ArcadeIndex
io.arcadeindex/catalogarcadeindex.iostreamable-httpv1.6.0Scanned
Find free browser games re-checked playable within 8 days, by genre, mood, age rating and players.
7 tools: 5 change things and 2 only read.
- Reads private data · 0
- Reads text others write · 1
- Can send data out · 0
- 5 findings, 1 high
Anlyon alternative
5 of these tools change something. Run those as governed actions.
Declare what an action changes, and Anlyon puts it under a shared limit, binds every approval to the exact request, and grades the outcome. It works on any HTTPS API you can describe as an action.
Anlyon does not run, proxy or govern this MCP server. A tool your own code calls directly is not routed through Anlyon and is not governed by it.
Import an OpenAPI spec →Tools
Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.
7 tools
Changes things 5Claude Code: ask
games_likeGames similar to an anchor game, ordered by similarity, each with similarity_reasons.1 finding
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
The description names a tool "in" that this server does not list.
What this check looks forMatched text
description: "...whose args you can call again (with the tool named in tool, when set). Quote match_reasons an..."
Description, as the server wrote it Games similar to an anchor game, ordered by similarity, each with similarity_reasons. Returns only published, playable games verified within the last 8 days (listing-only games with include_listing_only=true; plays=here or plays=developer_site picks one kind). content_rating_max defaults to teen. Zero results is a success with code NO_MATCHES and up to 3 executed relaxations whose args you can call again (with the tool named in tool, when set). Quote match_reasons and link play_url; render 'via ArcadeIndex' per the attribution block.
Annotations the server declares
- title: Games like a game
- readOnlyHint: true
- destructiveHint: false
- openWorldHint: false
- idempotentHint: true
new_gamesGames published in the last 30 days, newest first.1 finding
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
The description names a tool "in" that this server does not list.
What this check looks forMatched text
description: "...whose args you can call again (with the tool named in tool, when set). Quote match_reasons an..."
Description, as the server wrote it Games published in the last 30 days, newest first. Returns only published, playable games verified within the last 8 days (listing-only games with include_listing_only=true; plays=here or plays=developer_site picks one kind). content_rating_max defaults to teen. Zero results is a success with code NO_MATCHES and up to 3 executed relaxations whose args you can call again (with the tool named in tool, when set). Quote match_reasons and link play_url; render 'via ArcadeIndex' per the attribution block.
Annotations the server declares
- title: New games
- readOnlyHint: true
- destructiveHint: false
- openWorldHint: false
- idempotentHint: true
play_gamePlay an ArcadeIndex game right inside the chat.1 finding
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- High
The description contains "do not tell the user", an instruction to keep something from the user.
What this check looks forMatched text
description: "...game on arcadeindex.io in a new tab, so do not tell the user the game is running in the chat unless..."
Description, as the server wrote it Play an ArcadeIndex game right inside the chat. Pass game_id (an id, {slug}-{id}, or a game's url from search_games, trending, games_like or new_games results) or query (the top search hit is played; a game that only plays on its developer's site comes back as link_out). Hosts that support MCP Apps show a player with Next game and More like this (mode player); some chat apps do not allow the game frame yet, and then the player offers the game on arcadeindex.io in a new tab, so do not tell the user the game is running in the chat unless they say so. Games that cannot be framed here (listing-only, not checked in the last 8 days, Mature, or a site the chat app does not allow) return mode link_out with link_out.url and the reason: give the user that link. Hosts without MCP Apps get the same data as text: link play_url. Errors: NOT_FOUND, INVALID_ARGUMENT.
Annotations the server declares
- title: Play a game in the chat
- readOnlyHint: true
- destructiveHint: false
- openWorldHint: false
- idempotentHint: true
random_gameOne random eligible game for 'surprise me' flows; pass seed for a deterministic pick.No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Description, as the server wrote it One random eligible game for 'surprise me' flows; pass seed for a deterministic pick. Never returns Mature games. Zero eligible games gives game: null with code NO_MATCHES and relaxations.
Annotations the server declares
- title: Random game
- readOnlyHint: true
- destructiveHint: false
- openWorldHint: false
- idempotentHint: false
trendingGames trending over the last day or week (genre scope when genre is set).1 finding
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
The description names a tool "in" that this server does not list.
What this check looks forMatched text
description: "...whose args you can call again (with the tool named in tool, when set). Quote match_reasons an..."
Description, as the server wrote it Games trending over the last day or week (genre scope when genre is set). trending_basis says whether play data or the recency fallback was used. Returns only published, playable games verified within the last 8 days (listing-only games with include_listing_only=true; plays=here or plays=developer_site picks one kind). content_rating_max defaults to teen. Zero results is a success with code NO_MATCHES and up to 3 executed relaxations whose args you can call again (with the tool named in tool, when set). Quote match_reasons and link play_url; render 'via ArcadeIndex' per the attribution block.
Annotations the server declares
- title: Trending games
- readOnlyHint: true
- destructiveHint: false
- openWorldHint: false
- idempotentHint: true
Only reads 2Show 2 read-only tools
get_gameFull details of one game by id or {slug}-{id}.No findings
Why it is in this group
- The name "get_game" says "get": a word for reading.
Description, as the server wrote it Full details of one game by id or {slug}-{id}. Aliased ids resolve to the canonical game (requested_id is set). Also returns listing-only, stale or suspect games: do NOT present play_url as instantly playable unless play_ready is true. Errors: NOT_FOUND (unknown, unavailable or not public), GONE (delisted).
Annotations the server declares
- title: Get game details
- readOnlyHint: true
- destructiveHint: false
- openWorldHint: false
- idempotentHint: true
search_gamesFind web games from a natural-language query plus optional filters (genre, mood, session length, players, quality, content rating, difficulty, inputs).Reads text others write1 finding
Why it is in this group
- The name "search_games" says "search": a word for reading.
What it can reach
- untrusted-inputThe description's first sentence says "find" and "web": it reads web pages, which anyone can write.
Findings
- Warn
The description names a tool "in" that this server does not list.
What this check looks forMatched text
description: "...whose args you can call again (with the tool named in tool, when set). Quote match_reasons an..."
Description, as the server wrote it Find web games from a natural-language query plus optional filters (genre, mood, session length, players, quality, content rating, difficulty, inputs). Phrases like 'for kids', '2 player', 'under 10 minutes', 'not a shooter', 'easy' or 'chill' are turned into filters (echoed as interpreted_filters); explicit params win. 'like {title}' or 'similar to {title}' naming a game in the catalog returns that game's games_like results (anchor is set). Returns only published, playable games verified within the last 8 days (listing-only games with include_listing_only=true; plays=here or plays=developer_site picks one kind). content_rating_max defaults to teen. Zero results is a success with code NO_MATCHES and up to 3 executed relaxations whose args you can call again (with the tool named in tool, when set). Quote match_reasons and link play_url; render 'via ArcadeIndex' per the attribution block.
Annotations the server declares
- title: Search games
- readOnlyHint: true
- destructiveHint: false
- openWorldHint: false
- idempotentHint: true
This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.
Exfil surface
Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.
No private-data, untrusted-input, outbound path in this server alone: no tool is tagged private-data or outbound.
- Reads private data0
- Reads files, mail, messages, databases, secrets, calendars or repositories.
- Reads text others write1
- Brings in text someone else can write: web pages, inbound email, messages, issues and comments.
- Can send data out0
- Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.
Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.
Findings
Matches of fixed checks, with the text they matched.
- Highplay_game
The description contains "do not tell the user", an instruction to keep something from the user.
What this check looks forMatched text
description: "...game on arcadeindex.io in a new tab, so do not tell the user the game is running in the chat unless..."
- Warnsearch_games
The description names a tool "in" that this server does not list.
What this check looks forMatched text
description: "...whose args you can call again (with the tool named in tool, when set). Quote match_reasons an..."
- Warntrending
The description names a tool "in" that this server does not list.
What this check looks forMatched text
description: "...whose args you can call again (with the tool named in tool, when set). Quote match_reasons an..."
- Warngames_like
The description names a tool "in" that this server does not list.
What this check looks forMatched text
description: "...whose args you can call again (with the tool named in tool, when set). Quote match_reasons an..."
- Warnnew_games
The description names a tool "in" that this server does not list.
What this check looks forMatched text
description: "...whose args you can call again (with the tool named in tool, when set). Quote match_reasons an..."
History
Changes to its tool definitions and to its remote endpoint, newest first.
No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.
Install
Pinned to version 1.6.0. Values in angle brackets are yours to fill in.
claude mcp add --transport http catalog https://arcadeindex.io/mcp/catalogclaude mcp add --transport http catalog https://arcadeindex.io/mcp/catalogRun in a terminal.
Claude Code permissions
Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.
{
"permissions": {
"allow": [
"mcp__catalog__search_games",
"mcp__catalog__get_game"
],
"ask": [
"mcp__catalog__trending",
"mcp__catalog__games_like",
"mcp__catalog__random_game",
"mcp__catalog__new_games",
"mcp__catalog__play_game"
],
"deny": []
}
}Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as catalog. Review it before you use it.
Capability tags behind 1 rule
- mcp__catalog__search_games untrusted-input
Pin
Keep the decision: fail CI when the tools change, follow every change, or show a badge.
Pin in CI
Fail a build when the tools you reviewed are not the tools the server serves today.
curl -s "https://anlyon.dev/api/v1/servers/io.arcadeindex/catalog/verify?hash=6a9ad589335bbcbd1937e8e7a23cea7dfba5ba87cdf6ff624bf25c980c2a21d5" | jq -e '.changed == false'Pinned hash 6a9ad589335b, from Oct 23, 2026, 22:17 UTC.
Watch
Get told when its tools change: a new tool, a new description, a new class.
https://anlyon.dev/servers/io.arcadeindex/catalog/changes.xmlAn Atom feed. Works in any feed reader or Slack's RSS app.
Badge
[](https://anlyon.dev/servers/io.arcadeindex/catalog)Source: MCP Registry. Synced Oct 23, 2026, 23:17 UTC.