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mps-language-analysis

mps-language-analysis is a skill for Claude Code, Codex from JetBrains/MPS. It costs 57 tokens per session (784 once invoked), scanned A, original, Apache-2.0.

An analysis guide for JetBrains MPS languages, which are custom languages built inside the MPS development environment. It maps their concepts, properties, relationships, editors, rules, behaviours, and metadata.

In plain words
What is it for?
Use it to inspect a language's structure, find concepts and examples, understand editor and constraint aspects, and obtain precise concept names for model blueprints.
Why use it?
It helps developers understand an unfamiliar MPS language before editing models or creating new language elements.

Skill for Claude CodeCodex

not rated 1.7k +1 yesterday A scan 57 tokens original Apache-2.0
View the source file JetBrains/MPS
About the project

JetBrains MPS is a development environment for creating domain-specific languages, which are programming languages designed for a particular field or task. It provides editors with features such as completion, semantic checks, and type checking, and can generate code in languages including Java and XML.

JetBrains/MPS · 1,658 stars · on GitHub

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/jetbrains/mps/mps-language-analysis
Any agent
npx skills add JetBrains/MPS --skill mps-language-analysis
Clone the repo
git clone --depth 1 https://github.com/JetBrains/MPS

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for mps-language-analysis

README.md
[![agentmods](https://agentmods.dev/badge/skills/jetbrains/mps/mps-language-analysis.svg)](https://agentmods.dev/skills/jetbrains/mps/mps-language-analysis)
Your own site
<a href="https://agentmods.dev/skills/jetbrains/mps/mps-language-analysis"><img src="https://agentmods.dev/badge/skills/jetbrains/mps/mps-language-analysis.svg" alt="Measured on agentmods" height="20"></a>
Per session 57 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 784 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00057 $0.00784
Opus 5 $0.00028 $0.00392
Sonnet 5 $0.00011 $0.00157
Haiku 4.5 $0.00006 $0.00078

Measured 5d ago against content hash 2c15f7ac74bb, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

mps-language-analysis scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.agents/skills/mps-language-analysis/SKILL.md · 51 lines

How it starts

The opening of the file, as written. The whole thing — 51 lines — stays where its author put it; the contents beside it link to each section on GitHub.

MPS Language Analysis

Workflow for inspecting an MPS language from a name (e.g. jetbrains.mps.lang.core). Returns concepts, metadata, structural info, and pointers to declarations and sample nodes.

Critical Directives

  • Use the fully qualified language name (e.g. jetbrains.mps.lang.core) — single-letter shorthand (j.m.l.core) requires resolution first via mps_mcp_get_project_structure.
  • For the qualifiedName returned by mps_mcp_get_concept_details, use it as the concept field in JSON blueprints. It is unambiguous.

Analyzing a Language by Name

  1. Verify Language: call mps_mcp_get_project_structure with the language name as a filter (startingPoint: My_Language). This confirms existence and provides the UUID.
  2. Retrieve Concepts: use mps_mcp_get_concept_details with the language name in languageRefs. Both conceptRefs and languageRefs accept either one value or a JSON-array string; omit the unused selector.
  3. Extract Data: the response includes:
    • Name: concept FQN.
    • Description: found in shortDescription.
    • Metadata: isRootable, isAbstract, and the conceptReference ID.
    • Structure: properties, children, and references are detailed here.
  4. Drill Down:
    • Declaration: use the sourceNode reference with mps_mcp_open_node to open the definition.
    • Examples: use mps_mcp_query_nodes with FIND_INSTANCES (sampleOnly: true) to get a sample node. Then use mps_mcp_print_node to see its canonical JSON structure for use as a template.
    • Inheritance: load the mps-language-inheritance skill for deeper hierarchy analysis.

Inspecting Concept Aspects

Use mps_mcp_query_structure with LIST_CONCEPT_ASPECTS to find associated definitions (Editor, Constraints, Behavior):

  • Direct Aspects: returns roots targeting the specific concept.
  • Inherited Aspects: set includeInherited: true to include aspects from ancestors (superconcepts/interfaces).
  • Editor Analysis:
    • ConceptEditorDeclaration: defines the full editor for the targetsConcept.
    • EditorComponentDeclaration: defines reusable presentation pieces.
    • Check the editor model in the response to identify available editors.

Read the full file on GitHub · 51 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 51 lines · 57 tokens per session scan A 2c15f7ac74bb

Subscribe to this mod's changes

mps-language-analysis is a skill published in the GitHub repository JetBrains/MPS (1,658 stars, last pushed yesterday), licensed Apache-2.0. It adds 57 tokens to every session and 784 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Languagesdomain-specific-languagedsl
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