The Hangar Addons MCP server lets an AI assistant work with the public side of the site: it can search the addon catalog, read news and help articles, and look up flight plans, scenery routes and virtual airlines. Everyone can use it and no token is needed, so this is the part to connect. A few extra tools for the Hangar Addons team (diagnostics and site operations) sit behind staff tokens. They are not available to creators or the public, and you can ignore them.
It speaks the Model Context Protocol over Streamable HTTP, in stateless mode, so every request stands alone and any server behind the load balancer can answer it.
Connect
The endpoint is:
https://hangaraddons.com/api/mcp
Claude Code
Without a token (public tools only):
claude mcp add --transport http hangar-addons https://hangaraddons.com/api/mcp
With a token:
claude mcp add --transport http hangar-addons https://hangaraddons.com/api/mcp --header "Authorization: Bearer hmcp_your_token_here"
Any other client
Point the client at the endpoint with the Streamable HTTP transport. If it has a place for headers, add Authorization: Bearer hmcp_your_token_here. A configuration file usually looks like this:
{
"mcpServers": {
"hangar-addons": {
"type": "http",
"url": "https://hangaraddons.com/api/mcp",
"headers": { "Authorization": "Bearer hmcp_your_token_here" }
}
}
}
Access
| Caller | What it can do | Calls per minute |
|---|---|---|
| No token | The public tools, resources and prompts below | 40 |
Token with Read | The same, with a higher limit | 600 |
Staff token with Diagnostics | Read what is slow or failing, site health, search index status | 600 |
Staff token with Operations | Change things: clear caches, reindex search, set the status of a diagnostic | 600 |
Tokens are issued by the Hangar Addons team and start with hmcp_. You do not need one for the public tools. A token is shown once when it is made and only a hash is kept, so a lost token is replaced, not recovered. A token can expire, and a revoked token stops working within a minute.
Every action that changes something is written to the site's audit log (area MCP) with the name of the token that did it, and get_mcp_activity lists them.
Nothing the public tools return is personal: no email addresses, no IP addresses, no member lists, no messages. Names that appear are the public credits on addons and plans, such as the creator of an addon.
Tools
Catalog
| Tool | What it does |
|---|---|
search_addons | Search addons by words, simulator, category, tag, airline, rating, age and sort order |
get_addon | One addon in full: description, install steps, files with checksums, images, videos, changelog and specs |
list_simulators | The simulators covered, with the slug to filter by |
list_categories | Categories with addon counts and the specs each describes |
get_catalog_stats | Totals for addons, downloads and data transferred |
list_collections, get_collection | Curated collections of addons |
list_aircraft_pages, get_addons_for_aircraft | Aircraft the site has pages for, and the addons and liveries for each |
Content and community
| Tool | What it does |
|---|---|
list_news, get_news_article | News articles |
list_help_articles, get_help_article, list_help_categories | The help center |
get_changelog | The website's changelog |
list_resources | Curated outside links |
get_recent_activity | Community totals, newest addons, downloads over time (no member names) |
search_scenery_routes, get_scenery_route | Scenery routes and their stops |
Flights
| Tool | What it does |
|---|---|
search_flight_plans, get_flight_plan | Shared flight plans by airports, aircraft, distance and words |
list_virtual_airlines, get_virtual_airline | Virtual airlines and their public pages |
Diagnostics (Hangar Addons staff only)
| Tool | What it does |
|---|---|
get_diagnostics_summary | Counts per kind: errors, slow queries, slow requests, slow pages, browser errors |
list_diagnostic_issues | The problems of one kind, grouped, with counts, timings and trend |
get_diagnostic_issue | One problem with its SQL or stack trace, route and trace id |
export_diagnostics | Everything in one Markdown or JSON report |
get_site_health | Health checks, uptime and memory of the API that answered |
get_maintenance_status | Whether maintenance mode is on |
get_search_index_status | Database and search index counts, to spot a gap |
get_mcp_activity | The latest actions made through this server |
Operations (Hangar Addons staff only)
| Tool | What it does |
|---|---|
clear_caches | Clears the page cache, the API cache, or both |
reindex_search | Queues every record to be indexed again (needs confirm: true) |
set_diagnostic_status | Marks a problem Resolved, Ignored or Open, with a note |
Tools carry the standard annotations: read only tools are marked read only and idempotent, and none of the operations are destructive. Tools that need a scope the caller does not have are not listed for that caller, and calling one anyway returns a message that says which scope is missing.
Resources
| URI | What it is |
|---|---|
hangar://about | What the site and this server are, and how to use them |
hangar://docs/mcp | This document |
hangar://catalog/simulators | The simulators, as JSON |
hangar://catalog/categories | The categories, as JSON |
hangar://addon/{slug} | An addon page as Markdown |
hangar://addon/{slug}/cover | The cover image of an addon, as an image |
hangar://help/{slug} | A help article as Markdown |
hangar://news/{slug} | A news article as Markdown |
hangar://diagnostics/report | The diagnostics report as Markdown (needs Diagnostics) |
Prompts
| Prompt | What it asks the assistant to do |
|---|---|
triage_diagnostics | Review what is slow or failing, group it, and suggest what to fix first |
investigate_slow_endpoint | Find why one endpoint is slow, using the timings, queries and trace ids |
draft_news_post | Write a news post from the changelog and recent news, in the site's voice |
review_addon_listing | Review an addon's page and suggest a better description and tags |
plan_scenery_flight | Suggest scenery addons and flight plans for a simulator and region |
Limits and behavior
- Page sizes are capped (25 or 30 items). Use
pageto read on. - The public tools never count as a view of a page, and never return items that are unpublished, hidden by their owner, or private.
- Results are cached on the server for a short time in places, so an addon changed a moment ago may take up to a minute to show.
- Without a token the limit is per address. A
429response carries aRetry-Afterheader. - A bad, revoked or expired token returns
401. Leave the header off to use the public tools.
Security notes for operators
- Give each client its own token, with the fewest scopes it needs, and an expiry.
- The
Operationsscope can clear caches and start a reindex. It cannot delete content, change users, change settings or turn maintenance mode on.