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Recipe: Write a Headline-Chase Plan

A runnable Kestrel recipe for a momentum PLAN that fires on a break above the high-of-day and informs the agent after the fill.

Answer card

A headline-chase belongs in a PLAN, not a prompt. You author a standing, bounded-risk contingent program: WHEN spot breaks the high-of-day AND velocity is top-percentile, DO buy a call at a fair-capped peg, TP into strength, EXIT on giveback. The runtime fires it in milliseconds and wakes you in parallel: fire-then-inform. An LLM round-trip cannot chase a breakout; a compiled Plan can. Copy the fence, adapt the generic instruments, arm it in your pod.

Why this is a Plan, not a prompt

Momentum decays in seconds. If your agent has to perceive the break, reason, and emit an order, the edge is gone before the tokens finish streaming. Kestrel splits the job: judgment is authored ahead of time; execution is a reflex the runtime owns. You arm the intent once; the runtime holds the trigger and fires at machine speed. The agent is never in the hot path.

This is the Interface Thesis in one recipe: the two failures of LLM trading are perception and latency; interface, not intelligence.

The recipe

Illustrative only, generic instruments (SPX signal, SPY 0dte exec). This is how an agent could express a momentum chase, not a strategy recommendation. You arm it inside your own pod.

IMPORT { bracket-standard } FROM "./armory/momentum.kestrel"
USING signal SPX exec SPY 0dte

PLAN headline-chase budget 0.25R ttl 15:55 regime {intraday: trend}
  WHEN spot > HOD AND velocity(5m) >= p95
  DO buy 1 +1 C @ min(fair, mid) peg cap fair
  RELOAD WHEN spot > HOD held 30s buy 1 +1 C @ min(fair, mid) peg cap fair
  TP 2.5x frac 0.5 @ fair
  EXIT spot < VWAP held 120s @ fair
  INVALIDATE velocity(5m) < p50

Read it line by line:

  • budget 0.25R ttl 15:55: worst case is a quarter-R; the Plan self-expires before the close. Bounded risk and a mandatory TTL are structural, not optional.
  • WHEN spot > HOD AND velocity(5m) >= p95: the trigger is series × predicates over the trigger algebra. Break the high-of-day and be in the top-5% velocity regime. Both must hold.
  • DO buy 1 +1 C @ min(fair, mid) peg cap fair: buy one out-of-the-money call, priced at the cheaper of fair value or mid, pegged, and capped at fair so a runaway quote can never lift you above intrinsic-plus. A quote is not a value: you anchor to fair, not to whatever the book is screaming.
  • RELOAD WHEN ...: add a second clip only if the break holds 30 seconds. You press a real move, not a wick.
  • TP 2.5x frac 0.5 @ fair: take half off at 2.5×, priced to fair. Bank the spike; ride the rest.
  • EXIT spot < VWAP held 120s: giveback rule. Lose VWAP for two minutes and you're out.
  • INVALIDATE velocity(5m) < p50: if momentum dies, the thesis is void and the plan stands down (don't ride it).

Watch it, don't poll it

Pair the Plan with a Wake so you learn why it fired without babysitting a screen. A Wake spends attention, never risk.

WAKE chase-filled
  WHEN filled
  DELIVER frame-momentum
  BUDGET 20 wakes/day

The runtime fills first and delivers a compact Frame (a chart-in-text) after. Perception cost is O(new bars), not O(screen).

Where this is not the fit

  • Chop. The regime {intraday: trend} tag exists because this Plan is a loss machine in a range. Gate it or don't arm it.
  • Illiquid names. cap fair protects you, but a wide, thin book turns every peg into slippage. Keep exec instruments liquid.
  • Backtest romance. Deploy to SIM, then PAPER, and read the honest Grade before real capital. A Grade is never flattering when it's contamination-fenced.

Ship it

Arm in SIM → promote to PAPER → read the Grade → and only a human signs the LIVE Envelope. The template is yours to adapt; the discipline (bounded R, mandatory TTL, fair-capped fills, fire-then-inform) is the point.

The Kestrel language and runtime are open source. As of mid-2026: anonymous trial sims, certified Grades, shareable proof URLs, and 402 Offers with Stripe settlement are live; always-on paper presence and the human-signed live path are in build. The free tier needs no signup. This recipe is illustrative, a demonstration of how an agent could express a momentum chase in the grammar, not a strategy to run and not investment advice.

A headline-chase is a PLAN, not a prompt: the runtime fires the break in milliseconds and wakes you after the fill; the agent is never in the hot path.