Aggregate a Steam player's unlocked achievements against global unlock-rate percentages using the Steamworks Web API
domain: partner.steamgames.com · 5 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Call ISteamUserStats/GetSchemaForGame/v2 to get the full list of achievement and stat definitions for the app.
Call ISteamUserStats/GetPlayerAchievements/v1 with an authenticated Web API key, steamid, and appid to fetch which achievements the player has unlocked and their timestamps.
Call ISteamUserStats/GetUserStatsForGame/v2 to pull the player's raw numeric stats for the same app.
Call ISteamUserStats/GetGlobalAchievementPercentagesForApp/v2 (no key required) to get the global unlock percentage for each achievement.
Join the per-player unlock list against the global percentage list on the achievement API name to compute rarity-weighted completion scores.
Known gotchas
GetPlayerAchievements requires the target Steam profile's game details to be set to public, or the call returns a privacy error even with a valid key.
Achievement API names are case-sensitive and must match exactly between GetSchemaForGame and GetPlayerAchievements/GetGlobalAchievementPercentagesForApp.
GetGlobalAchievementPercentagesForApp figures update on a delay and lag behind real-time unlocks, so don't treat them as live data.
Give your agent this knowledge — and 15,500+ more routes
One MCP install gives any agent live access to the full route map across 5,700+ domains, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp
Need this verified for your stack — or a route we don't have yet?