Execute and supervise external programs safely from Go CLIs with explicit arguments, typed failure classification, working directories, environments, bounded streams, deadlock-safe pipes, contexts, timeouts, signals, platform adapters, descendant cleanup, runner seams, and lifecycle tests.
SkillScore96Maintained
Automatic
◆Coding pack
Last verified 8/16/2026
What it changes
Passed 25 of 26 test cases with the skill, and 23 of 26 without it.
Without skill88%
With skill96%
Checks it passed that the model alone missed
The implementation must call Wait on every process started in the pipeline.
The response must state that cmd.String is intended only for diagnostic logging.
The implementation must call Wait after Start to verify process execution outcome.
3 fixed22 passed either way0 still failing1 broke
Pass-rate lift
+8 pp
Tokens
+17%
Agent turns
0%
Response time
-14%
Model gemini-3.6-flashMeasured 8/16/2026v125 of 26 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 3 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 3
Prompt
We are writing a CLI tool in Go that pipes the output of an archive tool directly into an encryption binary. We need a function to manage this subprocess pipeline reliably, ensuring pipes are properly closed, all pipeline processes are waited on, and failures are clearly reported. Please provide the Go implementation for this pipeline manager.
What was checked, without and with the skill
Checked
Without skill
With skill
The implementation must call Wait on every process started in the pipeline.
Missed
Passed
The implementation must close pipe resources on process start failure.
Passed
Passed
case-01 · gemini-3.6-flash · 8/16/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md55 linessingle file
Go CLI Process Control
Treat child-process lifecycle as correctness. Observe the terminal result,
propagate cancellation, and clean up every process, pipe, and temporary resource.
Core Workflow
Define the child executable, argv, environment, directory, streams, and success contract.
Use an explicit shell only when shell semantics are actually required.
Inject a runner boundary and propagate the caller's context.
Observe startup and completion; preserve status and useful redacted stderr.
Bound captured output, cancellation, and shutdown time.
Account for descendants and wait for every pipeline stage.
Test missing tools, bad exits, malformed output, cancellation, signals, and cleanup.
Design and review adaptive Go CLI terminal experiences with explicit human, plain, and structured modes; per-stream TTY detection; color and accessibility controls; prompts; progress; secret input; cancellation; and broken-pipe handling. Use when a Go CLI must work safely for people, scripts, AI agents, CI, redirected streams, or interactive dashboards.