Crescendo Lab

Crescendo Lab is a Taiwan-based, Asia-leading AI omnichannel customer communication software company (cresclab.com) serving 800+ global brands, and a LINE Biz-Solutions Gold Partner. Its platform spans MAAC (AI marketing automation), CAAC (conversational applications), and DAAC (data intelligence) across LINE, WhatsApp, SMS, email, and social channels. Its developer-facing surface is MAAC Go (sms.cresclab.com) — a self-serve, NCC-compliant Taiwan SMS API with a published OpenAPI spec, first-party Node/Python SDKs, a CLI, an official MCP server, and delivery webhooks. Surfaced as a 500 Global portfolio company and enriched into the API Evangelist network.

Crescendo Lab publishes 5 API contracts indexed on the APIs.io network, including Broadcast API, Contacts API, SMS API, and 2 more. Tagged areas include Company, SMS, Messaging, Marketing Automation, and Customer Engagement.

The Crescendo Lab catalog on APIs.io includes 1 event-driven AsyncAPI specification.

Crescendo Lab’s developer surface includes documentation, engineering blog, pricing, signup flow, CLI, API reference, getting-started guide, and 23 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

57.2/100 strong ▬ flat Agent 42/100 agent native Front door AI 6/6 dominant saas Full breakdown ↓
scored 2026-10-31 · rubric v0.25.0 · Show this score on your site →

AccessFreemiumSelf serveFree trial⚡ Free to try

1 published contract 1 MCP Servers 4 Agent Skills

Company SMS Messaging Marketing Automation Customer Engagement Taiwan Omnichannel MCP

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Application Communications

AE-150

Broadcast

POST /broadcast

Kin Score

Kin Score How this is scored →
scored 2026-10-31 · rubric v0.25.0

Composite quality — 57.2/100 · strong

Contract Quality 10.8 / 21

Developer Ergonomics 13.7 / 17

Access Clarity 14.3 / 17

Operational Transparency 3.8 / 11

Contract Governance 0.5 / 10

Discoverability 5.5 / 9

Regulatory Posture 3.1 / 15

Agent readiness — 42/100 · agent native

Machine-Readable Contract 18 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 9 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 6

Agent Skills 5 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

Regulatory Posture applies to this provider. Its tags matched the Telecommunications regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

Agentic Access Contract +10 pts — agentic_access artifact present (x-agentic-access), graded by author
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Delegated User Identity +6 pts — a served discovery document listing authorization_code in grant_types_supported (served), else an oauth2 authorizationCode flow or openIdConnect declared in an OpenAPI (documented)
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document
Documented Reversibility +6 pts — a reversal operation in the contract, graded up when a window is documented too
Agentic Commerce Well-Known Document +5 pts — a parsing /.well-known/ucp.json or acp.json declaring a version and at least one service — `self` when its endpoints are on the provider's own domain, `platform` when they are on a vendor's

4 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Contract Quality scores 50.9 — up to +12.3 composite points
Contract Governance scores 4.5 — up to +11.5 composite points
Operational Transparency scores 34.2 — up to +8.6 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/crescendo-lab/apis.yml: open an issue on github.com/api-evangelist/crescendo-lab to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Markets this provider is in provisional

The Kin Score Market layer reads a provider inside its market: its position, and how deep its integrations go. Depth is only comparable within a position. Provisional and unweighted: not part of the Kin Score or agent readiness.

Market	Position	Depth	Registered MCP server	Declares compatibility
Taiwan Listed Companies (TWSE, TPEx)	long-tail	2.5 (thin)	-	-

Registered MCP server and declares compatibility are report only — not weighted. Undeclared means we found nothing we can read, so there is no number: we never infer integrations.

APIs 5

Individual APIs this provider publishes, each with its own machine-readable definition.

Crescendo Lab Broadcast API

Bulk (1-to-many) SMS. Small batches dispatch inline; >30 recipients queue asynchronously.

Crescendo Lab Contacts API

Address book with NCC-consent tracking.

Crescendo Lab SMS API

Transactional (1-to-1) SMS send + status.

Crescendo Lab Teams API

Cost-attribution teams. Tag sends with a team to see which team sent/spent how much (shared wallet — reporting only, not a wallet split).

Crescendo Lab MAAC Go API

The MAAC Go API API from Crescendo Lab — 0 operation(s) for maac go api.

Open Collections 4

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

MAAC Go Broadcast API

OPEN COLLECTION

MAAC Go Broadcast Contacts API

OPEN COLLECTION

MAAC Go Broadcast SMS API

OPEN COLLECTION

MAAC Go Broadcast Teams API

OPEN COLLECTION

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

MAAC Go MCP

Official hosted + local MCP server for MAAC Go (Crescendo Lab's self-serve Taiwan SMS platform). Lets Claude / Cursor / Windsurf / Codex send SMS, run broadcasts, pull logs, and...

MCP SERVER

Agent Skills 4

Packaged agent skills for driving this provider's APIs from an AI assistant.

send-broadcast-campaign

AGENT SKILL

manage-contacts

AGENT SKILL

send-transactional-sms

AGENT SKILL

attribute-sms-cost-by-team

AGENT SKILL

Pricing Plans 2

Published pricing tiers and plan structures.

Crescendo Lab Plans Pricing

8 plans

PLANS

Crescendo Lab Price Estimates

0 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Crescendo Lab Rate Limits

2 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Crescendo Lab Finops

FINOPS

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Crescendo Lab Maacgo Webhooks

ASYNCAPI

OpenAPI Overlays 1

Overlays applied on top of this provider's contracts. Each card says who wrote it: a document the provider publishes, or one API Evangelist derived or generated.

Crescendo Lab Maacgo Overlay

4 actions · update · crescendo-lab-maacgo-openapi.yaml

GENERATED

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Crescendo Lab Authentication

http · 1 scheme

SECURITY

Crescendo Lab Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Resources

Get Started 5

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

SignUp

SignUp

Login

GettingStarted

GettingStarted

Sandbox

Sandbox

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 3

MCP servers, agent skills, and machine-readable catalogs

LLMsTxt

LLMsTxt

MCPServer

MCPServer

AgentSkill

AgentSkill

Design & Contract 2

Pagination, idempotency, versioning, errors, and events

Conventions

Conventions

Idempotency

Idempotency

Build 5

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

SDKs

Packages

CLI

ToolCrosswalk

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Operate 2

Status, limits, changes, and where to get help

HelpCenter

HelpCenter

RateLimits

RateLimits

Commercial 4

Pricing, plans, and the legal terms of use

Pricing

TermsOfService

PrivacyPolicy

Plans

Company 3

The organization behind the API

BlogRSS

BlogRSS

Website

Website

Blog

Blog

Other 2

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

Overlay

Overlay

Source (apis.yml)

aid: crescendo-lab
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: true
  try_now: true
  public: false
  label: Freemium (free trial) · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  - rate-limits
  - security
  - sandbox
  generated: '2026-09-03'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/crescendo-lab.png
name: Crescendo Lab
description: Crescendo Lab is a Taiwan-based, Asia-leading AI omnichannel customer communication software company (cresclab.com)
  serving 800+ global brands, and a LINE Biz-Solutions Gold Partner. Its platform spans MAAC (AI marketing automation), CAAC
  (conversational applications), and DAAC (data intelligence) across LINE, WhatsApp, SMS, email, and social channels. Its
  developer-facing surface is MAAC Go (sms.cresclab.com) — a self-serve, NCC-compliant Taiwan SMS API with a published OpenAPI
  spec, first-party Node/Python SDKs, a CLI, an official MCP server, and delivery webhooks. Surfaced as a 500 Global portfolio
  company and enriched into the API Evangelist network.
url: https://raw.githubusercontent.com/api-evangelist/crescendo-lab/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- 500-global
x-tier: enriched
x-tier-reason: portfolio-lead-enriched
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-10-06'
tags:
- Company
- SMS
- Messaging
- Marketing Automation
- Customer Engagement
- Taiwan
- Omnichannel
- MCP
apis:
- aid: crescendo-lab:crescendo-lab-broadcast-api
  name: Crescendo Lab Broadcast API
  description: Bulk (1-to-many) SMS. Small batches dispatch inline; >30 recipients queue asynchronously.
  humanURL: https://sms.cresclab.com/developers.html
  baseURL: https://sms.cresclab.com/api
  tags:
  - Broadcast
  properties:
  - type: OpenAPI
    url: openapi/crescendo-lab-broadcast-api-openapi.yml
  - type: Webhooks
    url: asyncapi/crescendo-lab-maacgo-webhooks.yml
  - type: ErrorCatalog
    url: errors/crescendo-lab-problem-types.yml
  - type: Lifecycle
    url: lifecycle/crescendo-lab-lifecycle.yml
  - type: Conformance
    url: conformance/crescendo-lab-conformance.yml
  - type: DataModel
    url: data-model/crescendo-lab-data-model.yml
  - type: Sandbox
    url: sandbox/crescendo-lab-sandbox.yml
  - type: Documentation
    url: https://sms.cresclab.com/developers.html#api
  - type: APIReference
    url: https://sms.cresclab.com/openapi.yaml
  - type: GettingStarted
    url: https://sms.cresclab.com/developers.html
- aid: crescendo-lab:crescendo-lab-contacts-api
  name: Crescendo Lab Contacts API
  description: Address book with NCC-consent tracking.
  humanURL: https://sms.cresclab.com/developers.html
  baseURL: https://sms.cresclab.com/api
  tags:
  - Contacts
  properties:
  - type: OpenAPI
    url: openapi/crescendo-lab-contacts-api-openapi.yml
  - type: Webhooks
    url: asyncapi/crescendo-lab-maacgo-webhooks.yml
  - type: ErrorCatalog
    url: errors/crescendo-lab-problem-types.yml
  - type: Lifecycle
    url: lifecycle/crescendo-lab-lifecycle.yml
  - type: Conformance
    url: conformance/crescendo-lab-conformance.yml
  - type: DataModel
    url: data-model/crescendo-lab-data-model.yml
  - type: Sandbox
    url: sandbox/crescendo-lab-sandbox.yml
  - type: Documentation
    url: https://sms.cresclab.com/developers.html#api
  - type: APIReference
    url: https://sms.cresclab.com/openapi.yaml
  - type: GettingStarted
    url: https://sms.cresclab.com/developers.html
- aid: crescendo-lab:crescendo-lab-sms-api
  name: Crescendo Lab SMS API
  description: Transactional (1-to-1) SMS send + status.
  humanURL: https://sms.cresclab.com/developers.html
  baseURL: https://sms.cresclab.com/api
  tags:
  - SMS
  properties:
  - type: OpenAPI
    url: openapi/crescendo-lab-sms-api-openapi.yml
  - type: Webhooks
    url: asyncapi/crescendo-lab-maacgo-webhooks.yml
  - type: ErrorCatalog
    url: errors/crescendo-lab-problem-types.yml
  - type: Lifecycle
    url: lifecycle/crescendo-lab-lifecycle.yml
  - type: Conformance
    url: conformance/crescendo-lab-conformance.yml
  - type: DataModel
    url: data-model/crescendo-lab-data-model.yml
  - type: Sandbox
    url: sandbox/crescendo-lab-sandbox.yml
  - type: Documentation
    url: https://sms.cresclab.com/developers.html#api
  - type: APIReference
    url: https://sms.cresclab.com/openapi.yaml
  - type: GettingStarted
    url: https://sms.cresclab.com/developers.html
- aid: crescendo-lab:crescendo-lab-teams-api
  name: Crescendo Lab Teams API
  description: Cost-attribution teams. Tag sends with a team to see which team sent/spent how much (shared wallet — reporting
    only, not a wallet split).
  humanURL: https://sms.cresclab.com/developers.html
  baseURL: https://sms.cresclab.com/api
  tags:
  - Team
  tags_raw:
  - Teams
  properties:
  - type: OpenAPI
    url: openapi/crescendo-lab-teams-api-openapi.yml
  - type: Webhooks
    url: asyncapi/crescendo-lab-maacgo-webhooks.yml
  - type: ErrorCatalog
    url: errors/crescendo-lab-problem-types.yml
  - type: Lifecycle
    url: lifecycle/crescendo-lab-lifecycle.yml
  - type: Conformance
    url: conformance/crescendo-lab-conformance.yml
  - type: DataModel
    url: data-model/crescendo-lab-data-model.yml
  - type: Sandbox
    url: sandbox/crescendo-lab-sandbox.yml
  - type: Documentation
    url: https://sms.cresclab.com/developers.html#api
  - type: APIReference
    url: https://sms.cresclab.com/openapi.yaml
  - type: GettingStarted
    url: https://sms.cresclab.com/developers.html
- aid: crescendo-lab:crescendo-lab-maac-go-api-api
  name: Crescendo Lab MAAC Go API
  description: The MAAC Go API API from Crescendo Lab — 0 operation(s) for maac go api.
  humanURL: https://sms.cresclab.com/developers.html
  baseURL: https://sms.cresclab.com/api
  tags:
  - MAAC Go API
  properties:
  - type: OpenAPI
    url: openapi/crescendo-lab-maac-go-api-api-openapi.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: CapabilityMap
  url: capabilities/crescendo-lab-capability-edges.yml
  name: Crescendo Lab Business Capability Map
- url: https://blog.cresclab.com/zh-tw/rss.xml
  type: BlogRSS
- type: Overlay
  url: overlays/crescendo-lab-maacgo-overlay.yaml
- type: Website
  url: https://cresclab.com
- type: DeveloperPortal
  url: https://sms.cresclab.com/developers.html
- type: Documentation
  url: https://sms.cresclab.com/developers.html#api
- type: Blog
  url: https://blog.cresclab.com/zh-tw
- type: HelpCenter
  url: https://crescendolab.zendesk.com/hc/zh-tw
- type: Pricing
  url: https://cresclab.com/pricing
- type: SignUp
  url: https://sms.cresclab.com/signup.html
- type: Login
  url: https://sms.cresclab.com/app.html
- type: TermsOfService
  url: https://sms.cresclab.com/terms.html
- type: PrivacyPolicy
  url: https://sms.cresclab.com/privacy.html
- type: GitHubOrganization
  url: https://github.com/Crescendo-Lab
- type: LLMsTxt
  url: llms/crescendo-lab-llms.txt
- type: SDKs
  url: packages/crescendo-lab-packages.yml
- type: Packages
  url: packages/crescendo-lab-packages.yml
- type: CLI
  url: cli/crescendo-lab-cli.yml
- type: MCPServer
  url: mcp/crescendo-lab-mcp.yml
- type: ToolCrosswalk
  url: mcp/crescendo-lab-tool-crosswalk.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Plans
  url: plans/crescendo-lab-plans-pricing.yml
- type: RateLimits
  url: rate-limits/crescendo-lab-rate-limits.yml
- type: APIReference
  url: https://sms.cresclab.com/openapi.yaml
- type: GettingStarted
  url: https://sms.cresclab.com/developers.html
- type: Sandbox
  url: sandbox/crescendo-lab-sandbox.yml
- type: Authentication
  url: authentication/crescendo-lab-authentication.yml
- type: Conventions
  url: conventions/crescendo-lab-conventions.yml
- type: Idempotency
  url: conventions/crescendo-lab-conventions.yml
- type: DomainSecurity
  url: security/crescendo-lab-domain-security.yml
x-enrichment:
  date: '2026-08-13'
  status: enriched
  artifacts_added: 5
  pass: local-v1
  note: WellKnown pointer removed 2026-08-13 — well-known/crescendo-lab-well-known.yml records 18 probes across both hosts
    and every one returned 404, so the artifact documents an absence and must not assert a served surface.

Crescendo Lab API — frequently asked questions

Does Crescendo Lab have an API?

Yes. APIs.io lists 5 APIs from Crescendo Lab, including Crescendo Lab Broadcast API, Crescendo Lab Contacts API and Crescendo Lab SMS API, and 2 more.

Is there an OpenAPI specification for the Crescendo Lab API?

Yes. APIs.io indexes 5 OpenAPI specifications for Crescendo Lab, each linked for download from this page.

How do I authenticate with the Crescendo Lab API?

Crescendo Lab uses bearer-token authentication (http · 1 scheme). The details are profiled on APIs.io as Crescendo Lab Authentication.

How much does the Crescendo Lab API cost?

APIs.io lists 8 pricing plans for Crescendo Lab, with each plan's price, limits and inclusions under Pricing Plans on this page.

Does Crescendo Lab have an MCP server?

Yes. APIs.io lists 1 MCP server for Crescendo Lab: Official hosted + local MCP server for MAAC Go (Crescendo Lab's self-serve Taiwan SMS platform). Lets Claude / Cursor / Windsurf / Codex send SMS, run broadcasts, pull logs, and check wallet balance o

Is the Crescendo Lab API ready for AI agents?

Crescendo Lab has a Kin Score of 57.2 out of 100 (strong) and an Agent Readiness score of 41.5 (agent-native), scored by API Evangelist on 2026-10-31.

Work with this as data

Every provider here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

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