Binlog Generation

What it does

When your agent uses it

• : adding /bl:{} to any dotnet build
• 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

Example prompts

• “/binlog-generation”

Workflow steps

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

1. 1Unique names prevent overwrites - You can always go back and analyze previous builds
2. 2Failure analysis - When a build fails, the binlog is already there for immediate analysis
3. 3Comparison - You can compare builds before and after changes
4. 4No re-running builds - You never need to re-run a failed build just to generate a binlog

What it can do on your machine

Read from SKILL.md and the folder at commit 44b9dcc. 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

  Shell commands in SKILL.md call:

  • dotnet
  • git

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

• Network

  No URLs in SKILL.md. Its commands use git, which can reach the network depending on how they are called.

  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

Binlog Generation loads about 824 tokens when it runs. Until then it costs about 142 tokens; SKILL.md has 266 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~142

When it runs · the whole SKILL.md, loaded when a task matches

~824

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

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 microsoft/testfx at commit 44b9dcc, republished under its MIT licence (© microsoft). 266 words, ~824 tokens.

name

binlog-generation

description

Generate MSBuild binary logs (binlogs) for build diagnostics and analysis. USE FOR: adding /bl:{} 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+ / .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).

license

MIT

# Every invocation produces a distinct file automatically
dotnet build /bl:{}
dotnet test /bl:{}
dotnet build --configuration Release /bl:{}

# PowerShell: escape { } as {{ }}
dotnet build -bl:{{}}
dotnet test -bl:{{}}

# ✅ CORRECT - {} generates a unique name automatically (bash/cmd)
dotnet build /bl:{}
dotnet test /bl:{}

# ✅ CORRECT - PowerShell escaping
dotnet build -bl:{{}}
dotnet test -bl:{{}}

# ❌ WRONG - Missing /bl flag entirely
dotnet build
dotnet test

# ❌ WRONG - No filename (overwrites the same msbuild.binlog every time)
dotnet build /bl
dotnet build /bl

# Example: directory contains 3.binlog — use 4.binlog
dotnet build /bl:4.binlog

# ✅ CORRECT - Exclude binlog files from cleaning
git clean -fdx -e "*.binlog"

# ❌ WRONG - This deletes binlog files (they're usually in .gitignore)
git clean -fdx

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

Files

Just SKILL.md in .agents/skills/binlog-generation of microsoft/testfx.

Open the folder on GitHubat commit 44b9dcc

Used in 2 other repositories

We found 3 copies of this SKILL.md (exact, near-identical or edited) in other folders, from 2 other GitHub owners. This page covers the copy in microsoft/testfx, which our catalogue first saw on October 7, 2026.

• dotnet/skillsplugins/dotnet-msbuild/skills/binlog-generation
• managedcode/dotnet-skillscatalog/Tools/Official-DotNet-MSBuild/skills/binlog-generationexternal-sources/upstreams/dotnet-skills/plugins/dotnet-msbuild/skills/binlog-generation