---
title: "MCP Multi-Chart Context"
method: POST
path: "/mcp/multi-chart-context"
tags: ["AI & MCP"]
---

# MCP Multi-Chart Context

`POST /mcp/multi-chart-context`

Compact context for MCP agents working across multiple charts.

## Request body

- MultiChart — Group of 2-10 natal charts for collective calculations: group synastry, penta-chart, etc.
  - `inputs` ChartInput[], required
    - `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

## Response `200`

Successful calculation

- object
  - `ok` boolean
  - `data` object
    - `summaries` unknown[], nullable
      - unknown

## 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 `inputs/items/latitude` became not nullable
  - the request property `inputs/items/longitude` became not nullable
  - the request property `inputs/items/latitude` became required
  - the request property `inputs/items/longitude` became required
  - …6 more

[Change history](https://skmtc.dev/astroway/apis/astroway-calculation-api/changes/mcp/multi-chart-context/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/821c8bafa295/schema)