Script Builder

script-builder

You are converting session intent into a durable, re-runnable script committed to the target project's scripts/ directory. Two script classes share one principle — only the derived answer re-enters context; raw payloads never do:

• Validation scripts (check-*, e2e-*, smoke-*, …): a single PASS/FAIL line + /tmp log path on success, full verbose output redirected to a timestamped log file.
• Gather/bulk scripts (gather-*, bulk-*): replace N similar tool/API calls with one script that loops, filters, and aggregates in code — stdout is one compact summary block (JSON or table), raw responses go to the /tmp log. Rubric (from production code-mode data): past ~10 items or any fan-out over a list, a script beats individual tool calls by ~100x on context and roughly halves end-to-end cost. Offer the script before the fan-out happens when you can see it coming, not just retrospectively.

Both classes get an <important if> block in CLAUDE.md/AGENTS.md so future agents discover the script when the intent recurs — durable scripts are reusable agent memory: import, don't re-derive.

Schema discovery happens in code, too: when scripting against an unfamiliar API, grep/filter its OpenAPI spec or typed client programmatically to find the few relevant endpoints — never paste the full schema into context.

Working Agreement

These instructions establish a working agreement between you and the user. The key principles are:

1. AskUserQuestion is your primary communication tool - Whenever you need to ask the user anything (clarifications, preferences, decisions, confirmations), use the AskUserQuestion tool. Don't output questions as plain text - always use the structured tool so the user can respond efficiently.

2. Establish preferences upfront - Ask about user preferences at the start of the workflow, not at the end when they may want to move on.

3. Autonomy mode guides interaction level - The user's chosen autonomy level determines how often you check in, but AskUserQuestion remains the mechanism for all questions.

When to Use

This skill activates when:

• User invokes /script-builder command
• Another skill references **OPTIONAL SUB-SKILL:** desplega:script-builder
• A planning, qa, or verifying flow needs a re-runnable validation script that doesn't yet exist
• The user expresses intent to "turn X into a script", "wrap this validation into something reusable", or "I want to test X end-to-end" with no existing script

Autonomy Mode

Adapt your behavior based on the autonomy mode:

The autonomy mode is passed by the invoking command. If not specified, default to Critical.

Process Steps

Step 1: Detect Mode (Retrospective vs Forward-Declared)

Decide silently — do not ask the user "which mode?". Use the following heuristics:

1. Scan recent session tool-use history (the last ~20 tool calls in the current conversation) for test/validation-shaped activity: curl/fetch calls, bun run/python/pytest, database queries, agent-browser actions, repeated grep/log inspection of a single endpoint or table. If ≥2 such actions targeting the same area exist → retrospective mode. Separately, if the history (or the task ahead) shows the same call shape repeated ~10+ times or a fan-out over a list → gather-script mode: propose replacing the repetition with one gather-* script before continuing.
2. Parse the user's invocation message for cues:
   • Narrative cues → retrospective: "we just figured out", "turn this into a script", "wrap that in", "that thing we just did".
   • Intent cues → forward-declared: "I want to test", "validate that", "smoke check", "check before deploy".
3. Fallback: when ambiguous, default to forward-declared.

Retrospective first action: summarize the observed activity back to the user as plain text (≤6 lines: what was probed, against what, with what success signal), then go to Step 3 with a confirmation prompt instead of Q&A.

Forward first action: skip directly to Step 3's Q&A.

Step 2: Scan Existing Scripts for Overlap

Resolve the scripts directory in this order:

1. Check CLAUDE.md for a <!-- script-builder:dir=<path> --> marker. If present, use that path.
2. If scripts/ exists at the repo root, use it.
3. Use AskUserQuestion with options: scripts/ (Recommended) | custom path | skip dir persistence for this run.

Edge case — directory absent: if the resolved path doesn't exist, skip the dedup scan, print a one-line note (No existing scripts directory at <path> — proceeding to intent gathering), and remember to optionally offer to create the directory before Step 5.

When the directory exists:

1. List files in the scripts directory (top-level only for v1).
2. For each file, read the top of the file (header comment) and capture the file-name tokens.
3. Read CLAUDE.md/AGENTS.md for <important if="..."> blocks that point at scripts in this directory and capture the trigger phrases.
4. Fuzzy-match the current intent string against (file-name tokens ∪ header keywords ∪ trigger phrases). A "plausible match" is shared keyword + same area noun (e.g., auth, health, webhook).
5. If ≥1 plausible match → use AskUserQuestion with options: Reuse <name> as-is | Extend <name> | Generate new anyway.

Never silently skip dedup on borderline matches — surface and let the user decide. The Extend branch appends a sub-command/flag to the existing script (do not create a new file); document the new flag in the script's header comment and the existing <important if> block.

Step 3: Gather Intent

Both modes converge on the same internal intent structure: { what, success_signal, failure_signal, inputs, env, side_effects }.

Forward mode — use AskUserQuestion (one or two questions, not five):

Retrospective mode — present the summary from Step 1 and use AskUserQuestion with: That's the flow | Close but fix X | Start over. On Close but fix X, ask for the correction inline; on Start over, fall through to forward-mode Q&A.

Persist the resolved intent in working memory (do not write to disk yet).

Step 4: Detect Language

Priority order — first match wins, with override paths:

1. TypeScript — package.json + tsconfig.json exist.
   • Bun if bun.lock or bunfig.toml is present.
   • else tsx if tsx appears in package.json devDependencies.
   • else compiled Node (note in script header: requires tsc build).
2. Python — pyproject.toml or uv.lock or requirements.txt exists.
   • uv if uv.lock exists or pyproject.toml has [tool.uv] configured (sets {{UV_METADATA}}).
   • else vanilla python3 ({{UV_METADATA}} substituted with empty string).
3. Both TS and Python detected — count source files in src//top-level and ask AskUserQuestion tiebreaker with the dominant one Recommended.
4. Cargo.toml / go.mod only → fall back to bash (note: TS/Python/Bash only in v1).
5. Nothing matched → bash.

Task-driven override: if the gathered intent is clearly shell-y ("verify three docker containers respond", "tail this log file for an error"), propose bash even in a TS/Python project.

Confirm via AskUserQuestion with the detected language as the first option (Recommended). Skip in Autopilot.

Step 5: Draft the Script

1. Pick the template: cc-plugin/base/skills/script-builder/templates/{typescript.ts.tmpl|python.py.tmpl|bash.sh.tmpl}.
2. Resolve substitution markers from gathered intent:
   • {{SCRIPT_NAME}} ← proposed file-name stem (see naming table).
   • {{WHAT}} / {{WHEN}} / {{ENV}} / {{EXAMPLE}} ← intent fields.
   • {{UV_METADATA}} ← per Step 4.
3. Generate {{TEST_BODY}} from the intent. Keep it minimal: a single concrete probe + assertion, not a battery. Re-read the templates' README (templates/README.md) for the contract — the body must respect the PASS/FAIL surface. Throw/raise/exit 1 on failure; let the template's outer try/trap convert it into the FAIL line. Gather-class bodies adapt the same template: the loop/aggregation replaces the probe, raw per-item responses go to the log only, and the final console.log/print emits one compact summary (JSON or aligned table) instead of the PASS line — exit non-zero only on operational failure (auth, network), not on "found problems" (problems ARE the output).
4. Propose a file name matching the intent shape — see the prefix table below. Use AskUserQuestion with the proposed name first (Recommended) and custom name as the alternative.

Naming conventions (advisory — skill proposes, user overrides):

If the intent doesn't match any prefix cleanly, propose a free-form name like validate-<area>.<ext>.

5. Write the file to the resolved scripts directory. Make it executable (chmod +x).

Step 6: Syntax/Type-Check

Run the appropriate checker:

On success: log a single line (syntax check OK) and proceed to Step 7.

On failure:

1. Print the error (≤10 lines, not the full output).
2. Propose a concrete one-edit fix (the exact Edit you'd apply).
3. Use AskUserQuestion with Apply fix | Investigate | Stop.
   • Apply fix → edit the script and re-run the checker (loop, no hardcoded cap).
   • Investigate → drop into discussion with the user; do not auto-apply anything.
   • Stop → leave script in place at its path; print the path; do not delete.

Step 7: Document the Script

Auto-edit the target project's CLAUDE.md and/or AGENTS.md so future agents discover this script when the matching intent recurs.

Block template (the literal markdown the skill emits):

<important if="[TRIGGER: e.g., you are testing the auth flow]">

## [Area] validation

Run `scripts/<name>` to [one-liner]. Requires [env/deps]. Example: `<cmd>`. Full log at `/tmp/<name>-*.log`.

Generated/maintained via `/script-builder`.

</important>

Behavior:

1. Target file selection: edit CLAUDE.md and AGENTS.md if both exist; edit only what exists. Never create either file from scratch — if neither exists, print a one-line note (No CLAUDE.md or AGENTS.md found — script generated but not documented) and skip this step.
2. Placement heuristic: search the file for the first heading matching Test|Testing|Validation|Scripts (case-insensitive). If found, append the new block within/after that section. Otherwise, append a new ## Scripts for testing & validation section near the end of the file but before any heading matching License|Acknowledg|Maintain|Contributors.
3. Idempotency: if a block referencing scripts/<name> already exists (i.e., a prior /script-builder run for the same script name), update it in place — replace the entire <important if=...>...</important> block, do not append a duplicate.
4. Scripts-dir marker: if Step 2 resolved the scripts directory by user choice (not from an existing marker), insert <!-- script-builder:dir=<path> --> near the top of CLAUDE.md (after the title) so subsequent runs are silent. Skip if the marker already exists.
5. Scale gate — scripts/index.md: if the scripts directory holds >10 documented scripts, per-script <important if> blocks become their own context bloat. Generate/maintain a scripts/index.md hub instead (one line + link per script, mirroring the runbooks/ convention from desplega:engineering-standards), collapse the CLAUDE.md/AGENTS.md blocks into ONE pointer block referencing the hub, and add new scripts to the hub only.
6. Show the diff: run the equivalent of git diff CLAUDE.md AGENTS.md and print a 5-line summary of what changed. Never auto-stage — the user commits.

Step 8: Offer Escalation

After the doc edit, decide whether to proceed to the run-and-iterate tier.

If the user picks "I'll run it myself later" or "Just generate, don't run" → skip directly to Step 10.

Step 9: Iterate on Failures (Escalated Tier Only)

A bounded-by-the-human loop. Never auto-apply a fix outside Autopilot.

1. Run the script with the proposed example invocation (no --verbose, no --json). Capture exit code and tail -n 40 of the /tmp log.
2. If exit code 0 → report PASS (echo the script's PASS line) and proceed to Step 10.
3. If exit code non-zero:
   • Summarize the failure in 1–3 lines: error class (timeout / 4xx / 5xx / assertion / dependency-missing / etc.) + likely cause (grep the log for known signatures: ECONNREFUSED, Traceback, non-zero exit, command not found, etc.).
   • Propose a concrete diff — the exact Edit you would apply to the script. Show old → new.
   • Use AskUserQuestion: Apply fix | Investigate differently | Stop.
     • Apply fix → edit the script, log the change, loop back to (1).
     • Investigate differently → drop into discussion; do not auto-apply.
     • Stop → leave the script in place, print its path; do not revert.

No hardcoded retry cap — the human is the implicit bound.

Side-effect flag: if the intent declared side-effects (Step 3) and Autopilot is active, surface a one-line WARNING: this script <does X> against <target> before the first run and require explicit confirmation via AskUserQuestion even in Autopilot mode.

Step 10: Handoff

How the skill exits depends on how it was invoked:

Invoked as a sub-skill (from planning, qa, verifying): Return control to the parent skill with a structured summary: { script_path, status: "pass"|"fail"|"unrun", log_path?, doc_files_edited: [...] }.

Invoked directly (/script-builder): Use AskUserQuestion: Run it with /qa | Run /verify-plan | Commit the script and doc changes | Done.

• Run with /qa → invoke desplega:qa with the script path as the source.
• Run /verify-plan → invoke desplega:verifying if a plan path is in current context.
• Commit → propose a commit message (feat(scripts): add scripts/<name> for <area> validation) and stage only the generated script + the CLAUDE.md/AGENTS.md edits. Do not auto-commit; show the proposed git add and git commit commands and require user confirmation.
• Done → print the script path + log path (if escalation ran) and exit.

Abort path (Stop selected at any earlier gate): leave the generated script in place, leave any CLAUDE.md/AGENTS.md edit in place if Step 7 ran, and print a one-liner: Aborted. Script: <path>. Doc edits: <files or "none">. Re-run /script-builder or git checkout to discard. Do not git restore on the user's behalf.

Learning Capture

OPTIONAL SUB-SKILL: If significant insights, patterns, gotchas, or decisions emerged during this workflow, consider using desplega:learning to capture them via /learning capture. Focus on learnings that would help someone else in a future session.