AI Agents & App Builders - Opencals Developer Docs

Most Opencals integrations are now written inside an AI coding agent. Agent Skills give that agent ground-truth knowledge of the Opencals API and SDK — the real method names, argument shapes, and flows — so it builds working code instead of guessing. Skills follow the open Agent Skills standard (a folder with a SKILL.md), supported by Claude Code, Cursor, OpenAI Codex, Gemini CLI and more. They live in one public repo: github.com/letsopencals/skills.

The two skills

opencals-storefront-api

Ground truth for any code that talks to the Opencals API / SDK — availability, carts, appointments, checkout, discounts, customer accounts, guests & attendees, custom durations, reschedule/cancel, rate limits. Details →

opencals-build-booking-site

Build a whole booking website — pick an official template, scaffold, wire it up, rebrand, deploy. Uses the API skill for exact call shapes. Details →

The primary journey

Describe your business

Hand your agent a business idea and some inspiration — screenshots, a competitor site, a brand feel.

The agent builds it

opencals-build-booking-site picks the closest template and scaffolds it; opencals-storefront-api supplies the exact API calls to wire availability, booking and checkout.

Rebrand & deploy

The agent restyles to your inspiration and deploys to Vercel. You add your Opencals API key. Bookings, checkout and payments work out of the box.

Install

Claude Code
Cursor / Codex / Gemini
Any agent (manual)
v0 / Lovable / Base44

/plugin marketplace add letsopencals/skills
/plugin install opencals@opencals

Both skills load automatically and trigger on relevant requests.

Agent Skills are portable — a folder with a SKILL.md. Clone the repo and copy the skill folders into your tool’s skills directory:

git clone https://github.com/letsopencals/skills opencals-skills
# copy opencals-storefront-api/ and opencals-build-booking-site/
# into your agent's skills folder

The exact skills directory differs per tool — check your tool’s current Agent Skills / rules docs for where skill folders go.

Clone the repo and point your agent at the relevant SKILL.md:

Follow the skill in opencals-storefront-api/SKILL.md when writing Opencals API code, and opencals-build-booking-site/SKILL.md to scaffold a site.

Each AI app builder has its own setup, with every field ready to copy:

Lovable: a custom connector with two knowledge files.
v0: attach these skills from skills.sh (letsopencals/skills).
Base44: one backend function, an app secret and two workspace skills.

For other builders (Bolt, Replit), paste the API reference and booking-site playbook into the project instructions.

AI app builders

Lovable

Custom connector + knowledge files

v0

Opencals skills from skills.sh

Base44

Backend function + workspace skills

For AI agents reading this

The full documentation is available as machine-readable Markdown:

llms.txt

Structured index of every docs page.

llms-full.txt

The complete docs in one file for maximum context.

The API reference is generated from the OpenAPI spec — download it via the Download spec action, or fetch openapi.json directly.

​The two skills

opencals-storefront-api

opencals-build-booking-site

​The primary journey

​Install

​AI app builders

Lovable

v0

Base44

​For AI agents reading this

llms.txt

llms-full.txt

The two skills

The primary journey

Install

AI app builders

For AI agents reading this