Steam MCP Server

Overview Schema Source Related Servers Discussions Admin

Get a game's full achievement list

get_game_achievements

Read-only

Retrieve a game's achievement list by appid, including names, descriptions, hidden flags, and global unlock percentages. Returns up to 150 achievements; empty list indicates no schema.

Instructions

List a game's achievements by appid with their names, descriptions, hidden flag and global unlock % (rarity), in the game's own definition order (capped at the first 150; check returned vs total — most games have far fewer). An empty achievements list with total:0 means this appid has no achievement schema at all — a DLC, soundtrack, tool or demo, or an appid that doesn't exist; the two are not reported separately here, so use get_game to confirm the appid is a real base game. Requires STEAM_API_KEY (the achievement schema needs a key). For just the rarity by internal id without a key, use get_global_achievements; for a few named highlights, see get_game's achievements_highlighted; for a specific player's own unlock progress instead of the catalog-wide list, use get_player_achievements. Get the appid from search_games.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`appid`	Yes	Steam application id (appid). Get it from search_games.
`language`	No	Language for achievement names/descriptions; overrides STEAM_LANGUAGE. Use Steam's own language NAME — english, russian, schinese/tchinese — not an ISO code like en/ru/zh. An unrecognized value is never an error: text comes back in English and any `tags` list comes back EMPTY, which reads as 'this game has no tags' rather than as a bad language. (Filtering BY tags is the one loud case — it fails outright.)

Output Schema

TableJSON Schema

Name	Required	Description
`game`	Yes	The game's name from Valve's achievement schema — occasionally an internal dev codename rather than the store title (e.g. 'Fiber' for Persona 5 Royal). Treat the appid you passed as the reliable identifier, or get the store title from get_game.
`total`	Yes
`returned`	Yes
`achievements`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed9 schema fields changedv0.14.0Sep 27, 2026

changedInput schema / properties / language / description

Previous value: -"Language for achievement names/descriptions; overrides STEAM_LANGUAGE."New value: +"Language for achievement names/descriptions; overrides STEAM_LANGUAGE. Use Steam's own language NAME — english, russian, schinese/tchinese — not an ISO code like en/ru/zh. An unrecognized value is never an error: text comes back in English and any `tags` list comes back EMPTY, which reads as 'this game has no tags' rather than as a bad language. (Filtering BY tags is the one loud case — it fails outright.)"

removedOutput schema / properties / achievements / items / properties / description / anyOf
```
Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]
```
addedOutput schema / properties / achievements / items / properties / description / type
```
Added value: +[
+  "string",
+  "null"
+]
```
removedOutput schema / properties / achievements / items / properties / global_unlock_pct / anyOf
```
Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]
```
addedOutput schema / properties / achievements / items / properties / global_unlock_pct / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / achievements / items / properties / name / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / achievements / items / properties / name / type
```
Added value: +[
+  "string",
+  "null"
+]
```

removedOutput schema / properties / game / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / game / type
```
Added value: +[
+  "string",
+  "null"
+]
```

Changed1 schema field changedv0.13.1Aug 17, 2026

addedOutput schema / properties / game / description

Added value: +"The game's name from Valve's achievement schema — occasionally an internal dev codename rather than the store title (e.g. 'Fiber' for Persona 5 Royal). Treat the appid you passed as the reliable identifier, or get the store title from get_game."

Changed1 schema field changedv0.12.1Jul 30, 2026
- addedInput schema / additionalProperties
```
Added value: +false
```

Changed2 schema fields changedv0.10.4Jul 26, 2026

addedOutput schema / properties / returned
```
Added value: +{
+  "type": "number"
+}
```

changedOutput schema / required

Previous value: -[
-  "game",
-  "total",
-  "achievements"
-]New value: +[
+  "game",
+  "total",
+  "returned",
+  "achievements"
+]

Addedv0.10.2Jul 22, 2026
Removedv0.8.0Jul 17, 2026
First observedv0.1.0Jun 29, 2026

TDQS

A4.6/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds valuable behavioral context beyond annotations: the 150-item cap, the need to compare `returned` vs `total`, the ambiguous empty-list meaning, the key requirement, and the language fallback behavior. It does not contradict annotations. A 4 is appropriate because it adds rich context without being exhaustive about every edge case.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is dense but well-organized: the core behavior is front-loaded, followed by the cap/empty-list caveat, the key requirement, and sibling routing. Every sentence earns its place, though the sibling list is long and could arguably be trimmed. It is appropriately sized for a tool with this many caveats.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the output schema exists, the description doesn't need to explain return values. It covers the key requirement, the cap, the ambiguous empty-list case, the language fallback, and how to get the appid. For a read-only list tool with two parameters and a rich output schema, nothing an agent needs to call it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The description adds meaning beyond the schema by explaining the cap, the empty-list semantics, and the language fallback behavior (unrecognized language returns English and empty tags). It also clarifies that the appid must be a real base game. This pushes it above the baseline.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb and resource ('List a game's achievements by appid') and enumerates exactly what is returned (names, descriptions, hidden flag, global unlock %, order, cap). It also distinguishes itself from siblings by naming get_global_achievements, get_game, and get_player_achievements, so an agent can tell them apart without opening schemas.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives explicit when-to-use guidance: it requires STEAM_API_KEY, tells the agent to use get_global_achievements when only rarity by internal id is needed without a key, get_game for confirming a real base game, get_player_achievements for a specific player's progress, and search_games to obtain the appid. It also explains the empty-list/total:0 case and how to disambiguate it, which is exactly the kind of routing an agent needs.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.