Reply drafting

A customer thread plus your context → a ready-to-send reply in the right tone, with an internal note for the agent.

POST /v1/reply$0.05/reply · 5 credits, charged only on success

Send this

{
  "thread": "Customer: I was charged twice for order 5561 and support hasn't replied in 3 days.",
  "context": "Duplicate charge confirmed in Stripe; refund takes 5-10 days.",
  "tone": "apologetic",
  "goal": "Refund the duplicate, keep the customer",
  "senderName": "Sam"
}

Every response carries usage — the credits burned and your remaining balance. A failed call never burns credits.

Try it live against your own key in the interactive reference; every account gets 500 free credits a month, no card.

Get this back

{
  "reply": "Hi — you're right, and I'm sorry about the silence. I've refunded the duplicate charge just now…",
  "subject": "Re: Double charge on order 5561 — refunded",
  "internalNote": "Refund issued; check why the retry fired twice on this order.",
  "usage": {
    "credits": 5,
    "balanceRemaining": 318
  }
}

Four ways in. Same $0.05/reply.

curl

curl https://api.kynth.studio/v1/reply \
  -H "Authorization: Bearer ksk_live_…" \
  -H "Content-Type: application/json" \
  -d '{"thread":"Customer: I was charged twice for order 5561 and support hasn't replied in 3 days.","context":"Duplicate charge confirmed in Stripe; refund takes 5-10 days.","tone":"apologetic","goal":"Refund the duplicate, keep the customer","senderName":"Sam"}'

TypeScript

import { KynthCore } from "@kynth/api";

const kynth = new KynthCore({ apiKey: process.env.KYNTH_API_KEY! });
const result = await kynth.reply({
  "thread": "Customer: I was charged twice for order 5561 and support hasn't replied in 3 days.",
  "context": "Duplicate charge confirmed in Stripe; refund takes 5-10 days.",
  "tone": "apologetic",
  "goal": "Refund the duplicate, keep the customer",
  "senderName": "Sam"
});

Python

from kynth import Kynth

client = Kynth(api_key=os.environ["KYNTH_API_KEY"])
result = client.reply(
    thread="Customer: I was charged twice for order 5561 and support hasn't replied in 3 days.",
    context="Duplicate charge confirmed in Stripe; refund takes 5-10 days.",
    tone="apologetic",
    goal="Refund the duplicate, keep the customer",
    senderName="Sam",
)

MCP

// One-time setup in your MCP client (Claude, Cursor, …):
{ "mcpServers": { "kynth-core": {
    "command": "npx", "args": ["@kynth/api-mcp"],
    "env": { "KYNTH_API_KEY": "ksk_live_…" } } } }

// Then the agent just calls the kynth_reply tool.

More from communication

Summarize

$0.03/call

A meeting transcript, thread, or report → a tight summary, key points, and extracted action items.

Sentiment

$0.02/call

Turn a review or support message into a sentiment score, per-aspect breakdown, and the themes driving it.

Ticket triage

$0.03/ticket

A support ticket → priority, category, the team it belongs to, sentiment, SLA risk, and a suggested first response.

Get your key — 500 free credits monthly