codex-delegate git:20261015.8ae5a79A

Immutable. This exact content never changes and is served at /api/v1/blob/b8114c19143865cb.

---
name: codex-delegate
description: Delegate implementation, investigation, or bulk work to gpt-6 codex via pinned codex exec. Use for clear-spec builds, migrations, debugging, or any task the routing table below sends to codex.
---

# Codex Delegate

Hand a task to the gpt-6 family through the Codex CLI. This is the delegation
path: the main loop (Root) invokes Codex **directly through Bash -
no Claude shim, and never a Claude worker whose only job is to launch, wait for,
or relay a Codex call**.

## Delegation gate (check before delegating at all)

Delegate only when at least one shape applies: `independence` (fresh-eyes or
adversarial value), `context` (repo/research mass stays out of the root
context), `contract` (clear-spec implementation with a written contract,
roughly >=2h), or `parallel` (independent taste-free lanes save wall-clock).
Otherwise Root works inline. Cap concurrent model lanes at 2-3.

Never route design/UI/copy/naming/API-ergonomics or final architecture
decisions to codex.

## Model + effort routing (always pin BOTH `-m` and effort - never inherit defaults)

| lane | pin | use |
|---|---|---|
| **default** | **`gpt-6-sol` + `"max"`** | almost everything: implementation, debugging, code review, retrieval, repo mapping, inventories, dependency tracing, bounded analysis and synthesis |
| fast | `gpt-6-luna` + `"high"` | latency-sensitive work: exploration, file and symbol location, shallow inventories, a quick second read - anywhere a fast good answer beats a slow better one |
| maximum intelligence | `gpt-6-astra` + `"max"` | one independent adversarial check or alternate solution, and the rare task the default lane cannot carry |
| last resort | `gpt-6-astra` + `"max"` | rare and root-gated |

Re-check current provider pricing before treating cost as a routing reason; never inherit model/effort silently, always pin -m and effort explicitly per call.

The gap is **traversal depth, not polish**: the fast lane never entered
`node_modules`, so it missed everything that depended on what an installed
dependency actually does — including a high-confidence defect. Treat `high` as a
genuinely shallower read, not a cheaper version of the same read. Use it for
exploration and location, where a fast partial answer is the point, and `max`
for depth-sensitive work where the answer turns on what a dependency or a
distant file actually does.

Effort is a depth signal, not a completeness guarantee. Nothing about a
reasoning tier establishes that the scope was covered or the claims verified -
only explicit scope, coverage, and verification evidence does that. Do not
report a `max` lane as complete merely because it ran at `max`.

Escalation ladder: **gpt-6-luna high → gpt-6-sol max → gpt-6-astra max → Root finishes the hard
part inline** (or an Opus high worker when a delegation shape holds). Astra max
requires one of: critical blast radius with no cheap deterministic oracle;
unresolved disagreement after gpt-6-sol max and gpt-6-astra max; two failed strong
attempts. Only one active Astra max call.

Bans: **no gpt-6-astra xhigh or ultra; no gpt-6-astra effort other than max; never
mini/spark-class models.**

Consequential or cross-cutting implementation still routes to Opus high workers
or Root inline; Codex is the independent second opinion there, or
the primary when Claude quota is the binding constraint.

## Composing the prompt

Codex sees NONE of the Claude conversation - prompts must be fully
self-contained: objective and expected deliverable, exact scope/files and
ownership, relevant context and constraints, permitted edits and sandbox,
required checks, output format and completion criteria. For structured
returns, pass `--output-schema <schema.json>`.

## Invocation

```bash
# Investigation / retrieval (read-only, default lane)
codex exec -C "<repo>" -m gpt-6-sol -c model_reasoning_effort="max" --sandbox read-only --output-last-message "<scratchpad>/codex-out-<ts>.md" "<self-contained prompt>"

# Fast exploration (read-only) - trade depth for latency
codex exec -C "<repo>" -m gpt-6-luna -c model_reasoning_effort="high" --sandbox read-only --output-last-message "<scratchpad>/codex-out-<ts>.md" "<self-contained prompt>"

# Implementation (write-capable) - ALWAYS pass the sandbox
# explicitly; never inherit the config default (danger-full-access)
codex exec -C "<repo>" -m gpt-6-sol -c model_reasoning_effort="max" --sandbox workspace-write --output-last-message "<scratchpad>/codex-out-<ts>.md" "<self-contained prompt>"
```

Rules:
- ONE bare command per call - no pipes, no `cd &&` chains (keeps the RTK hook inert).
- Outside a git repository, add `--skip-git-repo-check` (codex exec errors there otherwise).
- Short blocking calls: foreground Bash. Long or parallel calls: Bash
  `run_in_background: true`; read the result file when the harness notifies  - 
  inspect logs only on failure or empty output. Never attach a Monitor just to
  detect completion.
- Use isolated worktrees when parallel writers could overlap; one owner per
  file/domain.
- Follow-ups continue the same Codex session:
  `codex exec resume --last "<follow-up instruction>"`. Sessions are looked up
  from the working directory, so run this from the same cwd/repo scope as the
  original call (or pass the recorded session id instead of `--last`).

## Closing the loop

Delegated output is provisional until Root closes it:
1. `git diff` - review what Codex actually changed before accepting it.
2. Run the relevant deterministic checks (tests / type-check / lint / build) and
   iterate until green.
3. If Codex went beyond the delegated scope, revert the extra scope and
   re-delegate with tighter constraints.

If output misses the bar, escalate up the ladder (or redo on opus-5/Root
inline) without asking - judge the output, not the price.