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Synthflow

Synthflow is an enterprise-ready no-code Voice AI platform for automating phone conversations at scale. The product combines a visual agent designer with in-house telephony, sub-100ms latency, and a 99.99% uptime guarantee, so businesses can build, deploy, and operate voice agents without third-party carriers. Synthflow exposes a REST Platform API for assistants, calls, phone numbers, knowledge bases, and custom actions, with bearer token authentication. The platform claims more than 200 integrations including HubSpot, Salesforce, Cal.com, Zapier, and CCaaS systems, plus custom webhook actions. Compliance covers SOC 2, HIPAA, PCI DSS, and GDPR with end-to-end encryption and audit logging.

agent ready

Limited machine-readable signal and partial portal coverage — documentation a human can read, but little a machine or agent can consume without scraping.

Kin Score

API Evangelist profiles Synthflow the way a machine reads it — 15 machine-readable artifacts across 8 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.

Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Synthflow scores 41.8/100 (thin), with a separate agent-readiness read of 48/100 (agent ready). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.

Kin Score

This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 41.8/100 · thin
Contract Quality 12.6 / 25
Developer Ergonomics 4.3 / 20
Commercial Clarity 12.1 / 20
Operational Transparency 2.7 / 13
Governance 0.0 / 12
Discoverability 10.0 / 10
Agent readiness — 48/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 15 / 15
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 0 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3

How we profile Synthflow

Each block below is one kind of artifact we hold for Synthflow. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.

APIs 8

Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.

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

Synthflow Platform API

The Synthflow Platform API provides REST endpoints to manage assistants, phone numbers, calls, knowledge bases, and custom actions for no-code voice AI agents. Authentication is...

Synthflow Default API

The Default API from Synthflow — 49 operation(s) for default.

Synthflow subpackage_chat API

The subpackage_chat API from Synthflow — 4 operation(s) for subpackage_chat.

Synthflow subpackage_contacts API

The subpackage_contacts API from Synthflow — 2 operation(s) for subpackage_contacts.

Synthflow subpackage_mcp API

The subpackage_mcp API from Synthflow — 3 operation(s) for subpackage_mcp.

Synthflow subpackage_memoryStores API

The subpackage_memoryStores API from Synthflow — 1 operation(s) for subpackage_memorystores.

Synthflow subpackage_phoneNumbers API

The subpackage_phoneNumbers API from Synthflow — 3 operation(s) for subpackage_phonenumbers.

Synthflow subpackage_webhookLogs API

The subpackage_webhookLogs API from Synthflow — 2 operation(s) for subpackage_webhooklogs.

Scroll within the panel for all 8 ·

Open Collections 1

Open, tool-agnostic collections carry the same runnable value as Postman without locking you to one client — the portable, forkable form of the same exercise.

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

Platform API

OPEN COLLECTION

Pricing Plans 1

Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the six things the Kin Score reads for commercial clarity.

Published pricing tiers and plan structures.

Rate Limits 1

Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.

Documented rate limits and quota policies.

Synthflow Rate Limits

2 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals let a buyer model the financial operations of an API before it's live. We profile them for the same reason we profile pricing: the money is part of the contract.

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

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.

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

Synthflow Authentication

http · 1 scheme

SECURITY

Synthflow Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Agentic Access 1

An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.

Recommended x-agentic-access execution contracts for AI agents.

Synthflow Agentic Access

98 operations · 61 acting

98 operations · 61 acting

AGENTIC

Resources

Every other property we hold for Synthflow — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.

Documentation 1

Reference material describing how the API behaves

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

Access & Security 2

Authentication, authorization, and security posture

Commercial 3

Pricing, plans, and the legal terms of use

Company 3

The organization behind the API

Other 1

Properties that don't map to a standard resource type

← All providers · Data indexed from github.com/api-evangelist/synthflow · machine-readable index on apis.io