---
title: "MCP Streaming Chat"
method: POST
path: "/mcp/streaming"
tags: ["AI & MCP"]
---

# MCP Streaming Chat

`POST /mcp/streaming`

Server-Sent Events streaming chat completion with optional chart context.

## Request body

- Streaming
  - `message` string, required
  - `chart` ChartInput — Birth data for a single natal chart. Required: date (YYYY-MM-DD), time (HH:mm:ss), latitude and longitude in decimal degrees. The short forms lat, lon, lng and tz are rejected with 400 INVALID_FIELD; pass the full names. timezoneOffset is hours from UTC and defaults to 0, meaning UTC. city is a display label only: nothing here geocodes it, so it never stands in for coordinates.
    - `date` string, required
    - `time` string, required
    - `timezoneOffset` number, nullable
    - `latitude` number, required
    - `longitude` number, required
    - `houseSystem` string
    - `name` string
    - `city` string
    - `zodiacType` 'tropical' | 'sidereal'
    - `ayanamsaId` number, nullable
    - `cosmogram` boolean
  - `language` 'uk' | 'en' | 'de' | 'ru' | 'pl' | 'es' | 'pt' | 'hi' | 'fr' | 'ko' | 'it' | 'ja' | 'id' | 'tr' | 'nl' | 'ro' | 'cs' | 'vi' | 'ar' | 'el' | 'hu'

## Response `200`

Successful calculation

- object
  - `ok` boolean
  - `data` object

## Other responses

- `400` — Validation error
- `401` — Missing or invalid API key

## Changes

- **2026-08-11** `b0533bcc12c0` — 4 breaking, 4 warning, 2 info
  - the request property `chart/latitude` became not nullable
  - the request property `chart/longitude` became not nullable
  - the request property `chart/latitude` became required
  - the request property `chart/longitude` became required
  - …6 more

[Change history](https://skmtc.dev/astroway/apis/astroway-calculation-api/changes/mcp/streaming/post.md)

---

[API](https://skmtc.dev/astroway/apis/astroway-calculation-api.md) · [All operations](https://skmtc.dev/astroway/apis/astroway-calculation-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/astroway/astroway-calculation-api/revisions/b0533bcc12c0/schema)