# Overview

The SPACE GASS API provides programmatic access to SPACE GASS structural
analysis data. Use it to open job files, read and edit structural
entities, run analyses, and query results.

The API is a **headless service** — it runs as a local server on your
machine without any program UI. There is no interaction with the
SPACE GASS desktop interface. All operations are performed through
HTTP requests to the local server.

## What You Can Do

- **Open and manage job files** — Create, open, save, and close
  SPACE GASS `.sg` project files
- **Read, write, and edit structural data** — Nodes, members, sections,
  materials, load cases, load categories, and load case groups. Create
  or update many entities at once using bulk operations.
- **Run analyses** — Start linear, non-linear, buckling, and dynamic
  frequency analyses, and monitor progress in real time
- **Query analysis results** — Retrieve node displacements, reactions,
  member forces, buckling load factors, and more

## Prerequisites

To get access to the API, follow the steps in the
[Quick Start](/quick-start). You will need:

- [SPACE GASS](https://www.spacegass.com/) **14.5 or later** installed on your machine
- SPACE GASS has been opened at least once to initialize the required
  data files

## Licensing

API access is included with Pro and above subscriptions, or available
as a yearly add-on for perpetual license holders. See
[Licensing](/licensing) for details or visit
[spacegass.com](https://www.spacegass.com/) for pricing.

## Authentication

No authentication is required. The API runs locally and is accessed
over plain HTTP. See [Authentication](/authentication) for
details.

## SDK Clients

Generated SDK clients are available for:

- **C#** — `SpaceGassApi` (NuGet package)
- **Python** — `space-gass-api` (pip installable)

Both are generated from the OpenAPI specification using
[Microsoft Kiota](https://learn.microsoft.com/en-us/openapi/kiota/overview).
The machine-readable spec is published at
[`api/1/schema.json`](https://api.spacegass.com/docs/api/1/schema.json)
if you want to generate a client for another language or feed it to an LLM.

## Using with AI coding agents

Building scripts with an AI assistant (Claude Code, Cursor, Copilot, ChatGPT)?
Point it at these single, clean, machine-readable entry points instead of
letting it crawl the source repo:

- **Full docs bundle for LLMs:** [`llms-full.txt`](https://api.spacegass.com/docs/llms-full.txt)
- **OpenAPI spec (JSON):** [`api/1/schema.json`](https://api.spacegass.com/docs/api/1/schema.json)
- **Repo as an MCP server** (search docs, examples, and code with zero setup):
  [`gitmcp.io/SpaceGass/space-gass-api`](https://gitmcp.io/SpaceGass/space-gass-api)

Or paste this primer straight into your AI assistant to point it at everything
in one step:

```text
You have access to the SPACE GASS structural-analysis API — a LOCAL, no-auth
service at http://localhost:34560 (base path /api/v1). Load these first:
- Full docs bundle:  https://api.spacegass.com/docs/llms-full.txt
- OpenAPI spec:      https://api.spacegass.com/docs/api/1/schema.json
- Repo via GitMCP:   https://gitmcp.io/SpaceGass/space-gass-api

SDKs (Kiota, fluent builder chains, async):
- Python:  pip install space-gass-api    ->  from space_gass_api import SpaceGassApiClient
- C#:      dotnet add package SpaceGassApi
Both expose SpaceGassApiClient.CreateClient() (no auth, base URL auto-set).
Use raw.githubusercontent.com for repo files, never /blob/ URLs.
```

## Next Steps

- [Quick Start](/quick-start) — Get up and running
  in 5 minutes
- [Simple Beam Model](/examples/simple-beam) — Full walkthrough
  building a model, running analysis, and querying results
- [API Reference](/api) — Browse all endpoints interactively