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.
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.
npx agentmods add skills/jetbrains/mps/ssrnpx skills add JetBrains/MPS --skill ssrgit clone --depth 1 https://github.com/JetBrains/MPSWrote 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.
[](https://agentmods.dev/skills/jetbrains/mps/ssr)<a href="https://agentmods.dev/skills/jetbrains/mps/ssr"><img src="https://agentmods.dev/badge/skills/jetbrains/mps/ssr.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00025 | $0.00970 |
| Opus 5 | $0.00013 | $0.00485 |
| Sonnet 5 | $0.00005 | $0.00194 |
| Haiku 4.5 | $0.00003 | $0.00097 |
Grade A, and why
ssr scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
Structural Search and Replace
-
You must use terminal search (
ls,catandgrep) to read directory.idea. Do not use IDE search. -
The contents of structural search inspections is located in
.idea/inspectionProfiles/idea_default.xml -
Here is an example of a Structural Search and Replace inspection:
<replaceConfiguration name="Use Strings.areSameInstance instead of =="
description="Comparing Strings by references usually indicate a mistake, if you really need to do this (for performance reeasons or to implement "Sentinel" pattern), use Strings.areSameInstance method to make the intention explicit and get rid of warning."
suppressId="StringEqualitySSR"
problemDescriptor="Use !Strings.areSameInstance instead of '!=' if you really need to compare strings by reference"
text="$s1$ == $s2$" recursive="false" caseInsensitive="false" type="JAVA" pattern_context="default"
search_injected="false" reformatAccordingToStyle="false" shortenFQN="true"
replacement="com.intellij.openapi.util.text.Strings.areSameInstance($s1$, $s2$)">
<constraint name="__context__" within="" contains=""/>
<constraint name="s1" nameOfExprType="java\.lang\.String" within="" contains=""/>
<constraint name="s2" nameOfExprType="java\.lang\.String" within="" contains=""/>
</replaceConfiguration>
This node should be located under <inspection_tool class="SSBasedInspection" tag.
- Here is an example of a Structural Search inspection:
<searchConfiguration name="Raw coroutine scope creation" uuid="e11e9d2f-7cc2-3359-a78a-24f67cbe0850"
description="Coroutine scope should be created: <ul> <li>by a coroutine builder (<code>launch</code>, <code>async</code>, <code>runBlockingCancellable</code>);</li> <li>by a scoping function (<code>withContext</code>, <code>coroutineScope</code>, <code>supervisorScope</code>);</li> <li>by injecting it into a service constructor;</li> <li>by explicitly creating a child scope (<code>childScope</code>, <code>namedChildScope</code>)</li> </ul> "
suppressId="RAW_SCOPE_CREATION"
problemDescriptor="Raw scope might not be linked to any parent unintentionally (if passed context does not have any <code>Job</code>, or if passed <code>Job</code> does not have any parent). Use <code>namedChildScope()</code> on some existing scope instead. If no parent is actually intended, use <code>GlobalScope.namedScope()</code>."
text="CoroutineScope($args$)" recursive="true" caseInsensitive="true" type="Kotlin" pattern_context="default"
search_injected="false">
<constraint name="__context__" within="" contains=""/>
<constraint name="args" within="" contains=""/>
</searchConfiguration>
This node should be located under <inspection_tool class="SSBasedInspection" tag.
- To configure the scope of inspection, you need to make changes similar to this pattern, where class is UUID of the created replace configuration.
<inspection_tool class="e5d3c6f8-12ab-4cc9-8e51-8a8f1bd1c3e2" enabled="true" level="WARNING" enabled_by_default="false">
<scope name="IDE Testing Framework" level="WARNING" enabled="true"/>
<scope name="Tests" level="WARNING" enabled="true"/>
<scope name="test-framework" level="WARNING" enabled="true"/>
</inspection_tool>
- You must run
InspectionProfileConsistencyTestafter changing xml files
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.
- 4d ago First seen · 61 lines · 25 tokens per session scan A a4d05c554608
ssr is a skill published in the GitHub repository JetBrains/MPS (1,658 stars, last pushed today), licensed Apache-2.0. It adds 25 tokens to every session and 970 once invoked, about $0.0001 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.
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