[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"skill-jetbrains-android":3,"mdc--ewzrp2-key":34,"related-org-jetbrains-android":1294,"related-repo-jetbrains-android":1425},{"slug":4,"name":4,"fn":5,"description":6,"org":7,"tags":11,"stars":24,"repoUrl":25,"updatedAt":26,"license":27,"forks":28,"topics":29,"repo":30,"sourceUrl":32,"mdContent":33},"android","build Android applications with Kotlin","Senior Android engineer workflows — Kotlin-first (Java legacy supported), Jetpack Compose + View system, MVVM, Coroutines\u002FFlow, Room, Retrofit, Hilt, plus device orchestration via plugin tools (device management, logcat, crash reports, app run) and mobile-mcp for UI interaction (element tree, taps, swipes). 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Use when implementing features, debugging crashes, fixing builds, writing tests, reviewing Android code, or running QA on an emulator.\n---\n\n# Android\n\nSenior Android developer workflows. Covers both the **codebase layer** (Kotlin \u002F Compose \u002F MVVM \u002F Coroutines \u002F Room \u002F Retrofit) and the **device layer** (plugin tools for device management and diagnostics, mobile-mcp for UI interaction).\n\n> **Self-contained.** This skill does not require `kotlin-engineer`. All Kotlin\u002Fcoroutine rules relevant for Android are included here.\n\n## Reference Guide\n\n| Topic | Reference | Load When |\n|-------|-----------|-----------|\n| Implement a feature | `references\u002Fimplement.md` | Adding new screen \u002F feature \u002F data layer |\n| Jetpack Compose patterns | `references\u002Fcompose.md` | Compose UI, state, navigation, animation, Hilt, side effects |\n| View system \u002F XML UI | `references\u002Fview-system.md` | XML layouts, ViewBinding, RecyclerView, Fragments (legacy \u002F mixed projects) |\n| Debug a crash | `references\u002Fdebug.md` | Crash, unexpected behavior, stacktrace in logcat |\n| Fix a build | `references\u002Fbuild-fix.md` | Gradle error, compile error, KSP\u002FKAPT failure, resource error |\n| Write & run tests | `references\u002Ftest.md` | Unit tests (VM\u002FUseCase) or Compose\u002FEspresso UI tests |\n| Code review | `references\u002Freview.md` | Reviewing diff for leaks, threading, lifecycle, perf |\n| Manual QA on emulator | `references\u002Fqa.md` | Running scenarios on device, visual verification |\n| Device setup \u002F emulator bootstrap | `references\u002Fdevice-setup.md` | No device available, need to bring up an emulator |\n| Mobile MCP usage | `references\u002Fmobile-mcp.md` | Reading UI element tree, taps, swipes, text input via mobile-mcp |\n| ADB fallback | `references\u002Fadb.md` | Plugin tool \u002F mobile-mcp not available — use raw ADB shell as a last resort |\n| Accessibility | `references\u002Faccessibility.md` | Adding or reviewing UI — labels, touch targets, semantics, headings |\n\n## Google Official Skills\n\nFor specific migration or upgrade tasks, install the relevant Google Android skill into the project:\n\n```bash\n# See all available skills and their descriptions\nnpx android-skills-pack list\n\n# Install only if the skill is not already installed\nnpx android-skills-pack install --target junie --skill \u003Cname>\n```\n\nRelevant hints are in each reference file. When a task matches a Google skill, install it only if not already present.\n\n## Tool priority (three-tier fallback chain)\n\nUse the first available layer for any device\u002Fapp operation:\n\n1. **Plugin tools — first choice.** Device management (list\u002Fstart\u002Fstop emulator, list AVDs), app lifecycle (build\u002Finstall\u002Flaunch\u002Fclear), diagnostics (logcat, last crash, ANR traces), system tweaks (permissions, network, dark mode), Compose preview rendering. Fastest, structured output, no shell parsing needed.\n2. **mobile-mcp — UI interaction only.** Reading the UI element tree, taps, swipes, text input, back\u002Fhome, orientation, opening URLs, screenshot fallback. Use it when the action involves interacting with the UI surface.\n3. **ADB shell — last-resort fallback.** Only when neither a plugin tool nor mobile-mcp covers the operation, or when one of them is unavailable. See `references\u002Fadb.md`.\n\n## The core loop\n\nWhenever the agent touches the device, it follows this loop — no blind actions:\n\n```\nread UI element tree (mobile-mcp)        → observe current state (text, ids, bounds)\n     ↓\naction (mobile-mcp: tap \u002F swipe \u002F type \u002F press button)\n     ↓\nread UI element tree (mobile-mcp)        → verify UI changed as expected\n     ↓\nread logcat (plugin tool)                → catch silent crashes\n```\n\nThe element tree is the primary observation channel — it returns structured data (text, resource-id, bounds) that the agent can read directly without vision. A screenshot is a **fallback only**: use it when elements are missing from the tree (custom-drawn views, games, WebView content, visual layout issues).\n\n## Before running on device — verify Compose UI via headless preview\n\nFor any UI-touching task (Compose), render `@Preview` composables **before** running on the emulator:\n\n- **`display_android_compose_preview(path)`** — when the file path is known (typical case after editing a file).\n- **`read_android_last_preview`** (no args) — when the file is already open in the editor and the path is not known.\n\nBoth return one image per `@Preview` and trigger a build if needed. Only proceed to the emulator after the preview looks right.\n\n## Key Patterns\n\n### MVVM + UDF (Compose)\n\n```kotlin\n\u002F\u002F State — what's on screen right now\nsealed interface UserUiState {\n    data object Loading : UserUiState\n    data class Success(val user: User) : UserUiState\n    data class Error(val message: String) : UserUiState\n}\n\n\u002F\u002F ViewModel — no Context, no View, no Activity\nclass UserViewModel(\n    private val repo: UserRepository,\n) : ViewModel() {\n    private val _state = MutableStateFlow\u003CUserUiState>(UserUiState.Loading)\n    val state: StateFlow\u003CUserUiState> = _state.asStateFlow()\n\n    fun load(id: String) = viewModelScope.launch {\n        _state.value = UserUiState.Loading\n        _state.value = runCatching { repo.user(id) }\n            .onFailure { if (it is CancellationException) throw it }  \u002F\u002F never swallow cancellation\n            .fold({ UserUiState.Success(it) }, { UserUiState.Error(it.message ?: \"Error\") })\n    }\n}\n\n\u002F\u002F Composable — observes state with lifecycle awareness\n@Composable\nfun UserScreen(vm: UserViewModel = hiltViewModel()) {\n    val state by vm.state.collectAsStateWithLifecycle()\n    when (val s = state) {\n        UserUiState.Loading     -> LoadingIndicator()\n        is UserUiState.Error    -> ErrorView(s.message) { vm.load(\"me\") }\n        is UserUiState.Success  -> UserContent(s.user)\n    }\n}\n```\n\nFull Repository \u002F Retrofit \u002F Fragment examples → `references\u002Fimplement.md`.\n\n## Output Format\n\nWhen implementing a feature:\n\n1. **Plan** — one sentence stating what changes and which layers are touched (UI \u002F ViewModel \u002F Repository \u002F data).\n2. **Code** — implement bottom-up: data layer → domain → ViewModel → UI. Follow existing architecture patterns.\n3. **Checklist** — confirm: no `Context` in ViewModel, flows collected with `collectAsStateWithLifecycle`, `runBlocking` not used on main thread, no hardcoded colors\u002Fdp.\n\nWhen reviewing code: call out MUST-DO \u002F MUST-NOT violations, lifecycle leaks, threading issues, and N+1 data fetches. Suggest minimal fixes.\n\nWhen running QA: follow the core loop — observe → act → verify. Delegate long scenarios to `android-qa-agent`.\n\n## Constraints\n\n**MUST DO:**\n- Use Kotlin, Jetpack Compose, MVVM, Coroutines\u002FFlow.\n- Prefer **plugin tools** for device management, app lifecycle, diagnostics (logcat, crashes, ANR), permissions, and system settings — they are the first-tier choice.\n- Use **mobile-mcp** for UI interaction: element tree, taps, swipes, text input, back\u002Fhome, orientation, open-url.\n- Fall back to raw **ADB** shell only when neither tier covers the operation (`references\u002Fadb.md`).\n- Wrap every UI action: read element tree → act → read element tree, then check logcat.\n- When unit-testing, mock at the `ApiService` \u002F `Dao` boundary so the Repository logic (cache-first, API fallback, error mapping) is actually exercised. 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}\n}\n",[700],{"type":40,"tag":82,"props":701,"children":702},{"__ignoreMap":411},[703,711,719,727,735,743,752,760,769,778,787,796,805,814,822,831,840,849,857,866,875,883,891,900,909,918,927,936,945,954,963,971],{"type":40,"tag":417,"props":704,"children":705},{"class":419,"line":28},[706],{"type":40,"tag":417,"props":707,"children":708},{},[709],{"type":45,"value":710},"\u002F\u002F State — what's on screen right now\n",{"type":40,"tag":417,"props":712,"children":713},{"class":419,"line":429},[714],{"type":40,"tag":417,"props":715,"children":716},{},[717],{"type":45,"value":718},"sealed interface UserUiState {\n",{"type":40,"tag":417,"props":720,"children":721},{"class":419,"line":450},[722],{"type":40,"tag":417,"props":723,"children":724},{},[725],{"type":45,"value":726},"    data object Loading : UserUiState\n",{"type":40,"tag":417,"props":728,"children":729},{"class":419,"line":460},[730],{"type":40,"tag":417,"props":731,"children":732},{},[733],{"type":45,"value":734},"    data 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Suggest minimal fixes.",{"type":40,"tag":47,"props":1064,"children":1065},{},[1066,1068,1074],{"type":45,"value":1067},"When running QA: follow the core loop — observe → act → verify. Delegate long scenarios to ",{"type":40,"tag":82,"props":1069,"children":1071},{"className":1070},[],[1072],{"type":45,"value":1073},"android-qa-agent",{"type":45,"value":578},{"type":40,"tag":91,"props":1076,"children":1078},{"id":1077},"constraints",[1079],{"type":45,"value":1080},"Constraints",{"type":40,"tag":47,"props":1082,"children":1083},{},[1084],{"type":40,"tag":53,"props":1085,"children":1086},{},[1087],{"type":45,"value":1088},"MUST DO:",{"type":40,"tag":639,"props":1090,"children":1091},{},[1092,1097,1109,1121,1140,1145,1172],{"type":40,"tag":542,"props":1093,"children":1094},{},[1095],{"type":45,"value":1096},"Use Kotlin, Jetpack Compose, MVVM, Coroutines\u002FFlow.",{"type":40,"tag":542,"props":1098,"children":1099},{},[1100,1102,1107],{"type":45,"value":1101},"Prefer ",{"type":40,"tag":53,"props":1103,"children":1104},{},[1105],{"type":45,"value":1106},"plugin tools",{"type":45,"value":1108}," for device management, app lifecycle, diagnostics (logcat, crashes, ANR), permissions, and system settings — they are the first-tier choice.",{"type":40,"tag":542,"props":1110,"children":1111},{},[1112,1114,1119],{"type":45,"value":1113},"Use ",{"type":40,"tag":53,"props":1115,"children":1116},{},[1117],{"type":45,"value":1118},"mobile-mcp",{"type":45,"value":1120}," for UI interaction: element tree, taps, swipes, text input, back\u002Fhome, orientation, open-url.",{"type":40,"tag":542,"props":1122,"children":1123},{},[1124,1126,1131,1133,1138],{"type":45,"value":1125},"Fall back to raw ",{"type":40,"tag":53,"props":1127,"children":1128},{},[1129],{"type":45,"value":1130},"ADB",{"type":45,"value":1132}," shell only when neither tier covers the operation (",{"type":40,"tag":82,"props":1134,"children":1136},{"className":1135},[],[1137],{"type":45,"value":366},{"type":45,"value":1139},").",{"type":40,"tag":542,"props":1141,"children":1142},{},[1143],{"type":45,"value":1144},"Wrap every UI action: read element tree → act → read element tree, then check logcat.",{"type":40,"tag":542,"props":1146,"children":1147},{},[1148,1150,1156,1158,1164,1166,1171],{"type":45,"value":1149},"When unit-testing, mock at the ",{"type":40,"tag":82,"props":1151,"children":1153},{"className":1152},[],[1154],{"type":45,"value":1155},"ApiService",{"type":45,"value":1157}," \u002F ",{"type":40,"tag":82,"props":1159,"children":1161},{"className":1160},[],[1162],{"type":45,"value":1163},"Dao",{"type":45,"value":1165}," boundary so the Repository logic (cache-first, API fallback, error mapping) is actually exercised. See ",{"type":40,"tag":82,"props":1167,"children":1169},{"className":1168},[],[1170],{"type":45,"value":256},{"type":45,"value":578},{"type":40,"tag":542,"props":1173,"children":1174},{},[1175],{"type":45,"value":1176},"Reuse existing architecture patterns; read 2–3 similar features before adding a new one.",{"type":40,"tag":47,"props":1178,"children":1179},{},[1180],{"type":40,"tag":53,"props":1181,"children":1182},{},[1183],{"type":45,"value":1184},"MUST NOT DO:",{"type":40,"tag":639,"props":1186,"children":1187},{},[1188,1193,1219,1231,1244,1257],{"type":40,"tag":542,"props":1189,"children":1190},{},[1191],{"type":45,"value":1192},"Write new files in Java (Kotlin for all new code; keep existing Java files in Java).",{"type":40,"tag":542,"props":1194,"children":1195},{},[1196,1198,1203,1204,1210,1211,1217],{"type":45,"value":1197},"Hold ",{"type":40,"tag":82,"props":1199,"children":1201},{"className":1200},[],[1202],{"type":45,"value":1039},{"type":45,"value":1049},{"type":40,"tag":82,"props":1205,"children":1207},{"className":1206},[],[1208],{"type":45,"value":1209},"View",{"type":45,"value":1049},{"type":40,"tag":82,"props":1212,"children":1214},{"className":1213},[],[1215],{"type":45,"value":1216},"Activity",{"type":45,"value":1218}," references in a ViewModel.",{"type":40,"tag":542,"props":1220,"children":1221},{},[1222,1224,1229],{"type":45,"value":1223},"Call ",{"type":40,"tag":82,"props":1225,"children":1227},{"className":1226},[],[1228],{"type":45,"value":1055},{"type":45,"value":1230}," on the main thread.",{"type":40,"tag":542,"props":1232,"children":1233},{},[1234,1236,1242],{"type":45,"value":1235},"Swallow exceptions with empty ",{"type":40,"tag":82,"props":1237,"children":1239},{"className":1238},[],[1240],{"type":45,"value":1241},"catch",{"type":45,"value":1243}," blocks.",{"type":40,"tag":542,"props":1245,"children":1246},{},[1247,1249,1255],{"type":45,"value":1248},"Hardcode dp\u002Fsp\u002Fcolors — use ",{"type":40,"tag":82,"props":1250,"children":1252},{"className":1251},[],[1253],{"type":45,"value":1254},"MaterialTheme",{"type":45,"value":1256}," \u002F theme tokens.",{"type":40,"tag":542,"props":1258,"children":1259},{},[1260,1262,1268],{"type":45,"value":1261},"Bypass failing tests with ",{"type":40,"tag":82,"props":1263,"children":1265},{"className":1264},[],[1266],{"type":45,"value":1267},"@Ignore",{"type":45,"value":1269},", skip flags, or weakened assertions.",{"type":40,"tag":91,"props":1271,"children":1273},{"id":1272},"dedicated-agent",[1274],{"type":45,"value":1275},"Dedicated agent",{"type":40,"tag":47,"props":1277,"children":1278},{},[1279,1281,1286],{"type":45,"value":1280},"For autonomous QA loops, delegate to the ",{"type":40,"tag":82,"props":1282,"children":1284},{"className":1283},[],[1285],{"type":45,"value":1073},{"type":45,"value":1287}," — it runs scenarios on the emulator and produces a structured PASS\u002FFAIL\u002FBLOCKED report without modifying source code.",{"type":40,"tag":1289,"props":1290,"children":1291},"style",{},[1292],{"type":45,"value":1293},"html .light .shiki span {color: var(--shiki-light);background: var(--shiki-light-bg);font-style: var(--shiki-light-font-style);font-weight: var(--shiki-light-font-weight);text-decoration: var(--shiki-light-text-decoration);}html.light .shiki span {color: var(--shiki-light);background: var(--shiki-light-bg);font-style: var(--shiki-light-font-style);font-weight: var(--shiki-light-font-weight);text-decoration: var(--shiki-light-text-decoration);}html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .dark .shiki span {color: var(--shiki-dark);background: var(--shiki-dark-bg);font-style: var(--shiki-dark-font-style);font-weight: var(--shiki-dark-font-weight);text-decoration: var(--shiki-dark-text-decoration);}html.dark .shiki span {color: var(--shiki-dark);background: var(--shiki-dark-bg);font-style: var(--shiki-dark-font-style);font-weight: var(--shiki-dark-font-weight);text-decoration: var(--shiki-dark-text-decoration);}",{"items":1295,"total":1424},[1296,1312,1321,1330,1341,1351,1364,1373,1382,1392,1401,1414],{"slug":1297,"name":1297,"fn":1298,"description":1299,"org":1300,"tags":1301,"stars":1309,"repoUrl":1310,"updatedAt":1311},"mps-aspect-accessories","configure JetBrains MPS module dependencies","Wire MPS module and model dependencies, used languages, used devkits, extended languages, runtime solutions, accessory models, and language\u002Fdependency versions. Use when adding\u002Fremoving module dependencies, importing languages or devkits into a model, declaring runtime solutions, or shipping accessory content visible to consumers without explicit import.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1302,1305,1308],{"name":1303,"slug":1304,"type":15},"Architecture","architecture",{"name":1306,"slug":1307,"type":15},"Configuration","configuration",{"name":22,"slug":23,"type":15},1650,"https:\u002F\u002Fgithub.com\u002FJetBrains\u002FMPS","2026-07-17T06:06:57.311661",{"slug":1313,"name":1313,"fn":1314,"description":1315,"org":1316,"tags":1317,"stars":1309,"repoUrl":1310,"updatedAt":1320},"mps-aspect-actions","define and edit MPS node factories","Use when defining or editing MPS node factories (the \"actions\" aspect) — `NodeFactories` roots, per-concept `NodeFactory` setup functions that initialize a freshly created node and optionally copy data from a replaced `sampleNode`, plus the actions aspect's `CopyPasteHandlers` and `PasteWrappers` roots. Reach for this skill when a substitution, side transform, completion replacement, or `add new initialized(...)` should preserve fields from the node it is replacing, or when defaults set in a constructor are not enough.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1318,1319],{"name":1303,"slug":1304,"type":15},{"name":22,"slug":23,"type":15},"2026-07-17T06:04:48.066901",{"slug":1322,"name":1322,"fn":1323,"description":1324,"org":1325,"tags":1326,"stars":1309,"repoUrl":1310,"updatedAt":1329},"mps-aspect-behavior","define and edit MPS concept behavior","Use when defining or editing MPS `ConceptBehavior` — per-concept methods (non-virtual \u002F virtual \u002F abstract \u002F static \u002F virtual static), constructors, virtual dispatch (MRO), super and interface-default calls (`super\u003CInterface>.method`), overriding methods from `lang.core.behavior` interfaces such as `ScopeProvider.getScope` \u002F `INamedConcept.getName` \u002F `BaseConcept.getPresentation`, calling sibling methods (`LocalBehaviorMethodCall`) and behavior methods from other aspects via `node.method(...)`. Reach for this skill whenever the task involves authoring or modifying `\u003Clang>\u002FlanguageModels\u002Fbehavior.mps`.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1327,1328],{"name":1303,"slug":1304,"type":15},{"name":22,"slug":23,"type":15},"2026-07-13T06:45:21.757084",{"slug":1331,"name":1331,"fn":1332,"description":1333,"org":1334,"tags":1335,"stars":1309,"repoUrl":1310,"updatedAt":1340},"mps-aspect-constraints","define JetBrains MPS language constraints","Use when defining or editing MPS language constraints — property validators \u002F setters \u002F getters, referent search scopes (imperative or inherited via `ScopeProvider.getScope`), `referentSetHandler` side effects, default-scope blocks, `canBeChild` \u002F `canBeParent` \u002F `canBeAncestor` \u002F `canBeRoot` placement rules, `defaultConcreteConcept` for abstract concepts, `set \u003Cread-only>` and `{name}` aliasing, and scope helpers (`SimpleRoleScope`, `ListScope`, `CompositeScope`, `HidingByNameScope`). Reach for this skill whenever the task involves authoring or modifying `\u003Clang>\u002FlanguageModels\u002Fconstraints.mps`.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1336,1337],{"name":1303,"slug":1304,"type":15},{"name":1338,"slug":1339,"type":15},"Code Analysis","code-analysis","2026-07-23T05:41:33.639365",{"slug":1342,"name":1342,"fn":1343,"description":1344,"org":1345,"tags":1346,"stars":1309,"repoUrl":1310,"updatedAt":1350},"mps-aspect-dataflow","define and debug MPS dataflow builders","Use when defining or debugging MPS dataflow builders for a concept — control\u002Fdata flow declarations that drive reachability analysis and variable-use checking. Covers DataFlowBuilderDeclaration, BuilderBlock, emit instructions (code for, jump, ifjump, label, read, write, ret, mayBeUnreachable), positions (AfterPosition, BeforePosition, LabelPosition), the jetbrains.mps.lang.dataFlow language, the NodeParameter implicit, BL+smodel usage inside builder bodies, and IBuilderMode for advanced analyses such as nullable\u002Fnon-null tracking.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1347],{"name":1348,"slug":1349,"type":15},"Data Analysis","data-analysis","2026-07-13T06:45:19.114674",{"slug":1352,"name":1352,"fn":1353,"description":1354,"org":1355,"tags":1356,"stars":1309,"repoUrl":1310,"updatedAt":1363},"mps-aspect-editor","define MPS editor layouts","Use when creating or changing MPS editor definitions — the overall workflow from scaffolding a `ConceptEditorDeclaration` through componentizing reusable `EditorComponentDeclaration`s, refining cell models and cell layouts, applying style sheets and indent-layout style items, wiring smart references, leveraging inheritance via super-concepts and interfaces, inspecting (`print_node_json`, `show_node_representation`) and validating (`check_root_node_problems`). Covers `jetbrains.mps.lang.editor` cell models (`CellModel_RefNode`\u002F`CellModel_RefNodeList`\u002F`CellModel_RefCell`\u002F`CellModel_Property`\u002F`CellModel_Constant`), layout choices, and JSON blueprints for common editor shapes. For the non-layout side (action maps, keymaps, transformation\u002Fsubstitute menus) use `mps-aspect-editor-menus-and-keymaps`.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1357,1360],{"name":1358,"slug":1359,"type":15},"Design","design",{"name":1361,"slug":1362,"type":15},"UI Components","ui-components","2026-07-23T05:41:56.638151",{"slug":1365,"name":1365,"fn":1366,"description":1367,"org":1368,"tags":1369,"stars":1309,"repoUrl":1310,"updatedAt":1372},"mps-aspect-editor-menus-and-keymaps","author MPS editor menus and keymaps","Use when authoring the **non-layout** parts of the MPS editor aspect — what happens when the user types, presses a key, triggers completion, pastes, or invokes a context action. Covers action maps (`CellActionMapDeclaration`), cell keymaps (`CellKeyMapDeclaration`), transformation menus (`TransformationMenu_Default` \u002F `_Named` \u002F `_Contribution`), substitute menus (`SubstituteMenu_Default` \u002F `SubstituteMenu` \u002F contributions), side transforms (LEFT\u002FRIGHT), legacy cell menus, paste wrappers and copy-paste handlers (in the actions language), completion styling, reference presentation, two-step deletion, and the editor selection API. Trigger terms: `actionMap`, `keyMap`, `delete_action_id`, `transformationMenu`, `substituteMenu`, `Ctrl+Space`, `Ctrl+Alt+B`, side transform, paste wrapper, completion styling, `PasteWrappers`, `CopyPasteHandlers`. For the **layout** side (cells, layouts, style sheets) use `mps-aspect-editor` instead.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1370,1371],{"name":22,"slug":23,"type":15},{"name":1361,"slug":1362,"type":15},"2026-07-23T05:41:49.666535",{"slug":1374,"name":1374,"fn":1375,"description":1376,"org":1377,"tags":1378,"stars":1309,"repoUrl":1310,"updatedAt":1381},"mps-aspect-generation-plan","modify MPS generation plans","Use when defining or modifying an MPS generation plan — explicit ordering of generators, checkpoints for cross-model reference resolution, forks for parallel branches, IncludePlan composition, conditional PlanContribution activation, ParameterEquals\u002FConceptListSelector fork selectors, and InitModelAttributes for targetFacet routing. Apply when working with @genplan models, the jetbrains.mps.lang.generator.plan language, attaching plans via DevKits or the Custom generation facet, or debugging cross-model mapping label resolution.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1379,1380],{"name":1303,"slug":1304,"type":15},{"name":22,"slug":23,"type":15},"2026-07-13T06:44:59.507855",{"slug":1383,"name":1383,"fn":1384,"description":1385,"org":1386,"tags":1387,"stars":1309,"repoUrl":1310,"updatedAt":1391},"mps-aspect-generator","define JetBrains MPS generator rules","Use when defining or modifying MPS generators — author a generator module, add or edit root\u002Freduction\u002Fweaving\u002Fpattern mapping rules, attach template macros ($COPY_SRC, $LOOP, $IF, $PROPERTY, $REF, $SWITCH, $MAP_SRC, $WEAVE, $INSERT, $LABEL, $TRACE, $VAR), wire mapping labels, build template switches, write pre\u002Fpost mapping scripts, navigate `genContext`, or debug \"rule didn't fire\", missing references, empty output, infinite reduction loops, and generated-Java compile failures.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1388,1389,1390],{"name":1303,"slug":1304,"type":15},{"name":1338,"slug":1339,"type":15},{"name":22,"slug":23,"type":15},"2026-07-17T06:06:58.042999",{"slug":1393,"name":1393,"fn":1394,"description":1395,"org":1396,"tags":1397,"stars":1309,"repoUrl":1310,"updatedAt":1400},"mps-aspect-intentions","define and edit MPS intentions","Use when defining or editing MPS intentions (the Alt+Enter context-action aspect) — adding `IntentionDeclaration` roots, parameterized or surround-with variants, description\u002FisApplicable\u002Fexecute blocks, child-filter functions, factory-initialized AST splicing, or debugging why an intention is not offered. Lives in the language's `intentions` model and uses `jetbrains.mps.lang.intentions`.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1398,1399],{"name":1303,"slug":1304,"type":15},{"name":22,"slug":23,"type":15},"2026-07-23T05:41:48.692899",{"slug":1402,"name":1402,"fn":1403,"description":1404,"org":1405,"tags":1406,"stars":1309,"repoUrl":1310,"updatedAt":1413},"mps-aspect-migrations","author and debug MPS migration scripts","Use when authoring or debugging MPS migration scripts that upgrade user models after a language definition changes — covers jetbrains.mps.lang.migration (MigrationScript class-based, PureMigrationScript declarative, MoveConcept\u002FMoveContainmentLink\u002FMoveReferenceLink\u002FMoveProperty, ordering via OrderDependency, data exchange via putData\u002FgetData, RefactoringLog, ConceptMigrationReference) and jetbrains.mps.lang.script Enhancement Scripts (MigrationScript with MigrationScriptPart_Instance, ExtractInterfaceMigration, FactoryMigrationScriptPart, CommentMigrationScriptPart) — when a model needs version-gated upgrade, concept rename or removal, link or property rename, instance-level transformation, or composition of migration steps.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1407,1410],{"name":1408,"slug":1409,"type":15},"Debugging","debugging",{"name":1411,"slug":1412,"type":15},"Migration","migration","2026-07-13T06:45:20.372122",{"slug":1415,"name":1415,"fn":1416,"description":1417,"org":1418,"tags":1419,"stars":1309,"repoUrl":1310,"updatedAt":1423},"mps-aspect-structure-concepts","define concepts in MPS structure aspect","Define concepts, interface concepts, enumerations, and constrained data types in an MPS language's `structure` aspect. Covers smart-reference detection, alias rules, cardinality, INamedConcept usage, bulk creation, and the full `mps_mcp_alter_structure` \u002F `mps_mcp_query_structure` reference. Use when authoring or modifying a language's structure model.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1420],{"name":1421,"slug":1422,"type":15},"Data Modeling","data-modeling","2026-07-23T05:41:30.705975",188,{"items":1426,"total":771},[1427,1434,1449,1461,1472,1489,1499],{"slug":4,"name":4,"fn":5,"description":6,"org":1428,"tags":1429,"stars":24,"repoUrl":25,"updatedAt":26},{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1430,1431,1432,1433],{"name":17,"slug":4,"type":15},{"name":22,"slug":23,"type":15},{"name":13,"slug":14,"type":15},{"name":19,"slug":20,"type":15},{"slug":1435,"name":1435,"fn":1436,"description":1437,"org":1438,"tags":1439,"stars":24,"repoUrl":25,"updatedAt":1448},"context7","search library and framework documentation","Up-to-date library and framework documentation via Context7 MCP. Use when setup, API, or version-specific questions require current documentation.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1440,1443,1446],{"name":1441,"slug":1442,"type":15},"Documentation","documentation",{"name":1444,"slug":1445,"type":15},"MCP","mcp",{"name":119,"slug":1447,"type":15},"reference","2026-07-17T06:07:06.49579",{"slug":1450,"name":1450,"fn":1451,"description":1452,"org":1453,"tags":1454,"stars":24,"repoUrl":25,"updatedAt":1460},"java-engineer","write and refactor modern Java code","Java 17–25 policy and pitfalls. Use when writing, reviewing, or refactoring Java code — enforces idioms around records, sealed types, switch exhaustiveness, Optional, virtual threads, and null-safety that LLMs frequently get wrong.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1455,1456,1457],{"name":1338,"slug":1339,"type":15},{"name":22,"slug":23,"type":15},{"name":1458,"slug":1459,"type":15},"Java","java","2026-07-13T06:45:44.594223",{"slug":87,"name":87,"fn":1462,"description":1463,"org":1464,"tags":1465,"stars":24,"repoUrl":25,"updatedAt":1471},"write and refactor Kotlin code","Kotlin 2.x policy and pitfalls. Use when writing, reviewing, or refactoring Kotlin code — enforces coroutine-safety, Flow correctness, null-safety, and API-design rules that LLMs frequently get wrong.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1466,1469,1470],{"name":1467,"slug":1468,"type":15},"Code Review","code-review",{"name":22,"slug":23,"type":15},{"name":13,"slug":14,"type":15},"2026-07-13T06:45:30.911318",{"slug":1473,"name":1473,"fn":1474,"description":1475,"org":1476,"tags":1477,"stars":24,"repoUrl":25,"updatedAt":1488},"laravel-engineer","build and architect Laravel applications","Use when working on Laravel projects. Covers architecture decisions (Services vs Actions), thin controllers, Form Requests, API Resources, and API versioning. Enforces Larastan verification after code generation.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1478,1481,1482,1485],{"name":1479,"slug":1480,"type":15},"Backend","backend",{"name":22,"slug":23,"type":15},{"name":1483,"slug":1484,"type":15},"Laravel","laravel",{"name":1486,"slug":1487,"type":15},"PHP","php","2026-07-13T06:45:47.16012",{"slug":1490,"name":1490,"fn":1491,"description":1492,"org":1493,"tags":1494,"stars":24,"repoUrl":25,"updatedAt":1498},"php-engineer","write and refactor modern PHP code","Modern PHP 8.x policy and pitfalls. Use when writing, reviewing, or refactoring PHP code — enforces strict types, enum\u002Freadonly\u002Fmatch\u002FDNF policy, PHPStan discipline, and catches the subtle traps (type coercion, mixed abuse, readonly mutation through references, enum serialization, fiber lifecycle, PDO emulation) that LLMs get wrong by default.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1495,1496,1497],{"name":1338,"slug":1339,"type":15},{"name":22,"slug":23,"type":15},{"name":1486,"slug":1487,"type":15},"2026-07-13T06:45:32.210657",{"slug":1500,"name":1500,"fn":1501,"description":1502,"org":1503,"tags":1504,"stars":24,"repoUrl":25,"updatedAt":1515},"redis-best-practices","implement Redis best practices","Redis policy & pitfalls — key naming, atomicity, TTL strategy, distributed locks, cache patterns, production traps. Use when designing Redis-backed caches, locks, queues, rate limiters, or sessions. Covers the traps LLMs get wrong by default: SETNX + EX (deprecated), KEYS on production, Pub\u002FSub no-persistence, HGETALL on big hashes, maxmemory-policy defaults, cluster hash tags, RDB fork memory.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":9},[1505,1508,1509,1512],{"name":1506,"slug":1507,"type":15},"Database","database",{"name":22,"slug":23,"type":15},{"name":1510,"slug":1511,"type":15},"Performance","performance",{"name":1513,"slug":1514,"type":15},"Redis","redis","2026-07-13T06:45:48.502742"]