Steam MCP

A read-only Model Context Protocol server for the public Steam Web API and storefront — 41 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 · open source. Nobody logs in, and the server never writes, trades, posts, launches games, or makes purchases.

Quick start — no API key needed

Install uv, then:

Claude Code

claude mcp add steam -- uvx steam-mcp

That's the whole setup. 19 of the 41 tools work with no credential at all — anything about the store or a game itself:

"Is Baldur's Gate 3 worth buying, and how are its recent reviews trending?" "What co-op games are on sale under £20 right now?" "How many people are playing Helldivers 2 this minute?" "Will Hades II run properly on my Steam Deck?"

The three game-finders (steam_discover, steam_should_i_buy, steam_recommend) work without a key too, as long as you don't personalize them.

Adding your own account

A free Steam Web API key (a minute to get) unlocks the other 22 — the ones that read a specific account: library, playtime, friends, achievements, wishlist, inventory. Add STEAM_USER too and "my"/"I" default to you, so you never have to paste a SteamID:

claude mcp add steam --env STEAM_API_KEY=YOUR_KEY --env STEAM_USER=your_steam_name -- 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 and open it (Settings → Extensions). Both fields are optional; leave them blank for the keyless tools and fill them in later.

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

Without a key, the account tools are still listed but marked [unavailable: needs STEAM_API_KEY], so your assistant knows to reach for a keyless tool instead of failing at one it can't use.

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.

† steam_get_inventory reads a keyless endpoint, but it still has to know whose inventory — and turning a vanity name (or STEAM_USER) into a SteamID64 is itself a keyed call. Pass a raw 17-digit SteamID64 and it works with no key.

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_get_app_reviews with review_filter='recent' asks Steam for the exact review count and score of the last day_range days (default 30), the same numbers as the store page's "Recent Reviews" row. If Steam refuses that request it falls back to counting the newest reviews, up to recent_max_reviews, and marks the result sampled: true.

Whose reviews count: by default both scores count what the store page counts: Steam purchases only for a paid game (key activations are left out) and everyone for a free game. purchase_type='all' or 'steam' forces either.

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 (optional)

Skip this if you only want the 19 keyless tools — the server runs fine without a key and the account tools simply advertise themselves as unavailable.

To unlock the account tools, 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

Both MCP Python SDK majors work (mcp>=1.28). On the v2 SDK the server speaks spec revision 2026-07-28 — stateless, no initialize handshake — advertises cache hints on its tool/prompt/resource listings, and can ask you which Steam account is yours when STEAM_USER isn't set (once per session, and only if your client supports elicitation). On the v1.x line it serves the initialize handshake that modern clients fall back to anyway. Nothing to configure either way.

TLS note: the HTTP client is httpx2, which verifies certificates against your operating system's trust store rather than a bundled CA list. If you run this somewhere minimal (a slim container with no system CA store, or behind a private CA), point SSL_CERT_FILE or SSL_CERT_DIR at a CA bundle.

3. Add it to your MCP client

Both settings are optional. STEAM_API_KEY unlocks the account tools; STEAM_USER (your Steam vanity name, SteamID64, or profile URL) makes those tools default to you whenever you don't name a user, so you never paste a SteamID. It's a public profile name, not a secret, and you can still pass a steamid to any call to override it.

Configure neither and you get the keyless server; configure both and you get everything.

Smaller tool set (optional). Every tool's definition goes into the model's context on every request, about 11.5k tokens for all 41. Set STEAM_MCP_TOOLS=essentials to load just 15: search, the one-call game brief, details, reviews, compare, should-I-buy, discover, recommend, update impact, sales, and your profile, library, library analysis, wishlist and co-op night. Add others by name (essentials,get_inventory), or list exactly the ones you want. The default is all. The built-in prompts may mention a tool your set leaves out.

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"
      }
    }
  }
}

Installing with an AI agent such as Cline? Point it at llms-install.md, which walks it through the setup.

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.