Steam MCP

A read-only Model Context Protocol server for the public Steam Web API and storefront — 37 tools, 5 prompts, and 2 resources that let any MCP client (Claude Desktop, Claude Code, Cursor, …) answer questions about Steam: your friends, games, playtime, and achievements, plus account-independent things like sales, reviews, live player counts, Steam Deck compatibility, discovery, recommendations, and co-op planning.

Read-only · official Steam APIs only · bring your own key · open source. Nobody logs in; the only credential is the free Steam Web API key you set yourself, and the server never writes, trades, posts, launches games, or makes purchases.

Quick start

Install uv, get a free Steam Web API key, then:

Claude Code

claude mcp add steam --env STEAM_API_KEY=YOUR_KEY -- uvx steam-mcp

Tip: this defaults to the current project. Add --scope user only if you want Steam in every project — that keeps its tools in context everywhere, so prefer per-project scope unless Steam is cross-cutting for you.

Claude Desktop — download steam-mcp.mcpb from the latest release, open it (Settings → Extensions), and paste your key.

Cursor / Cline / Windsurf and the manual pip setup are under Setup below.

What it can answer

Account / profile (needs a public profile; set STEAM_USER and "my"/"I" default to you — no SteamID needed):

• "Who's on my friends list, and who's online right now?"

• "Which of my friends own Helldivers 2 — and who's playing it now?"

• "It's game night — what co-op games do my online friends and I all own?"

• "Analyze my library — my backlog, and what I loved but abandoned."

• "Which achievements am I missing in Hollow Knight, and which are my rarest?"

• "What's on my wishlist, and is any of it on sale?"

• "Based on what I play most, what should I check out next?"

• "What's in my CS2 inventory, and which items are marketable?"

Account-independent (works for any game, no SteamID needed):

• "Is Baldur's Gate 3 worth buying — and how are its recent reviews trending?"

• "What's on sale right now, and what are the current top sellers?"

• "How many people are playing Counter-Strike 2 this minute?"

• "Will Hades II run on my Steam Deck?"

• "What's the Community Market price of a Field-Tested AK-47 | Redline?"

• "Is Elden Ring a soulslike? What are its community tags?"

• "Find well-reviewed co-op roguelikes under $20."

• "Recommend games like Hollow Knight that I don't already own."

Tools

Every tool supports response_format: "markdown" (default) or "json", and all are annotated readOnlyHint: true. Prefer the composite tools (steam_should_i_buy, steam_recommend, steam_discover, steam_plan_coop_night) over chaining several calls, and ask for json only when you need to parse fields. Tools that read localized text accept a language parameter — a Steam language name like french or schinese (default english).

* steam_discover, steam_should_i_buy, and steam_recommend need no key for the store data; their personalization (passing a steamid to use a user's library/taste) requires a key and a public profile.

Prompts & resources

Beyond tools, the server ships prompts (guided one-click flows that orchestrate the tools) and resources (reference Steam entities by URI):

• Prompts: what_should_i_play, is_it_worth_buying, plan_game_night, steam_deals, game_overview.

• Resources: steam://app/{appid} (store details) and steam://user/{steamid} (profile + live status).

Recent reviews: Steam's API only exposes a lifetime review summary — there is no "last 30 days" field. So steam_get_app_reviews with review_filter='recent' computes that score itself by paginating the newest reviews within day_range days (default 30). For games with a very high volume of recent reviews it counts up to ~600 and marks the result sampled: true.

Market prices: steam_get_market_price uses Steam's Community Market endpoints, which are undocumented and tightly rate-limited. Results are cached briefly; an item with no current listings reports its price as unavailable.

Setup

1. Get a free Steam Web API key

Visit https://steamcommunity.com/dev/apikey, sign in, register a domain (any domain you control works; localhost is commonly used for personal keys), and copy the key. Usage is governed by the Steam Web API Terms of Use.

2. Install

The published package needs no checkout (Python 3.10+):

uvx steam-mcp          # zero-install via uv (recommended)
# or
pip install steam-mcp  # run as: python -m steam_mcp.server

3. Add it to your MCP client

The server reads your key from the STEAM_API_KEY environment variable. Optionally, set STEAM_USER to your own Steam name (vanity name, SteamID64, or profile URL) so the "about me" tools — your library, wishlist, achievements, friends — default to you whenever you don't name a user. It's a public profile name, not a secret, and you can still pass a steamid to any call to override it.

Claude Code

claude mcp add steam --env STEAM_API_KEY=YOUR_KEY --env STEAM_USER=your_steam_name -- uvx steam-mcp

STEAM_USER is optional — drop the second --env if you'd rather give a SteamID to each call.

Claude Desktop — install steam-mcp.mcpb from the latest release via Settings → Extensions and paste your key (and, optionally, your Steam name).

Everything else (Claude Desktop config, Cursor, Cline, Windsurf, VS Code, …) — drop this block into the client's MCP config file:

{
  "mcpServers": {
    "steam": {
      "command": "uvx",
      "args": ["steam-mcp"],
      "env": {
        "STEAM_API_KEY": "YOUR_KEY_HERE",
        "STEAM_USER": "your_steam_name"
      }
    }
  }
}

Config locations: Claude Desktop claude_desktop_config.json (%APPDATA%\Claude\ on Windows, ~/Library/Application Support/Claude/ on macOS); Cursor .cursor/mcp.json; Cline cline_mcp_settings.json. Restart the client and the Steam tools appear. Running from a source checkout instead? Use "command": "python", "args": ["-m", "steam_mcp.server"].

Security

Read-only, official-Steam-only, and bring-your-own-key. In short:

• Read-only — never writes, trades, posts, launches games, or buys anything.

• Your key stays yours — read from STEAM_API_KEY; never written to disk, logged, cached, or put in output (and redacted from error messages).

• Official hosts only — the request layer refuses any host that isn't api.steampowered.com / store.steampowered.com / steamcommunity.com (SSRF guard), with per-host rate limiting and retry/backoff.

• Typed, validated inputs (extra="forbid"); no data kept between requests beyond a small TTL cache of non-user store data.

Full details and how to report issues are in SECURITY.md.

Versioning & stability

steam-mcp follows Semantic Versioning. As of 1.0, the following are the stable public surface — they won't change without a major (2.0) release:

• Tool names and their input parameters (names, types, whether required, defaults)

• JSON output fields (response_format: "json") — names, types, and structure

• Prompt names/arguments and resource URI templates (steam://app/{appid}, steam://user/{steamid})

• Core semantics: read-only, bring-your-own-key, prices in cents / playtime in minutes, and errors returned as strings

Within a major version, minor releases may add tools, prompts, resources, optional parameters, and JSON fields; patch releases are bug fixes only. The Markdown output wording, internal implementation, caching behavior, and which Steam endpoints back a given tool may change at any time and are not part of the contract.

License

MIT. Not affiliated with Valve. "Steam" is a trademark of Valve Corporation.