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Use when asked \"when did this last fail\", \"failure history\", \"failure rate\", \"is this issue still active\", \"flaky test history\", \"known issue activity\", or \"most active known issues\".\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},"dotnet",".NET (Microsoft)","https:\u002F\u002Fpexgzepcugksgbtrxkhf.supabase.co\u002Fstorage\u002Fv1\u002Fobject\u002Fpublic\u002Forg-logos\u002Fdotnet.png",[12,16,19,22],{"name":13,"slug":14,"type":15},".NET","net","tag",{"name":17,"slug":18,"type":15},"Analytics","analytics",{"name":20,"slug":21,"type":15},"Code Analysis","code-analysis",{"name":23,"slug":24,"type":15},"Debugging","debugging",12,"https:\u002F\u002Fgithub.com\u002Fdotnet\u002Farcade-skills","2026-07-12T08:21:48.106854",null,18,[],{"repoUrl":26,"stars":25,"forks":29,"topics":32,"description":33},[],"Reuseable AI skills, plugins, agents for use in the dotnet product repos, such as dotnet\u002Fruntime","https:\u002F\u002Fgithub.com\u002Fdotnet\u002Farcade-skills\u002Ftree\u002FHEAD\u002Fplugins\u002Fdotnet-dnceng\u002Fskills\u002Fknown-issue-history","---\nname: known-issue-history\ndescription: >\n  Analyze historical failure rates for Known Build Error issues by mining the\n  edit history of issue bodies. Use when asked \"when did this last fail\",\n  \"failure history\", \"failure rate\", \"is this issue still active\",\n  \"flaky test history\", \"known issue activity\", or \"most active known issues\".\n---\n\n# Known Build Error History Analysis\n\nReconstruct failure timelines for \"Known Build Error\" issues by analyzing the edit history of the issue body's hit count table. The `build-analysis` bot periodically edits these issues to update rolling hit counts (24h\u002F7d\u002F1mo) — this skill mines those edits to recover the full failure history.\n\n## When to Use This Skill\n\nUse this skill when:\n- Investigating whether a known issue is still actively failing (\"when did this last fail?\")\n- Checking failure frequency and trends for a flaky test\n- Triaging known issues — identifying which are dormant vs actively hitting\n- Deciding whether to close a known issue that appears inactive\n- Scanning all open known issues to find the most problematic ones\n\n## Workflow Steps\n\n### Single Issue Analysis\n\n1. Determine the issue number and repository from the user's request\n2. Run the script: `.\u002Fscripts\u002FGet-KnownIssueHistory.ps1 -IssueNumber \u003CN> -Repository \u003Cowner\u002Frepo>`\n3. Add `-Since \u003Cdate>` if the user only wants recent failures, or `-Json` for structured output\n4. Summarize the results: total failure events, failure periods, last failure date, and days since last failure\n5. If posting results to an issue or PR, include a link to this skill (see Posting Results below)\n\n### Scanning All Active Known Issues\n\n1. Run the script: `.\u002Fscripts\u002FGet-KnownIssueHistory.ps1 -ListActive -Repository \u003Cowner\u002Frepo>`\n2. Add `-MaxIssues \u003CN>` to limit scope (default 50, max 100)\n3. Summarize the ranked table highlighting the most actively failing issues and any dormant candidates for closing\n\n## Quick Start\n\n```powershell\n# Analyze a single known issue\n.\u002Fscripts\u002FGet-KnownIssueHistory.ps1 -IssueNumber 100088\n\n# Only show recent failures\n.\u002Fscripts\u002FGet-KnownIssueHistory.ps1 -IssueNumber 100088 -Since 2025-01-01\n\n# JSON output for programmatic use\n.\u002Fscripts\u002FGet-KnownIssueHistory.ps1 -IssueNumber 100088 -Json\n\n# Scan all open Known Build Error issues, ranked by activity\n.\u002Fscripts\u002FGet-KnownIssueHistory.ps1 -ListActive\n\n# Different repository\n.\u002Fscripts\u002FGet-KnownIssueHistory.ps1 -IssueNumber 12345 -Repository dotnet\u002Faspnetcore\n```\n\n## Key Parameters\n\n| Parameter | Description |\n|-----------|-------------|\n| `-IssueNumber` | Known Build Error issue number to analyze |\n| `-Repository` | Target repo in `owner\u002Frepo` format (default: `dotnet\u002Fruntime`) |\n| `-ListActive` | Scan all open Known Build Error issues and rank by recent activity |\n| `-MaxIssues` | Max issues to scan in ListActive mode (default: 50) |\n| `-Since` | Only show failures after this date (ISO 8601, e.g. `2025-01-01`) |\n| `-Json` | Output structured JSON (`[KNOWN_ISSUE_HISTORY]` block) instead of table |\n\n## Modes\n\n### Single Issue Mode (`-IssueNumber`)\n\nQueries the GitHub GraphQL `userContentEdits` API for the issue, parses each edit's hit count table, and detects failure events by tracking when the 24-hour count transitions from 0 to a positive value.\n\n**Output includes:**\n- **Failure summary** — total failure events, failure periods, last failure date, days since last failure\n- **Failure periods** — clusters of failures grouped by the gap between all-clear events, with peak hit counts\n- **Edit timeline** — chronological table of every hit count snapshot with failure event markers\n\n### List Active Mode (`-ListActive`)\n\nScans all open issues with the \"Known Build Error\" label in the repository and analyzes each one's edit history. Outputs a ranked table sorted by most recent failure.\n\nUse this to find:\n- Which known issues are still actively failing\n- Which known issues haven't failed in months (candidates for closing)\n- Overall flaky test health of the repository\n\n## Interpreting Results\n\n### Failure Events\n\n| Marker | Meaning |\n|--------|---------|\n| `\u003C-- NEW FAILURE` | 24h count went from 0 to N — a build just matched this known issue |\n| `\u003C-- ADDITIONAL FAILURE` | 24h count increased — another build matched within 24 hours |\n| `(cleared)` | All counts returned to 0 — no recent matches |\n\n### Failure Periods\n\nConsecutive failure events are grouped into periods. A period starts when 24h goes from 0→N and ends when all counts return to 0.\n\n- **Many short periods** → intermittently flaky test\n- **One long period** → sustained regression\n- **Peak 24h count** → severity indicator (1 = occasional, higher = frequent across builds)\n\n### Triage Guidelines\n\n| Days Since Last Failure | Status | Action |\n|------------------------|--------|--------|\n| 0-7 | Actively failing | Needs investigation |\n| 7-30 | Recently active | Monitor |\n| 30-90 | Dormant | Consider closing |\n| 90+ | Likely fixed | Recommend closing |\n\n### Posting Results\n\nWhen posting results to an issue or PR comment, always include a link back to this skill so readers know where the analysis came from:\n\n```\nAnalysis generated by [known-issue-history](https:\u002F\u002Fgithub.com\u002Fdotnet\u002Farcade-skills\u002Ftree\u002Fmain\u002Fplugins\u002Fdotnet-dnceng\u002Fskills\u002Fknown-issue-history)\n```\n\n## How It Works\n\nThe `build-analysis` bot edits Known Build Error issue bodies whenever hit counts change. GitHub stores the revision history via the GraphQL `userContentEdits` API. Each edit includes a diff showing what changed in the issue body. The script parses hit-count table rows from these diffs to reconstruct snapshots:\n\n```markdown\n|24-Hour Hit Count|7-Day Hit Count|1-Month Count|\n|---|---|---|\n|0|0|0|\n```\n\nThe script extracts these snapshots chronologically and detects state transitions to reconstruct when failures actually occurred — recovering historical data that the rolling windows would otherwise hide.\n\n### Limitations\n\n- **Edit retention**: GitHub may not retain edits indefinitely for very old issues\n- **Polling frequency**: Edits occur when hit counts change, not on a fixed schedule — timestamps show when the bot detected changes, not the exact test failure time\n- **Rolling windows**: A single failure appears across multiple snapshots as it moves through the 24h→7d→1mo windows\n\n## References\n\n- **Detailed approach and interpretation**: See [references\u002Fknown-issue-history.md](references\u002Fknown-issue-history.md)\n- **Known Issues documentation**: See [dotnet\u002Farcade Known Issues guide](https:\u002F\u002Fgithub.com\u002Fdotnet\u002Farcade\u002Fblob\u002Fmain\u002FDocumentation\u002FProjects\u002FBuild%20Analysis\u002FKnownIssues.md)\n- **Build Analysis website**: https:\u002F\u002Fhelix.dot.net\u002FBuildAnalysis\n- **Known Issues board**: https:\u002F\u002Fgithub.com\u002Forgs\u002Fdotnet\u002Fprojects\u002F111\n",{"data":37,"body":38},{"name":4,"description":6},{"type":39,"children":40},"root",[41,50,65,72,77,107,113,120,171,177,207,213,349,355,515,521,533,546,555,588,600,605,610,628,634,640,713,719,724,757,763,862,868,873,883,889,908,995,1000,1006,1039,1045,1112],{"type":42,"tag":43,"props":44,"children":46},"element","h1",{"id":45},"known-build-error-history-analysis",[47],{"type":48,"value":49},"text","Known Build Error History Analysis",{"type":42,"tag":51,"props":52,"children":53},"p",{},[54,56,63],{"type":48,"value":55},"Reconstruct failure timelines for \"Known Build Error\" issues by analyzing the edit history of the issue body's hit count table. 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var(--shiki-dark-text-decoration);}",{"items":1119,"total":25},[1120,1135,1148,1163,1176,1193,1203],{"slug":1121,"name":1121,"fn":1122,"description":1123,"org":1124,"tags":1125,"stars":25,"repoUrl":26,"updatedAt":1134},"binskim-analysis","investigate BinSkim SDL security findings","Investigate BinSkim SDL findings from official pipelines — understand Guardian filtering, compare raw vs merged SARIF, decode portal results, and determine fix ownership. Use when asked about SDL scan results, portal findings, Guardian filtering, rule meanings, or discrepancies between local and official results. Also use when asked \"why does the portal show X\", \"what's filtered\", \"explain Guardian\", \"investigate SDL findings\", \"portal BA2008\", \"binskim failures in pipeline\", or \"what rules are required\". DO NOT USE FOR: running BinSkim locally (use binskim-scan), source code analysis (use CodeQL), or credential scanning (use CredScan).\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1126,1127,1130,1131],{"name":13,"slug":14,"type":15},{"name":1128,"slug":1129,"type":15},"Audit","audit",{"name":20,"slug":21,"type":15},{"name":1132,"slug":1133,"type":15},"Security","security","2026-07-12T08:23:11.212231",{"slug":1136,"name":1136,"fn":1137,"description":1138,"org":1139,"tags":1140,"stars":25,"repoUrl":26,"updatedAt":1147},"binskim-scan","run BinSkim binary security analysis","Run BinSkim binary security analysis locally against a dotnet repository. Use when asked to scan binaries, check BinSkim compliance, verify a fix for a rule violation, or run a local SDL scan. Also use when asked \"run binskim\", \"binary security scan\", \"scan binaries\", \"check binskim\", \"verify my fix\", \"repro BA2008 locally\", or \"verify BA2008 fix\". DO NOT USE FOR: investigating official pipeline results or portal findings (use binskim-analysis), source code analysis (use CodeQL), credential scanning (use CredScan), or general build\u002Ftest failures (use ci-analysis).\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1141,1142,1145,1146],{"name":13,"slug":14,"type":15},{"name":1143,"slug":1144,"type":15},"CLI","cli",{"name":20,"slug":21,"type":15},{"name":1132,"slug":1133,"type":15},"2026-07-12T08:23:09.911458",{"slug":1149,"name":1149,"fn":1150,"description":1151,"org":1152,"tags":1153,"stars":25,"repoUrl":26,"updatedAt":1162},"ci-analysis","analyze .NET CI build and test status","Analyze CI build and test status from Azure DevOps and Helix for dotnet repository PRs. Use when checking CI status, investigating failures, determining if a PR is ready to merge, or given URLs containing dev.azure.com or helix.dot.net. Also use when asked \"why is CI red\", \"test failures\", \"retry CI\", \"rerun tests\", \"is CI green\", \"build failed\", \"checks failing\", or \"flaky tests\". DO NOT USE FOR: investigating stale codeflow PRs or dependency update health, tracing whether a commit has flowed from one repo to another, reviewing code changes for correctness or style.\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1154,1155,1158,1161],{"name":13,"slug":14,"type":15},{"name":1156,"slug":1157,"type":15},"Azure","azure",{"name":1159,"slug":1160,"type":15},"CI\u002FCD","ci-cd",{"name":23,"slug":24,"type":15},"2026-07-12T08:21:49.360882",{"slug":1164,"name":1164,"fn":1165,"description":1166,"org":1167,"tags":1168,"stars":25,"repoUrl":26,"updatedAt":1175},"ci-crash-dump","debug CI crash dumps","Download and debug crash dumps from CI test failures in dotnet repositories. Use when a CI test crashed (not just failed), when the user wants to debug a crash dump from a PR or build, or when asked \"debug dump\", \"download dump\", \"crash dump from CI\", \"test crashed\", \"analyze crash in PR\", or \"why did the test crash\". DO NOT USE FOR: test failures that are not crashes (use ci-analysis), build failures, performance analysis, or analyzing dumps you already have locally.\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1169,1170,1171,1172],{"name":13,"slug":14,"type":15},{"name":1159,"slug":1160,"type":15},{"name":23,"slug":24,"type":15},{"name":1173,"slug":1174,"type":15},"Testing","testing","2026-07-12T08:21:56.945844",{"slug":1177,"name":1177,"fn":1178,"description":1179,"org":1180,"tags":1181,"stars":25,"repoUrl":26,"updatedAt":1192},"flow-analysis","analyze VMR codeflow health","Analyze VMR codeflow health using maestro MCP tools and GitHub MCP tools. USE FOR: investigating stale codeflow PRs, checking if fixes have flowed through the VMR pipeline, debugging dependency update issues, checking overall flow status for a repo, diagnosing why backflow PRs are missing or blocked, subscription health, build freshness, URLs containing dotnet-maestro or \"Source code updates from dotnet\u002Fdotnet\". DO NOT USE FOR: CI build failures (use ci-analysis skill), code review (use code-review skill), general PR investigation without codeflow context, tracing whether a specific commit\u002FPR has reached another repo (use flow-tracing skill). INVOKES: maestro and GitHub MCP tools, flow-health.cs script.\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1182,1183,1186,1189],{"name":1159,"slug":1160,"type":15},{"name":1184,"slug":1185,"type":15},"Engineering","engineering",{"name":1187,"slug":1188,"type":15},"GitHub","github",{"name":1190,"slug":1191,"type":15},"MCP","mcp","2026-07-12T08:21:53.151866",{"slug":1194,"name":1194,"fn":1195,"description":1196,"org":1197,"tags":1198,"stars":25,"repoUrl":26,"updatedAt":1202},"flow-tracing","trace .NET dependency flow in VMR","Trace dependency flow across .NET repos through the VMR pipeline. USE FOR: checking if a PR\u002Fcommit from repo A has reached repo B, finding what runtime SHA is in an SDK build, tracing dependency versions through the VMR, checking if a commit is included in an SDK build, decoding SDK version strings, \"has my fix reached runtime\", \"did roslyn#80873 flow to runtime\", \"what SHA is in SDK version X\", cross-repo dependency tracing, mapping SDK versions to VMR commits. DO NOT USE FOR: codeflow PR health or staleness (use flow-analysis skill), CI build failures (use ci-analysis skill). INVOKES: maestro and GitHub MCP tools, Get-SdkVersionTrace.ps1 script.\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1199],{"name":1200,"slug":1201,"type":15},"Data Pipeline","data-pipeline","2026-07-12T08:21:55.689056",{"slug":1204,"name":1204,"fn":1205,"description":1206,"org":1207,"tags":1208,"stars":25,"repoUrl":26,"updatedAt":1212},"helix-investigation","investigate Helix test failures","Deep-dive investigation of Helix test failures starting from AzDO build legs. USE FOR: investigating recurring Helix test failures, downloading and analyzing Helix console logs, comparing passing vs failing runs, identifying machine-specific issues, XHarness timeout analysis, Android emulator DEVICE_NOT_FOUND errors, bulk failure aggregation across legs, \"why does this test fail on some machines\", \"top 5 failing tests in the last 2 days\", \"download helix logs for build X\", \"compare passing and failing helix runs\", \"what are the most common failures\". DO NOT USE FOR: high-level CI status checks (use ci-analysis), codeflow PRs (use flow-analysis). INVOKES: Helix and AzDO MCP tools, curl, gh CLI.\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1209,1210,1211],{"name":23,"slug":24,"type":15},{"name":1184,"slug":1185,"type":15},{"name":1173,"slug":1174,"type":15},"2026-07-12T08:21:46.445586",{"items":1214,"total":1373},[1215,1229,1242,1257,1275,1287,1307,1317,1329,1339,1352,1363],{"slug":1216,"name":1216,"fn":1217,"description":1218,"org":1219,"tags":1220,"stars":1226,"repoUrl":1227,"updatedAt":1228},"multithreaded-task-migration","migrate MSBuild tasks to multithreaded mode","Guide for migrating MSBuild tasks to multithreaded mode support, including compatibility red-team review. Use this when converting tasks to thread-safe versions, implementing IMultiThreadableTask, adding TaskEnvironment support, or auditing migrations for behavioral compatibility.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1221,1222,1223],{"name":13,"slug":14,"type":15},{"name":1184,"slug":1185,"type":15},{"name":1224,"slug":1225,"type":15},"Performance","performance",5535,"https:\u002F\u002Fgithub.com\u002Fdotnet\u002Fmsbuild","2026-07-22T05:37:33.965588",{"slug":1230,"name":1230,"fn":1231,"description":1232,"org":1233,"tags":1234,"stars":1239,"repoUrl":1240,"updatedAt":1241},"analyzing-dotnet-performance","analyze .NET code for performance anti-patterns","Scans .NET code for ~50 performance anti-patterns across async, memory, strings, collections, LINQ, regex, serialization, and I\u002FO with tiered severity classification. Use when analyzing .NET code for optimization opportunities, reviewing hot paths, or auditing allocation-heavy patterns.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1235,1236,1237,1238],{"name":13,"slug":14,"type":15},{"name":20,"slug":21,"type":15},{"name":23,"slug":24,"type":15},{"name":1224,"slug":1225,"type":15},4576,"https:\u002F\u002Fgithub.com\u002Fdotnet\u002Fskills","2026-07-12T08:23:25.400375",{"slug":1243,"name":1243,"fn":1244,"description":1245,"org":1246,"tags":1247,"stars":1239,"repoUrl":1240,"updatedAt":1256},"android-tombstone-symbolication","symbolicate .NET runtime frames in Android tombstones","Symbolicate the .NET runtime frames in an Android tombstone file. Extracts BuildIds and PC offsets from the native backtrace, downloads debug symbols from the Microsoft symbol server, and runs llvm-symbolizer to produce function names with source file and line numbers. USE FOR triaging a .NET MAUI or Mono Android app crash from a tombstone, resolving native backtrace frames in libmonosgen-2.0.so or libcoreclr.so to .NET runtime source code, or investigating SIGABRT, SIGSEGV, or other native signals originating from the .NET runtime on Android. DO NOT USE FOR pure Java\u002FKotlin crashes, managed .NET exceptions that are already captured in logcat, or iOS crash logs. INVOKES Symbolicate-Tombstone.ps1 script, llvm-symbolizer, Microsoft symbol server.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1248,1249,1252,1253],{"name":13,"slug":14,"type":15},{"name":1250,"slug":1251,"type":15},"Android","android",{"name":23,"slug":24,"type":15},{"name":1254,"slug":1255,"type":15},"Microsoft","microsoft","2026-07-12T08:23:21.595572",{"slug":1258,"name":1258,"fn":1259,"description":1260,"org":1261,"tags":1262,"stars":1239,"repoUrl":1240,"updatedAt":1274},"apple-crash-symbolication","symbolicate .NET runtime frames in crash logs","Symbolicate .NET runtime frames in Apple platform .ips crash logs (iOS, tvOS, Mac Catalyst, macOS). Extracts UUIDs and addresses from the native backtrace, locates dSYM debug symbols, and runs atos to produce function names with source file and line numbers. Automatically downloads .dwarf symbols from the Microsoft symbol server using Mach-O UUIDs. USE FOR triaging a .NET MAUI or Mono app crash from an .ips file on any Apple platform, resolving native backtrace frames in libcoreclr or libmonosgen-2.0 to .NET runtime source code, retrieving .ips crash logs from a connected iOS device or iPhone, or investigating EXC_CRASH, EXC_BAD_ACCESS, SIGABRT, or SIGSEGV originating from the .NET runtime. DO NOT USE FOR pure Swift\u002FObjective-C crashes with no .NET components, or Android tombstone files. INVOKES Symbolicate-Crash.ps1 script, atos, dwarfdump, idevicecrashreport.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1263,1264,1265,1268,1271],{"name":13,"slug":14,"type":15},{"name":23,"slug":24,"type":15},{"name":1266,"slug":1267,"type":15},"iOS","ios",{"name":1269,"slug":1270,"type":15},"macOS","macos",{"name":1272,"slug":1273,"type":15},"Observability","observability","2026-07-12T08:23:20.369986",{"slug":1276,"name":1276,"fn":1277,"description":1278,"org":1279,"tags":1280,"stars":1239,"repoUrl":1240,"updatedAt":1286},"assertion-quality","evaluate assertion quality in test suites","Analyzes the variety and depth of assertions across test suites in any language. Use when the user asks to evaluate assertion quality, find shallow tests, identify assertion-free tests (no assertions or only trivial ones like Assert.IsNotNull \u002F toBeTruthy()), flag self-referential or tautological assertions, measure assertion diversity, or audit whether tests verify different facets of behavior. Polyglot: .NET, Python, TS\u002FJS, Java, Go, Ruby, Rust, Swift, Kotlin, PowerShell, C++. DO NOT USE FOR: writing new tests (use code-testing-agent \u002F writing-mstest-tests), mutation reasoning about whether tests would catch a bug (use test-gap-analysis), or a general severity-ranked anti-pattern audit (use test-anti-patterns), fixing or rewriting assertions, or writing, fixing, or modernizing MSTest tests, assertions, or attributes (use writing-mstest-tests).",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1281,1282,1285],{"name":20,"slug":21,"type":15},{"name":1283,"slug":1284,"type":15},"QA","qa",{"name":1173,"slug":1174,"type":15},"2026-07-12T08:23:51.277743",{"slug":1288,"name":1288,"fn":1289,"description":1290,"org":1291,"tags":1292,"stars":1239,"repoUrl":1240,"updatedAt":1306},"author-component","create and review Blazor components","Create or review Blazor components (.razor files) with correct architecture. USE FOR: writing new Blazor components that do NOT involve JavaScript interop, implementing parameters and EventCallback, RenderFragment slots, component lifecycle (OnInitializedAsync, OnParametersSet), async patterns, IAsyncDisposable, CancellationToken, CSS isolation, code-behind. DO NOT USE FOR: creating new projects (use create-blazor-project), JavaScript interop or calling browser APIs from Blazor (use use-js-interop), forms and validation (use collect-user-input), prerendering issues (use support-prerendering), HTTP data fetching patterns (use fetch-and-send-data), coordinating state between unrelated components (use coordinate-components).\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1293,1294,1297,1300,1303],{"name":13,"slug":14,"type":15},{"name":1295,"slug":1296,"type":15},"Blazor","blazor",{"name":1298,"slug":1299,"type":15},"C#","csharp",{"name":1301,"slug":1302,"type":15},"UI Components","ui-components",{"name":1304,"slug":1305,"type":15},"Web Development","web-development","2026-07-15T06:03:29.216359",{"slug":1308,"name":1308,"fn":1309,"description":1310,"org":1311,"tags":1312,"stars":1239,"repoUrl":1240,"updatedAt":1316},"binlog-failure-analysis","analyze MSBuild binary logs","Analyze MSBuild binary logs to diagnose build failures. USE FOR: build errors that are unclear from console output, diagnosing cascading failures across multi-project builds, tracing MSBuild target execution order, and generally any MSBuild build issues. Requires an existing .binlog file. DO NOT USE FOR: generating binlogs (use binlog-generation), non-MSBuild build systems.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1313,1314,1315],{"name":20,"slug":21,"type":15},{"name":23,"slug":24,"type":15},{"name":1254,"slug":1255,"type":15},"2026-07-12T08:21:34.637923",{"slug":1318,"name":1318,"fn":1319,"description":1320,"org":1321,"tags":1322,"stars":1239,"repoUrl":1240,"updatedAt":1328},"binlog-generation","generate MSBuild binary logs for diagnostics","Generate MSBuild binary logs (binlogs) for build diagnostics and analysis. USE FOR: adding \u002Fbl:{} to any dotnet build, test, pack, publish, or restore command to capture a full build execution trace, prerequisite for binlog-failure-analysis and build-perf-diagnostics skills, enabling post-build investigation of errors or performance. Requires MSBuild 17.8+ \u002F .NET 8 SDK+ for {} placeholder; PowerShell needs -bl:{{}}. DO NOT USE FOR: non-MSBuild build systems (npm, Maven, CMake), analyzing an existing binlog (use binlog-failure-analysis instead).",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1323,1326,1327],{"name":1324,"slug":1325,"type":15},"Build","build",{"name":23,"slug":24,"type":15},{"name":1184,"slug":1185,"type":15},"2026-07-19T05:38:19.340791",{"slug":1330,"name":1330,"fn":1331,"description":1332,"org":1333,"tags":1334,"stars":1239,"repoUrl":1240,"updatedAt":1338},"build-parallelism","optimize MSBuild build parallelism","Diagnose and fix under-parallelized MSBuild builds. USE WHEN a multi-project solution build is slower than expected, doesn't speed up when you add cores, pegs a single core while others idle, or you want to know why `-m` isn't helping. Note: `\u002Fmaxcpucount` default is 1 (sequential) — always pass `-m` for parallel builds. Covers finding the critical path (longest serial ProjectReference chain), graph build (`\u002Fgraph`), BuildInParallel, and solution filters (`.slnf`). DO NOT USE FOR: single-project builds, incremental issues (use incremental-build), compilation slowness inside one project (use build-perf-diagnostics), non-MSBuild build systems.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1335,1336,1337],{"name":13,"slug":14,"type":15},{"name":1184,"slug":1185,"type":15},{"name":1224,"slug":1225,"type":15},"2026-07-19T05:38:18.364937",{"slug":1340,"name":1340,"fn":1341,"description":1342,"org":1343,"tags":1344,"stars":1239,"repoUrl":1240,"updatedAt":1351},"build-perf-baseline","establish and optimize build performance baselines","Establish build performance baselines and apply systematic optimization techniques. USE FOR: diagnosing slow builds, establishing before\u002Fafter measurements (cold, warm, no-op scenarios), applying optimization strategies like MSBuild Server, static graph builds, artifacts output, and dependency graph trimming. Start here before diving into build-perf-diagnostics, incremental-build, or build-parallelism. DO NOT USE FOR: non-MSBuild build systems, detailed bottleneck analysis (use build-perf-diagnostics after baselining).",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1345,1346,1349,1350],{"name":1184,"slug":1185,"type":15},{"name":1347,"slug":1348,"type":15},"Monitoring","monitoring",{"name":1224,"slug":1225,"type":15},{"name":1173,"slug":1174,"type":15},"2026-07-12T08:21:35.865649",{"slug":1353,"name":1353,"fn":1354,"description":1355,"org":1356,"tags":1357,"stars":1239,"repoUrl":1240,"updatedAt":1362},"build-perf-diagnostics","diagnose MSBuild build performance bottlenecks","Diagnose MSBuild build performance bottlenecks using binary log analysis. USE FOR: identifying why builds are slow by analyzing binlog performance summaries, detecting ResolveAssemblyReference (RAR) taking >5s, Roslyn analyzers consuming >30% of Csc time, single targets dominating >50% of build time, node utilization below 80%, excessive Copy tasks, NuGet restore running every build. Covers timeline analysis, Target\u002FTask Performance Summary interpretation, and 7 common bottleneck categories. Use after build-perf-baseline has established measurements. DO NOT USE FOR: establishing initial baselines (use build-perf-baseline first), fixing incremental build issues (use incremental-build), parallelism tuning (use build-parallelism), non-MSBuild build systems.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1358,1359,1360,1361],{"name":13,"slug":14,"type":15},{"name":23,"slug":24,"type":15},{"name":1184,"slug":1185,"type":15},{"name":1224,"slug":1225,"type":15},"2026-07-12T08:21:40.961722",{"slug":1364,"name":1364,"fn":1365,"description":1366,"org":1367,"tags":1368,"stars":1239,"repoUrl":1240,"updatedAt":1372},"check-bin-obj-clash","detect MSBuild output path conflicts","Detects MSBuild projects with conflicting OutputPath or IntermediateOutputPath. USE FOR: builds failing with 'Cannot create a file when that file already exists', 'The process cannot access the file because it is being used by another process', intermittent build failures that succeed on retry, or missing\u002Foverwritten outputs in multi-project or multi-targeting builds where bin\u002Fobj (or project.assets.json) collide. Common causes: shared OutputPath, missing AppendTargetFrameworkToOutputPath, extra global properties (e.g. PublishReadyToRun), or SetTargetFramework on a ProjectReference to a single-targeting project. DO NOT USE FOR: file access errors unrelated to MSBuild (OS-level locking), single-project single-TFM builds, non-MSBuild build systems.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[1369,1370,1371],{"name":23,"slug":24,"type":15},{"name":1184,"slug":1185,"type":15},{"name":1283,"slug":1284,"type":15},"2026-07-19T05:38:14.336279",144]