Make sample 318 stdin-runnable for the daily Rig sampler

[Copilot]

The daily Rig sample report failed on 318-ts-barrel-re-exporter.md because the exported root agent required structured input, while markdown samples are executed through the stdin launcher and must expose an input-free root. This updates the sample to match the launcher contract without changing runtime behavior.

• Root contract

  • Removed required root input from 318-ts-barrel-re-exporter.md
  • Kept the sample as a single exported agent so it remains runnable by the sampler and launcher

• Sample behavior

  • Scoped the sample to a concrete target: skills/rig/engines
  • Switched file emission from p.writeInput(...) to a fixed temp path via p.writeOutput(...)
  • Added barrelContent to the declared output so the generated barrel is both returned and written

• Sample shape

  • Preserved the barrel re-export example and export-symbol extraction tool
  • Kept the sample within the markdown sample constraints, including the required role annotation and compact code size

const tsBarrelReExporter = agent({
  model: "small",
  instructions: p`Generate a TypeScript barrel for skills/rig/engines ... ${p.writeOutput("barrelContent", "/tmp/rig-barrel.ts")}`,
  output: s.object({
    barrelContent: s.string,
    exports: s.array(s.string),
    outputFile: s.path,
    totalExports: s.int,
    filesScanned: s.int,
  }),
});

• Fixes [rig-sampler] Daily Rig sample report — 2026-07-30 #301

[github-actions]

🧠 Matt Pocock Skills Reviewer has completed the skills-based review. ✅

[github-actions]

Skills-Based Review 🧠

Applied /codebase-design — no blocking issues, but two readability suggestions.

📋 Key Themes & Highlights

Key Themes

• Readability regression: the instructions, tool definition, and output schema were compressed into one-liners. For a sample file that exists to teach, this is a net negative — multi-line form is the convention throughout the rest of the sample directory.
• Root contract fix is correct: removing input and switching to p.writeOutput with a fixed temp path is exactly the right way to satisfy the stdin-launcher contract.

Positive Highlights

• ✅ Root cause correctly identified and fixed (input-free root required by stdin launcher)
• ✅ barrelContent added to output so the generated barrel is both returned and written
• ✅ p.writeInput → p.writeOutput switch is semantically accurate
• ✅ repair() addon retained

Not Addressed (out of scope, but worth noting)

• No regression test guards against the sampler failure recurring — this is an existing gap in the test suite, not introduced by this PR.

🧠 Reviewed using Matt Pocock's skills by Matt Pocock Skills Reviewer · sonnet46 29.5 AIC · ⌖ 4.28 AIC · ⊞ 6.3K
_{Comment /matt to run again}

[github-actions]

[/codebase-design] The instructions are now a single dense line, sacrificing the readability that made the original multi-line template literal easy to scan.

💡 Suggested refactor

Split the template literal across lines:

instructions: p`Generate a TypeScript barrel for skills/rig/engines
from ${p.bash("find skills/rig/engines -name '*.ts' -not -name 'index.ts' -not -name '*.d.ts' | head -20")}.
Use extractExportedSymbols for each file, set outputFile to /tmp/rig-barrel.ts,
write barrelContent to ${p.writeOutput("barrelContent", "/tmp/rig-barrel.ts")},
and return the declared output.`,

This matches the style of other samples and keeps each prompt step scannable at a glance.

[github-actions]

[/codebase-design] The tool definition and output schema are now one-liners, which keeps file size down but harms readability in a sample whose purpose is to teach. Samples are documentation first.

💡 Suggested refactor

Expand the output schema and tool definition to multi-line form, consistent with every other sample in the directory:

  output: s.object({
    barrelContent: s.string,
    exports: s.array(s.string),
    outputFile: s.path,
    totalExports: s.int,
    filesScanned: s.int,
  }),

Similarly, break the tool handler body out of the one-liner .flatMap chain for legibility.