Scans the project root for config files (mix.exs, package.json, Cargo.toml, go.mod, Makefile), runs the appropriate build command, captures output, and reports errors with structured diagnostics. Handles monorepos by detecting and building each sub-project.
SkillScore70Maintained
Automatic
◆Coding pack
Last verified 8/27/2026
What it changes
Passed 13 of 19 test cases with the skill, and 7 of 19 without it.
Without skill39%
With skill70%
Checks it passed that the model alone missed
Invokes /build
Invokes /build backend/api
Executes the project test suite
and 5 more in the full report
8 fixed8 passed either way6 still failing1 broke
Pass-rate lift
+30 pp
Tokens
-23%
Agent turns
0%
Response time
-34%
Model gemini-3.6-flashMeasured 8/27/2026v316 of 23 cases passed with skill · 19 comparable
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 8 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 8
Prompt
I want to compile the root project repository without running tests or cleaning existing artifacts. What command executes this compilation pipeline?
What was checked, without and with the skill
Checked
Without skill
With skill
Invokes /build
Missed
Passed
case-04 · gemini-3.6-flash · 8/27/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md26 linessingle file
/build
Build, compile, and test. Engineer-owned.
Usage
/build [path] [--clean] [--test] [--verbose]
What It Does
Detects project type, runs the build pipeline, captures errors, and reports results
with structured diagnostics. Optionally runs tests after build.
Implementation
Detect — Identify project type from config files.
Clean — Remove build artifacts if --clean.
Build — Run build command, capture stdout/stderr/exit code.
Test — Run test suite if --test.
Report — Structured build report with errors, warnings, artifacts.