Grok Build Agent Skill

Grok Build Orchestration

The coding assistant is the orchestrator: it plans, writes self-contained task specs,

dispatches them to Grok Build headlessly, reviews every diff, and owns the final result.

Grok is the fast, cheap executor. Full CLI details and verified behaviors: references/cli.md.

When to delegate vs keep with the orchestrator

| Delegate to Grok | Keep with the orchestrator |

|---|---|

| Plan tasks with clear acceptance criteria | Ambiguous requirements, architecture decisions |

| Boilerplate, scaffolding, CRUD | Deep cross-file debugging |

| Mechanical refactors | Security-sensitive code |

| Test writing from clear specs | Anything touching production infrastructure |

| UI components from mockups/specs | Tasks where writing the spec ≈ doing the work |

When in doubt, keep it with the orchestrator.

Session preflight (once, before the first dispatch)

• grok update --check --json — if updateAvailable is true, run grok update and

confirm with grok --version.

• grok models — if it errors or reports logged out, STOP and ask the user to run

grok login.

Per-task loop (sequential — the default)

• Spec. Write a self-contained task file (template below) to a temp directory

OUTSIDE the target repo — the harness scratchpad if one is available, else the OS

temp dir. Never write it inside the target repo. Grok has zero conversation context:

no one-liner prompts, ever.

• POSIX: mkdir -p "${TMPDIR:-/tmp}/grok-specs", then write task.md there.
• Windows (PowerShell): New-Item -ItemType Directory -Force "$env:TEMP\grok-specs",

then write task.md there.

• Clean state. No uncommitted *source* changes — commit or stash first, so the

post-run diff is exactly Grok's work. Ignore build artifacts (__pycache__, dist/,

etc.); if they show in git status, they're usually just un-gitignored, not your

concern. Never dispatch on a dirty source tree.

• Dispatch.

POSIX:

   grok --prompt-file <task-file> \
     --output-format json \
     --always-approve \
     --max-turns 30 \
     --cwd <repo>

Windows (PowerShell) — backtick line-continuation:

   grok --prompt-file <task-file> `
     --output-format json `
     --always-approve `
     --max-turns 30 `
     --cwd <repo>

Parse the JSON output and save sessionId. (--always-approve is required for

headless runs — --permission-mode acceptEdits silently cancels edits with no

interactive approver. See references/cli.md.) For a high-stakes task, add --check

so Grok self-verifies before you review; skip it otherwise (it ~doubles latency).

• Review gate — non-negotiable.
• Read the diff yourself (git diff -- <files from the spec> to skip artifact noise):

does it do the task, only the task, and match repo conventions?

• Run the acceptance commands from the spec.
• Pass → commit with a clear message following the repo's convention → next task.
• Fail → fix-up: `grok --resume <sessionId> -p "<specific feedback>"

--always-approve --output-format json`. Max 2 fix-up rounds. Still failing →

revert Grok's changes (git checkout -- .; git clean -fd for new files), do the

task yourself, and tell the user Grok couldn't complete it.

Task spec template

# Task: <one-line title>

## Context
- Repo: <path> — <one line on what the project is>
- Conventions: <test runner, formatter, a good example file to imitate>

## Files
- Modify: <path>
- Create: <path>

## Task
<precise description of the change>

## Constraints
- Do not modify any files other than those listed above.
- <other constraints>

## Acceptance criteria
- `<exact command>` <expected result>

Executing a Markdown implementation plan

• One plan task per dispatch, in order.
• Check off the plan's task checkboxes (- [ ] → - [x]) as each task lands and passes

the review gate.

• If the plan explicitly marks tasks as independent, see Parallel dispatch below;

otherwise stay sequential.

Parallel dispatch (opt-in exception, not the default)

Only when a plan explicitly marks tasks independent: dispatch each with

--worktree=<task-slug>, run concurrently, then review and merge one worktree at a

time through the same review gate. Merge conflicts usually eat the savings — prefer

sequential.

Failure handling

| Failure | Action |

|---|---|

| stopReason: "Cancelled", empty text, no diff | Missing --always-approve — retry with it |

| CLI error / timeout | Retry once; then do the task yourself and note the fallback |

| Auth expired | Stop; ask the user to run grok login |

| 2 fix-up rounds exhausted | Revert Grok's diff; the orchestrator finishes the task |

| Dirty tree at dispatch | Refuse; commit/stash first |

Models

Default grok-4.5. Add -m grok-composer-2.5-fast only for trivial mechanical tasks.