New: 98,000+ skills indexed from GitHub repos with 100+ stars · every skill safety-checkedBrowse top skillsTop skills
Esc to closeBrowse all skills
Submit a skillBrowse skills
Submit a skillBrowse skills

Official agent skill

Mps Lang Core XML

by JetBrains in JetBrains/MPS

A skill your agent uses when authoring XML documents as MPS root nodes or building XML-generating generator templates with jetbrains.mps.core.xml — covers XmlFile, XmlDocument, prolog (XML…

OfficialApache-2.0Auto-check passed

Install Mps Lang Core XML

skills CLI
$ npx skills add JetBrains/MPS --skill mps-lang-core-xml -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI
$ gh skill install JetBrains/MPS mps-lang-core-xml --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy
$ git clone --depth 1 https://github.com/JetBrains/MPS.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.agents/skills/mps-lang-core-xml .claude/skills/mps-lang-core-xml && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Facts

Skill name
mps-lang-core-xml
GitHub stars
1.7k
Token cost
~1.2k tokens
SKILL.md length
525 words
Files
5 (incl. references)
Skills in repo
41
Repo updated
First seen
Licence
Apache-2.0

At a glance

A skill your agent uses when authoring XML documents as MPS root nodes or building XML-generating generator templates with jetbrains.mps.core.xml — covers XmlFile, XmlDocument, prolog (XML…

  • Works in 6 steps: Add jetbrains.mps.core.xml as a used… → Create an XmlFile root node with a name.… → Add an XmlDocument child in role… → …
  • Authoring XML documents as MPS root nodes
  • SKILL.md covers Loading companion skills, Critical Directives, Common-Path Workflow and Related Skills, plus 1 more section
  • Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Mps Lang Core XML is an agent skill from JetBrains/MPS, published by the product's own GitHub organization. Use when authoring XML documents as MPS root nodes or building XML-generating generator templates with jetbrains.mps.core.xml — covers XmlFile, XmlDocument, prolog (XML declaration, DOCTYPE, processing instructions, comments), elements, attributes, CDATA, entity references, and macro attachment via the smodelAttribute role for templates that emit XML output.

Its SKILL.md is about 1.2k tokens, which your agent loads only when the skill is triggered. The skill folder holds 5 other files, including reference files (for example `references/concept-catalog.md`, `references/json-blueprints.md` and `references/language-dependencies.md`).

It works with JetBrains IDEs. The repository describes itself as: JetBrains Meta programming System. The licence is Apache-2.0.

When your agent uses it

  • Authoring XML documents as MPS root nodes
  • Building XML-generating generator templates with jetbrains.mps.core.xml — covers XmlFile
  • Prolog (XML declaration
  • Processing instructions

Example prompts

  • “/mps-lang-core-xml”

Workflow steps

6 steps, taken from the first numbered list in SKILL.md.

  1. Add jetbrains.mps.core.xml as a used language on the target model. For generator templates, also add jetbrains.mps.lang.generator.
  2. Create an XmlFile root node with a name. The name is the template/document identifier, not the output filename.
  3. Add an XmlDocument child in role document. Optionally add an XmlProlog for declarations/comments/PIs.
  4. Build the document tree under XmlDocument.rootElement and the inner content lists.
  5. For generator templates, attach RootTemplateAnnotation to the XmlFile via smodelAttribute, and attach macros (PropertyMacro, LoopMacro…
  6. Validate with mps_mcp_check_root_node_problems.

What it can do on your machine

Read from SKILL.md and the folder at commit 3e9cfcd. It shows what the files ask for, not the result of running them.

  • Tool permissions

    Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

    From allowed-tools in the SKILL.md frontmatter.

  • Runs code

    No scripts in the folder and no shell commands in SKILL.md.

    From the folder's file list and the shell code blocks in SKILL.md.

  • Network

    No URLs in SKILL.md.

    From URLs in SKILL.md, links to its own repository left out.

  • Credentials

    Names no API keys, tokens, secrets or passwords.

    From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Mps Lang Core XML loads about 1.2k tokens when it runs, and up to ~5.4k if it reads all its reference files. Until then it costs about 95 tokens; SKILL.md has 525 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it
~95
When it runs · the whole SKILL.md, loaded when a task matches
~1.2k
With references · SKILL.md plus every file in references/, read only if the agent opens them
~5.4k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from JetBrains/MPS at commit 3e9cfcd, republished under its Apache-2.0 licence (© JetBrains). 525 words, ~1,185 tokens.

Download SKILL.mdSave it as .claude/skills/mps-lang-core-xml/SKILL.md (or your agent's skills folder). This skill also uses 4 other files; get the full folder from GitHub.
name
mps-lang-core-xml
description
Use when authoring XML documents as MPS root nodes or building XML-generating generator templates with jetbrains.mps.core.xml — covers XmlFile, XmlDocument, prolog (XML declaration, DOCTYPE, processing instructions, comments), elements, attributes, CDATA, entity references, and macro attachment via the smodelAttribute role for templates that emit XML output.
type
reference

jetbrains.mps.core.xml Language

Loading companion skills

Companion names in this skill are lazy dependencies: load only those relevant to the current task. If this skill came from an MCP server, use the host's skill loader to resolve the companion's unique discovered entry URI on the same host-assigned originating server. If the host has no server-backed skill loader, stop and report that limitation; do not silently fall back to a filesystem copy. If this skill came from a filesystem catalog, load the named sibling from that same catalog at <skills-root>/<skill-name>/SKILL.md, even if remote skill loaders are also available. Do not invent a tool name or server endpoint.

jetbrains.mps.core.xml is an MPS language for authoring and generating XML documents inside MPS models. It is used either for direct XML authoring (an XmlFile root holds a complete document) or for generator templates (an XmlFile carries RootTemplateAnnotation and macros via smodelAttribute child roles).

Language reference: l:479c7a8c-02f9-43b5-9139-d910cb22f298:jetbrains.mps.core.xml

Critical Directives

  • Wrap everything in XmlFile → XmlDocument. XmlFile is the only rootable concept. XmlDocument.rootElement has cardinality 1 — put the root there, not in content.
  • XmlProlog is optional (0..1). Omit it entirely when no prolog is needed.
  • Attribute values are lists of XmlValuePart. A plain string is a single XmlTextValue. An attribute with no value children renders as a valueless (boolean) attribute.
  • Property name asymmetry: XmlText / XmlSingleLineText use the property value. XmlTextValue (attribute value part) uses the property text. Do not swap them.
  • In generators, macros go in the smodelAttribute child role of the node they annotate — not as siblings in content or attributes.
  • Subclass the base types. Extend XmlBaseAttribute (not XmlAttribute) and XmlBaseElement (not XmlElement) when defining custom concepts for derived languages.
  • Do not hand-edit serialized .mps files. Use MPS MCP node tools for all changes.
Show full SKILL.md (238 more words)Show less

Common-Path Workflow

  1. Add jetbrains.mps.core.xml as a used language on the target model. For generator templates, also add jetbrains.mps.lang.generator.
  2. Create an XmlFile root node with a name. The name is the template/document identifier, not the output filename.
  3. Add an XmlDocument child in role document. Optionally add an XmlProlog for declarations/comments/PIs.
  4. Build the document tree under XmlDocument.rootElement and the inner content lists.
  5. For generator templates, attach RootTemplateAnnotation to the XmlFile via smodelAttribute, and attach macros (PropertyMacro, LoopMacro, CopySrcNodeMacro, …) to inner nodes via their smodelAttribute role.
  6. Validate with mps_mcp_check_root_node_problems.
  • mps-aspect-generator — for generator-side macro design that produces these XML templates.
  • mps-aspect-textgen — for the text-serialization layer that turns these XML trees into output files.
  • mps-node-editing — generic JSON-blueprint node creation/replacement workflow.

Reference Index

  • Concept catalog — open when you need exact concept names, properties, cardinalities, or aliases for any document, prolog, element, attribute, or content node. See references/concept-catalog.md.
  • JSON blueprint patterns — open when constructing or editing concrete XML trees as JSON for mps_mcp_insert_root_node_from_json, mps_mcp_update_node. Includes minimal files, prolog with declarations, DOCTYPE, comments, attributes, mixed values, CDATA, processing instructions, and a full generator-template example. See references/json-blueprints.md.
  • Rules and pitfalls — open when a node validates but the rendered XML is wrong, when attribute/value naming feels inconsistent, or before subclassing element/attribute concepts. See references/rules-and-pitfalls.md.
  • Language dependencies — open when setting up a new model that uses XML concepts, or when wiring generator templates that mix XML with generator macros. See references/language-dependencies.md.

© JetBrains, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 4 other files (references) in .agents/skills/mps-lang-core-xml of JetBrains/MPS.

  • SKILL.md
  • references/concept-catalog.md
  • references/json-blueprints.md
  • references/language-dependencies.md
  • references/rules-and-pitfalls.md

Open the folder on GitHubat commit 3e9cfcd

Compare with similar skills

Mps Lang Core XML next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Mps Lang Core XML compared with similar skills
SkillStarsUsed inTokensAuto-checkLicenceRepo updated
Mps Lang Core XML this skillJetBrains/MPS1.7k—~1.2kAutomated safety check: PassApache-2.0
Doc SyncJetBrains/ideavim10k2 repos~2.6kAutomated safety check: PassMIT
Evals Contextzgsm-ai/costrict4.4k1 repos~1.9kAutomated safety check: PassApache-2.0
ChangelogJetBrains/ideavim10k1 repos~2.7kAutomated safety check: PassMIT
Youtrack CommunityJetBrains/intellij-community21k—~3.2kAutomated safety check: NotesCustom licence
Compose Multiplatform Patternsmonta-app/ocpp-emulator1805 repos~2kAutomated safety check: PassApache-2.0

Similar skills

  • Doc Sync

    JetBrains/ideavim

    Official

    Keeps IdeaVim documentation in sync with code changes. An agent skill from JetBrains/ideavim.

    10k GitHub starsUsed in 2 repos~2.6k tokens
    DevelopmentAuto-check passed

  • Evals Context

    zgsm-ai/costrict

    Provides context about the CoStrict evals system structure in this monorepo.

    4.4k GitHub starsUsed in 1 repo~1.9k tokens
    AI & LLM EngineeringAuto-check passed

  • Changelog

    JetBrains/ideavim

    Official

    Maintains the IdeaVim changelog (CHANGES.md). An agent skill from JetBrains/ideavim.

    10k GitHub starsUsed in 1 repo~2.7k tokens
    DevelopmentAuto-check passed

  • Youtrack Community

    JetBrains/intellij-community

    Official

    YouTrack CLI for a community checkout; the monorepo uses youtrack.

    21k GitHub stars~3.2k tokensUpdated today
    DevelopmentAuto-check: notes

  • Compose Multiplatform Patterns

    monta-app/ocpp-emulator

    Compose Multiplatform and Jetpack Compose patterns for KMP projects — state management, navigation, theming, performance, and platform-specific UI.

    180 GitHub starsUsed in 5 repos~2k tokens
    MobileAuto-check passed

  • Compare Python Typecheckers

    JetBrains/intellij-community

    Official

    Compare Python type inference with ty, pyrefly, and basedpyright.

    21k GitHub stars~617 tokensUpdated today
    Auto-check passed

More from JetBrains/MPS

All 41 skills in this repo

  • Mps Language Analysis

    JetBrains/MPS

    Official

    Analyze an MPS language by name — discover concepts, properties, references, children, aspects (editor/constraints/behavior), metadata, and answer type questions (is A a subtype of B, common…

    1.7k GitHub stars~1.8k tokensUpdated today
    Auto-check passed

  • Mps Node Editing

    JetBrains/MPS

    Official

    Add, update, or delete MPS nodes using JSON blueprints — covers the unified blueprint format, staged construction for large subtrees, validation, and reference repair.

    1.7k GitHub stars~5.1k tokensUpdated today
    Auto-check passed

  • Mps Project Management

    JetBrains/MPS

    Official

    Open an MPS project in a running or freshly started MPS instance when MCP tools fail because no project is open (welcome screen), close an open project with mpsmcpcloseproject, or create a new empty…

    1.7k GitHub stars~2.2k tokensUpdated today
    Auto-check passed

  • Mps MCP Workflow

    JetBrains/MPS

    Official

    Complete JetBrains MPS workflow guide for DSL projects — models, languages, generators, node JSON blueprints, type queries, validation, MPS MCP tool usage, and the index of companion skills.

    1.7k GitHub stars~6.6k tokensUpdated today
    Auto-check passed

  • Bugfix Workflow

    JetBrains/MPS

    Official

    Structured MPS bugfix workflow driven by a YouTrack issue ID — preflight tool checks, version/branch derivation, parallel-agent problem analysis, solution design, branch creation, implementation…

    1.7k GitHub stars~4.4k tokensUpdated today
    Auto-check passed

  • Mps Aspect Structure Concepts

    JetBrains/MPS

    Official

    Define concepts, interface concepts, enumerations, and constrained data types in an MPS language's structure aspect.

    1.7k GitHub stars~2.8k tokensUpdated today
    Auto-check passed

Works with

Questions about Mps Lang Core XML

What does Mps Lang Core XML do?

A skill your agent uses when authoring XML documents as MPS root nodes or building XML-generating generator templates with jetbrains.mps.core.xml — covers XmlFile, XmlDocument, prolog (XML…. Mps Lang Core XML is an agent skill from JetBrains/MPS, published by the product's own GitHub organization.xml — covers XmlFile, XmlDocument, prolog (XML declaration, DOCTYPE, processing instructions, comments), elements, attributes, CDATA, entity references, and macro attachment via the smodelAttribute role for templates that emit XML output.

When should I use Mps Lang Core XML?

Mps Lang Core XML fits situations like: authoring XML documents as MPS root nodes; building XML-generating generator templates with jetbrains.mps.core.xml — covers XmlFile; prolog (XML declaration; processing instructions.

How do I install Mps Lang Core XML in Claude Code?

Run `npx skills add JetBrains/MPS --skill mps-lang-core-xml -a claude-code`. Or copy the skill folder (.agents/skills/mps-lang-core-xml in JetBrains/MPS) into .claude/skills/mps-lang-core-xml in your project. Claude Code loads it when a task matches its description.

How do I install Mps Lang Core XML in Codex?

Run `npx skills add JetBrains/MPS --skill mps-lang-core-xml -a codex`. Or copy the skill folder (.agents/skills/mps-lang-core-xml in JetBrains/MPS) into .agents/skills/mps-lang-core-xml in your project. Codex loads it when a task matches its description.

Can I use Mps Lang Core XML in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add JetBrains/MPS --skill mps-lang-core-xml -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/mps-lang-core-xml, .gemini/skills/mps-lang-core-xml, .github/skills/mps-lang-core-xml and .opencode/skills/mps-lang-core-xml in your project.

What does Mps Lang Core XML need to run?

SKILL.md names no scripts, command-line tools or credentials: Mps Lang Core XML is instructions for the agent only.

Does Mps Lang Core XML access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Mps Lang Core XML safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Mps Lang Core XML use?

Mps Lang Core XML is published under the Apache-2.0 licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Mps Lang Core XML use?

About 1.2k tokens (SKILL.md is roughly 4.7k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 4.2k tokens, read only when the agent opens those files.

What are the alternatives to Mps Lang Core XML?

Skills that share tags, products or a category with Mps Lang Core XML: Doc Sync (JetBrains/ideavim, 10k stars), Evals Context (zgsm-ai/costrict, 4.4k stars), Changelog (JetBrains/ideavim, 10k stars) and Youtrack Community (JetBrains/intellij-community, 21k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Mps Lang Core XML?

JetBrains (a GitHub organization, an official publisher) maintains it in JetBrains/MPS, which has 1,661 GitHub stars. The repository holds 41 skills in this directory. The repository was last updated on October 8, 2026.

Source: JetBrains/MPS on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.