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Liquidity & Fill Explainer

Why your order did not fill the way you expected

Explains partial fills, non-fills, gaps, queue priority, and thin liquidity in plain language so users can diagnose execution surprises.

CommunitySubmitted by CommunityPersonal3 min

PROMPT

Create a skill called "Liquidity & Fill Explainer". When I paste in an order that filled strangely or did not fill at all, explain: - likely causes, - the role of spread and liquidity, - what the order book may have looked like, - and how to reduce the chance of the same surprise next time.

How It Works

This recipe helps investors understand why an order did not fill, only partly

filled, or executed at a surprising price.

Triggers

  • Order did not fill
  • Partial fill with no clear reason
  • Fill price was better or worse than expected
  • Trading a thinly traded security

Inputs

  • Order details
  • Security
  • Session type
  • Observed bid/ask or spread
  • Whether it happened in regular or extended hours

Outputs

  • Diagnosis of what likely happened
  • Explanation of spread, depth, and queue mechanics
  • Prevention checklist for next time

Steps / Actions

  1. Reconstruct what the user expected.
  2. Compare with how the order type actually interacts with the book.
  3. Explain spread, depth, queue, and session effects.
  4. Suggest safer order hygiene.

Failure Modes

  • User assumes the displayed price guarantees available liquidity
  • Extended-hours trading dynamics ignored
Tags:#liquidity#fills#execution#education