Arbitrage

Arbitrage

Fable tokens are expensive; the user's codex quota sits unused. Exploit the price gap: spend Fable tokens on judgment — planning, specs, design intent, visual validation — and spend codex quota on all code-writing volume.

You ARE the Fable session. "Here" means you do it yourself. There is no separate Fable to delegate to.

Routing Table

| Work | Where | Why | |------|-------|-----| | Planning, specs, architecture decisions | Here | Judgment is what Fable is paid for | | ALL implementation — backend, frontend, anything that writes code | codex via /goal | Quota is free; typing code is not where Fable adds value | | Visual validation of UI work (run the app, screenshot, judge, iterate) | Here | Fable's design eye is worth the price — validate, don't type | | Investigation and debugging analysis (root-causing hard bugs) | Here | Judgment work; the resulting fix dispatches with a precise spec | | Diff review, commits, pushes, PRs | Here | Git operations stay under your control | | Trivial edits riding along with review/validation (one-liners, any layer) | Here | Dispatch overhead exceeds the work | | Work codex has demonstrably struggled with | Here | Escape hatch — see below |

Dispatch Protocol

1. Spec first. Write a spec file in the worktree: objective, constraints, files/areas involved, acceptance criteria — the exact test command that must go green — and what NOT to touch. For frontend work the spec carries the design intent: layout, states, interactions, spacing, motion, reference patterns. For the hardest parts, spec down to pseudocode — the thinking stays here; the typing still dispatches.
2. Dispatch in the background and keep working:

``bash codex exec --cd "/goal " `` codex runs gpt-5.5 with xhigh reasoning (its default config); it implements and gets tests green in the isolated worktree while you continue planning/spec/validation work in parallel.

1. Review the diff here. Commit, push, and open PRs from this session.

Visual Validation Loop (frontend)

1. codex implements the UI per spec.
2. Run the app here — interact, screenshot, judge against the design intent.
3. Write concrete visual feedback (what's off, by how much, what good looks like) and re-dispatch.
4. Loop until it looks right; then diff review + git here.

Escape Hatch: When codex Struggles

Struggle must be observed, not predicted. Always dispatch first — predicting "codex can't do this" just means the spec needs pseudocode-level detail. But two strikes and it's yours: if a re-dispatch with concrete corrective feedback still comes back missing the acceptance criteria or mangling the approach, stop re-dispatching and write the code here yourself, salvaging whatever of codex's diff is sound.

Red Flags

| Thought | Reality | |---------|---------| | "Frontend is design-critical, so I'll code it here" | Fable's taste shows up in the spec and the validation loop, not in typing JSX. Dispatch it. | | "Faster to just write it myself" | Premium tokens on rote work. Spec it, dispatch it, validate in parallel. | | "This part is too hard for codex" | Predicted struggle is not observed struggle. Spec it at pseudocode level and dispatch; you only take over after two failed rounds. | | "I'll let codex commit and push" | Review the diff and run git from this session. | | "No time to write a spec" | An unspecced dispatch comes back wrong and costs more Fable tokens to fix than the spec would have. |

Common Mistakes

• Dispatching without acceptance criteria → codex returns "done" with red tests. Always name the test command that must pass.
• Dispatching frontend work without design intent in the spec → generic UI comes back; the validation loop burns rounds recovering what the spec should have said.
• Blocking on codex → run it in the background; keep doing planning/spec/validation work in parallel.
• Splitting one coherent unit across dispatches → pick one owner per unit; split at the API boundary, not mid-feature.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: blader
• Source: blader/arbitrage
• License: MIT

Install and usage instructions live in the source repository linked above.