine. FIT / TCX / ZWO / GCN ↔ KRD conversion happens in-process — client-side in the editor (import-workout-formats.ts, export-workout-formats.ts) or locally in the @kaiord/cli. Files never leave your device to be converted.

• Sync is opt-in and goes to your cloud. Data leaves the device only if you connect Google Drive. The cloud-sync adapter uses the Google Identity Services drive.appdata scope, so synced data lands in your own Drive's app folder; the access token lives only in memory for the session and is never persisted by Kaiord.

• Integrations use your logged-in session — no credential proxy. Garmin, WHOOP, and Train2Go connect through browser-extension "bridges" (garmin-bridge, whoop-bridge, train2go-bridge) that piggyback on your existing browser session. Per openspec/specs/adapter-contracts/spec.md, a bridge "SHALL NOT store, transmit, or manage user credentials"; authentication is "delegated entirely to the browser's cookie jar." No third-party server proxies your credentials or your data.

• Works offline. Because all logic and storage are client-side, the editor keeps working with no network connection once loaded.

📚 Documentation

Comprehensive documentation is available in the /docs directory:

• Getting Started - Installation, basic usage, and quick examples for both library and CLI

• Architecture - Hexagonal architecture, ports & adapters pattern, and design principles

• Testing - Testing strategy, TDD workflow, and coverage requirements

• Deployment - CI/CD pipeline, GitHub Pages deployment, and npm publishing

• Contributing - Contribution guidelines, development workflow, and code standards

• KRD Format - Complete specification of the Kaiord Representation Definition format

• AI Agents - Guidance for AI-assisted development

🧩 Tech Stack

🏗 Monorepo Layout

kaiord/
├─ packages/
│  ├─ core/                → domain types, schemas, ports & use cases
│  ├─ fit/                 → Garmin FIT format adapter
│  ├─ tcx/                 → Training Center XML adapter
│  ├─ zwo/                 → Zwift ZWO format adapter
│  ├─ garmin/              → Garmin Connect API adapter
│  ├─ cli/                 → command-line interface
│  ├─ mcp/                 → MCP server for AI/LLM integration
│  └─ workout-spa-editor/  → web application (https://kaiord.com/editor/)
├─ docs/   → documentation
├─ LICENSE
├─ README.md
└─ pnpm-workspace.yaml

🚀 Quick Start

Try the Web App

Launch Workout Editor →

Create and edit workouts visually in your browser. No installation required.

Use the Library

pnpm install
pnpm -r build
pnpm -r test

# Example usage
pnpm kaiord --help

For detailed installation instructions and usage examples, see the Getting Started Guide.

🚀 CI/CD Pipeline

Kaiord uses GitHub Actions for continuous integration and deployment:

• Automated Testing: Multi-version testing on Node.js 22.x (Maintenance LTS) and 24.x (Active LTS)

• Code Quality: ESLint, Prettier, and TypeScript strict mode validation

• Release Automation: Changesets for version management and npm publishing

• Security: Weekly dependency vulnerability audits, CodeQL static analysis, and automated dependency updates

For complete CI/CD documentation, deployment guides, and npm publishing instructions, see Deployment.

Mechanical invariant guards

Beyond linting, the repo enforces its architecture and conventions with 60+ purpose-built guard scripts under scripts/, each with its own co-located test suite. They run on every commit (husky pre-commit) and in CI (pnpm test:scripts), and cover, among others:

• Hexagonal architecture — layer purity, adapter isolation, and the packages/core/src/ directory allowlist (check-architecture.mjs)

• Package dependency graph — every @kaiord/* dependency must match the spec table (check-package-deps.mjs)

• Test conventions — should -prefixed titles and Arrange/Act/Assert structure on every test (check-test-title-should.mjs, check-test-aaa.mjs)

• Privacy — no runtime values interpolated into toasts or console logs (check-no-pii-leakage.mjs)

• State discipline — no Zustand store writes persistence directly (check-no-zustand-writethrough.mjs)

• Spec hygiene — OpenSpec format, archive dates, and auto-generated indexes stay in sync (check-spec-format.mjs, check-archive-*.mjs)

If a rule matters here, a script enforces it — documentation describes the rules, but the guards are what make them true.

Contributing

To contribute to Kaiord:

1. Fork and clone the repository

2. Create a feature branch: git checkout -b feature/my-feature

3. Make your changes following the code style guidelines

4. Add a changeset: pnpm exec changeset (for version-worthy changes)

5. Test locally: pnpm -r test and pnpm -r build

6. Submit a PR: All checks must pass before merging

For detailed contribution guidelines, development workflow, and code standards, see Contributing.

📚 References & Resources

Format Specifications

• Garmin FIT SDK (JavaScript) - Official FIT protocol implementation

• FIT Workout Files Cookbook - Guide to encoding workout files

• FIT File Types: Workout - Workout file type specification

• Training Center XML (TCX) - Garmin's XML-based format

• TCX Schema (XSD) - Official Garmin TCX schema definition

• Zwift Workout Format (ZWO) - Zwift's XML-based workout format

❤️ Support

If you find Kaiord useful, consider supporting its development:

• ⭐ Star this repo to help others discover it

• 💖 Sponsor on GitHub

• ☕ Buy me a coffee

Your support helps maintain and improve Kaiord for the fitness community!

Built by Pablo Albaladejo

📜 License

MIT © 2025 Pablo Albaladejo See LICENSE for details.