Skip to content
SPECIFICTION
Get listed

RCS-Box

rcs.jetzt

From €49/mo Free plan WebAPI
Visit rcs.jetzt
Spec score 8.6 #3 of 34 in RCS Messaging Platforms

What it is

RCS-Box is a multi-tenant API for Google RCS Business Messaging, with EU hosting and a German contract partner. It supports text with suggestions, rich cards, carousels, XL messages, and automatic video and image unfurling. Webhooks can deliver incoming messages and opt-in or opt-out events; forwarded webhooks carry an HMAC-SHA256 signature calculated with the tenant API key. Each tenant has a dedicated key and brand-level isolation, plus a configurable country allowlist that defaults to Germany with the +49 prefix. The API manages STOP and START blacklist status per agent. Plans can use standard or newsletter mode, with newsletter billing based on active recipients per month. XL messages are available in all plans from Skizze and count as one conversation. The Free plan costs nothing and includes 100 sessions per calendar month. Skizze costs €49 a month, Atelier €249 a month, and Manufaktur €999 a month. The API is presented for development teams and technology leaders in startups, scale-ups, and enterprise technology units.

Spec sheet

What it does
RCS-Box is a multi-tenant API gateway for Google RCS Business Messaging.Read 15 Oct 2026 · api.box.rcs.jetzt
Audience
The API is presented for development teams, CTOs, and tech leads in startups, scale-ups, and enterprise technology units.Read 30 Sep 2026 · railslove.com
Headquarters
Cologne, GermanyRead 28 Sep 2026 · rcs.jetzt
Agent lifecycle
Agents can be created, updated, verified, launched and monitored through documented endpoints.Read 15 Oct 2026 · api.box.rcs.jetzt
Asset limits
Uploaded logo and hero assets accept PNG or JPEG files up to 5 MB, with a maximum of 50 assets per tenant.Read 15 Oct 2026 · api.box.rcs.jetzt
Authentication
Authenticated API calls use a tenant-specific 64-character hexadecimal key through Bearer or X-API-Key headers.Read 15 Oct 2026 · api.box.rcs.jetzt
Brand isolation
Each tenant receives brand-level isolation and a dedicated API key.Read 15 Oct 2026 · api.box.rcs.jetzt
Capability checks
The API checks RCS reachability and reported device features for individual numbers or batches of up to 100.Read 15 Oct 2026 · api.box.rcs.jetzt
Carousel limit
A carousel can contain up to ten cards.Read 15 Oct 2026 · railslove.com
Company founded
LinkedIn lists Railslove as founded in 2008.Read 15 Oct 2026 · de.linkedin.com
Company founders
Crunchbase names Jan Kus, Michael Bumann and Tim Schneider as Railslove founders.Read 15 Oct 2026 · crunchbase.com
Company funding
Crunchbase displays placeholder or obfuscated funding-event entries and no usable funding total.Read 15 Oct 2026 · crunchbase.com
Company headquarters
LinkedIn lists Railslove's headquarters in Cologne, North Rhine-Westphalia, Germany.Read 15 Oct 2026 · de.linkedin.com
Company legal name
The legal operator identified in the imprint is Railslove GmbH.Read 15 Oct 2026 · railslove.com
Company ownership
Crunchbase describes Railslove GmbH as a private, for-profit software development company.Read 15 Oct 2026 · crunchbase.com
Company size
LinkedIn lists Railslove in the 11–50 employee range.Read 15 Oct 2026 · de.linkedin.com
Country allowlist
Each tenant has a configurable country allowlist, defaulting to Germany with the +49 prefix.Read 30 Sep 2026 · api.box.rcs.jetzt
Country restriction
Each tenant has a configurable country allow-list that defaults to the +49 prefix.Read 15 Oct 2026 · api.box.rcs.jetzt
Documentation
The public documentation provides OpenAPI/Swagger navigation, endpoint examples, schemas, errors, webhooks and changelog information.Read 15 Oct 2026 · api.box.rcs.jetzt
Hosting
Railslove describes RCS-Box as EU-hosted with a German contract partner.Read 15 Oct 2026 · railslove.com
Image requirements
Google requires agent logos at 224×224 pixels and hero images at 1440×448 pixels with specified size caps.Read 15 Oct 2026 · api.box.rcs.jetzt
Independent company profile
ContactOut classifies Railslove as a computer-software company with 11–50 employees and a Cologne headquarters.Read 15 Oct 2026 · contactout.com
Independent headcount estimate
LeadIQ estimated Railslove at approximately 18 employees in September 2025.Read 15 Oct 2026 · leadiq.com
Limit: carrier dependence
Agent launch status is tracked per carrier and can be pending, rejected or suspended by carrier review.Read 15 Oct 2026 · api.box.rcs.jetzt
Limit: country coverage
Numbers outside a tenant's configured country prefixes are rejected by the send endpoint.Read 15 Oct 2026 · api.box.rcs.jetzt
Limit: pre-launch sending
An agent in draft or another pre-launch state cannot message general recipients until launch and is restricted to accepted testers.Read 15 Oct 2026 · api.box.rcs.jetzt
Message types
The API supports text, suggested actions, rich cards, carousels, files, images and videos.Read 15 Oct 2026 · api.box.rcs.jetzt
Messaging formats
It supports text with suggestions, rich cards, carousels, XL messages, and automatic video and image unfurling.Read 30 Sep 2026 · railslove.com
Newsletter mode
Tenants can choose standard billing or newsletter billing based on active recipients per month.Read 15 Oct 2026 · railslove.com
Notable news: Fortuna launch
Fortuna Köln announced its Railslove-built RCS fan newsletter on 11 August 2025.Read 15 Oct 2026 · fortuna-koeln.de
Opt-out handling
STOP and START keyword processing maintains a per-agent blacklist and forwards consent events for acknowledgement.Read 15 Oct 2026 · api.box.rcs.jetzt
Praise: no app required
Fortuna Köln says its RCS newsletter reaches fans in the existing messaging app without an additional download.Read 15 Oct 2026 · fortuna-koeln.de
Product type
RCS-Box is a multi-tenant API for Google RCS Business Messaging.Read 30 Sep 2026 · api.box.rcs.jetzt
Public code presence
Railslove's GitHub organization exposes public repositories, including projects marked LGPL-3.0 and MIT, but those repositories are not identified as RCS-Box.Read 15 Oct 2026 · github.com
Rate-limit behavior
Authenticated v1 endpoints are not tenant-rate-limited, while public analytics ingestion is limited to 120 requests per minute per IP.Read 15 Oct 2026 · api.box.rcs.jetzt
SDK availability
The opened developer documentation describes a JSON REST API with cURL examples and does not list official SDK packages.Read 15 Oct 2026 · api.box.rcs.jetzt
Security claim
Railslove markets the service as DSGVO-compliant and running on German infrastructure.Read 15 Oct 2026 · railslove.com
Tenant isolation
The API provides brand-level isolation with dedicated API keys per tenant.Read 30 Sep 2026 · api.box.rcs.jetzt
Tester management
Pre-launch agents can send only to testers who accepted Google's invitation workflow.Read 15 Oct 2026 · api.box.rcs.jetzt
Webhook security
Forwarded webhook bodies are signed with an HMAC-SHA256 value using the tenant API key.Read 15 Oct 2026 · api.box.rcs.jetzt
Webhooks
RCS-Box forwards incoming messages, delivery events and opt-in or opt-out events to a configured webhook URL.Read 15 Oct 2026 · api.box.rcs.jetzt
XL messages
XL Messages send two or three messages in sequence and are available from the Skizze plan upward.Read 15 Oct 2026 · railslove.com

Plans and prices

Free Free Free tier · API access Read 15 Oct 2026 · railslove.com
Free Free 100 sessions per calendar month Read 30 Sep 2026 · api.box.rcs.jetzt
Skizze €49 a month monthly XL Messages · Standard or Newsletter mode Read 15 Oct 2026 · railslove.com
Atelier €249 a month monthly XL Messages · Standard or Newsletter mode Read 15 Oct 2026 · railslove.com
Manufaktur €999 a month monthly XL Messages · Standard or Newsletter mode Read 15 Oct 2026 · railslove.com

Every RCS-Box plan and price →

Strong points and limits

Strong points

  • Supports rich cards, carousels, and XL messages
  • Webhooks cover incoming and opt-in/out events
  • Provides brand-level isolation with tenant API keys
  • Automatically handles STOP and START status
  • Free plan includes 100 sessions per calendar month

Limits

  • Free plan is limited to 100 monthly sessions
  • Paid plans start at €49 a month
  • Country allowlist defaults to Germany’s +49 prefix

Who it suits

RCS-Box is aimed at development teams, CTOs, and tech leads in startups, scale-ups, and enterprise technology units. Its tenant-level keys, allowlists, and webhooks are relevant to teams integrating RCS messaging into their systems.

Verdict

RCS-Box provides tenant-separated access to RCS messaging with several message formats and webhook events. Newsletter mode bills by active recipients per month, while the listed Free plan is limited to 100 sessions monthly.

Where Specifiction places it

Alternatives to RCS-BoxAll alternatives →