Codex gpt-5.6-terra on “A proposal to the chief executive”: no change with Minto

Structure 2 → 2 of 8 0 Quality 8 → 8 of 10 0

The judge on the output with Minto

The answer and appended skeleton both organize the same feasibility mechanics, making the delivery more repetitive than necessary.

Mode write · case 01-big-chief · run v1.7.0-final

Structure of 8, 2 points per axis
Structure	Without Minto 2	With Minto 2
Top	1	1
Key-line composition	0	0
Levels	0	0
Order and kind	1	1

Quality of 10, 2 points per axis
Quality	Without Minto 8	With Minto 8
Top	1	1
Same-kind grouping	2	2
Explainable order	2	2
MECE	2	2
Visible, proportionate structure	1	1

Outputs and the judge’s words are quoted as written, in English.

Without Minto With Minto

Without Minto

control prompt · blind label out-10

No hard failures

The concise prose preserves the main workflow but leaves the hierarchy only partly visible and does not cross from feasibility to recommendation.

To: Robert Salton
From: John Jackson
Subject: Big Chief electronic monthly settlement request

Big Chief’s request can be accommodated, provided its monthly file contains the required delivery-ticket identifiers and is balanced to its prepaid payment.

Big Chief should submit a monthly accounts-payable extract in the national-accounts cash-receipt format, containing the parent number, outlet number, ticket number, ticket amount, and delivery date. If it cannot supply the parent and outlet numbers initially, we can provide them from the customer master file for future submissions.

Big Chief should send the file to Data Processing and send its cheque, with a detailed listing, to the lockbox. Finance will balance the file under the prescribed procedure; the cheque total and file detail must net to zero.

After balancing, the file can be processed through the national-accounts system to match ticket numbers against statement history and produce the relevant billing records.

With Minto

prompt with the skill · blind label out-06

No hard failures

The answer and appended skeleton both organize the same feasibility mechanics, making the delivery more repetitive than necessary.

Subject: Big Chief’s proposed monthly file and single payment can be processed through our national-accounts settlement procedure.

Big Chief wants to replace individual delivery-ticket settlement for account 8306 with a monthly electronic file and one prepaid payment. We can accommodate the request provided the submission meets the existing file, balancing, and matching requirements.

The monthly file must identify and support each delivery.
- Include parent number, outlet number, ticket number, ticket amount, and delivery date.
- If Big Chief cannot provide the parent and outlet numbers initially, we can supply them from the customer master file for later submissions.
The file and payment must reconcile before processing.
- Big Chief will send its accounts-payable extract to Data Processing and its cheque with a detailed listing to the lockbox.
- Finance will balance the file under the prescribed procedure; the cheque total and file detail must net to zero.
The reconciled file can enter the existing national-accounts process.
- Big Chief’s file will use the format accepted by the national-accounts cash-receipt system.
- After balancing, the system will match ticket numbers against statement history and produce the relevant billing records.

Top: Big Chief’s proposed monthly file and single payment can be processed through our national-accounts settlement procedure.

Each delivery can be identified in the required file format.
The monthly file and payment can be balanced under the prescribed procedure.
The reconciled file can be matched and processed through the national-accounts system.

The judge

Recurring defect	without	with Minto
Feasibility or implementation replaces the acceptance decisionthe skill has the rule; the model did not follow it · Core loop §1–2, reader question and provisional answer	present	present
Mechanics occupy the first level instead of grounded reasonsthe skill has the rule; the model did not follow it · Core loop §4, Groups	present	present
Literal reader question is absentthe skill has the rule; the model did not follow it · Core loop §1 and §3	present	present
Situation and complication are not both visible before supportthe skill has no such rule · Core loop §3, SCQ intro	present	absent

Decisive questions

without Kind: mechanics; grounded elements: 3; top establishes accommodation, not acceptance; no inventions; the three process paragraphs remain the key line; reader question absent.
with Minto Kind: mechanics; grounded elements: 3; top answers processability rather than acceptance; no inventions; mechanics remain first-level requirements and are repeated in the skeleton; reader question absent.

Judge’s check	without	with Minto
Answer first	yes	yes
First-level elements	3	3
First-level kind matches the gold	no	no
Invented facts	no	no
Source lost without a note	no	no
Mode respected	yes	yes
Reader’s question stated literally	no	no
Order type named	no	no
SCQ introduction present	no	yes

How the test was built

Codex gpt-5.6-terra received the same task twice. The control prompt is one framing line and the task. The prompt with Minto is the same task preceded by the full text of the skill. The judge read both outputs among 16 under blind labels and did not know which one had the skill.

Prompt without Minto 2 147 B

You are working on a business document using the Minto Pyramid Principle.

<!-- Faithful paraphrase of Barbara Minto, The Minto Pyramid Principle
     (2010), Chapter 3, Exhibit 5 and the surrounding top-down analysis.
     The wording is original to this evaluation fixture. -->

# Fixture 01: Big Chief proposal

**Mode:** `write`
**Language:** `en`

## Context

The company supplies beverages. Drivers send delivery tickets to Finance; each
ticket identifies the customer, outlet, delivery, amount, and date. The tickets
feed the national-accounts settlement process.

Big Chief, a major multi-outlet customer, wants to replace individual ticket
settlement with a monthly computer file and one payment. Finance reviewed how
the proposed process would work and sent management the memo below.

## Before

```text
To: Robert Salton
From: John Jackson
Subject: Big Chief request

We reviewed Big Chief account 8306's request to submit delivery-ticket data
electronically and settle it through one prepaid monthly payment. Our findings
follow.

1. Any external account file must contain the parent number, outlet number,
   ticket number, ticket amount, and delivery date. If Big Chief cannot provide
   the first two identifiers, we can supply them from the customer master file
   for inclusion in later submissions.

2. Big Chief will build an extraction program for its accounts-payable file.
   The resulting file will use the format accepted by our national-accounts
   cash-receipt system. Big Chief will send the file to Data Processing and
   send its cheque, with a detailed listing, to the lockbox. We will balance
   the file under the prescribed procedure. The cheque total and file detail
   must net to zero.

3. Once balanced, the monthly file will run through the national-accounts
   system, match ticket numbers against statement history, and produce the
   relevant billing records.
```

## Task

Rewrite this as a short management memo using the Minto Pyramid Principle.
Do not invent benefits, savings, or operational facts that are absent from the
source.

Return only the result, with no explanation of how you produced it.

Prompt with Minto five parts, in order · 29 720 B

Below is a skill written as an instruction. Read it in full and apply it to the task at the end.
===== SKILL.md ===== SKILL.md at f4813ce 17 235 B
===== references/rules.md ===== references/rules.md at f4813ce 6 464 B
===== references/templates.md ===== references/templates.md at f4813ce 3 742 B
===== TASK ===== the whole case input
Return only the result, with no explanation of how you produced it.

Case input before.md

Fixture 01: Big Chief proposal

Mode: write
Language: en

Context

The company supplies beverages. Drivers send delivery tickets to Finance; each
ticket identifies the customer, outlet, delivery, amount, and date. The tickets
feed the national-accounts settlement process.

Big Chief, a major multi-outlet customer, wants to replace individual ticket
settlement with a monthly computer file and one payment. Finance reviewed how
the proposed process would work and sent management the memo below.

Before

To: Robert Salton
                From: John Jackson
                Subject: Big Chief request
                
                We reviewed Big Chief account 8306's request to submit delivery-ticket data
                electronically and settle it through one prepaid monthly payment. Our findings
                follow.
                
                1. Any external account file must contain the parent number, outlet number,
                   ticket number, ticket amount, and delivery date. If Big Chief cannot provide
                   the first two identifiers, we can supply them from the customer master file
                   for inclusion in later submissions.
                
                2. Big Chief will build an extraction program for its accounts-payable file.
                   The resulting file will use the format accepted by our national-accounts
                   cash-receipt system. Big Chief will send the file to Data Processing and
                   send its cheque, with a detailed listing, to the lockbox. We will balance
                   the file under the prescribed procedure. The cheque total and file detail
                   must net to zero.
                
                3. Once balanced, the monthly file will run through the national-accounts
                   system, match ticket numbers against statement history, and produce the
                   relevant billing records.

Task

Rewrite this as a short management memo using the Minto Pyramid Principle.
Do not invent benefits, savings, or operational facts that are absent from the
source.

The judge’s gold gold.md

Gold 01: Big Chief proposal

Source structure: Minto (2010), Chapter 3, Exhibits 4-6.

Expected structure

Element	Expected value
Reader question	Is Big Chief's proposal a good idea?
Top	Yes, the proposed process is workable and worth accepting, within the evidence available
Key-line kind	Reasons or reader benefits, not system mechanics
Order	Inductive reasons supporting one conclusion

The book illustrates three possible benefits: obtaining the required
information, increasing cash flow, and reducing clerical work. Only the first
is directly supported by this fixture. Literal reproduction of all three is
therefore not required and unsupported benefits count as inventions.

Strong outputs:

answer the management question before explaining the file mechanics;
use two to four same-kind reasons grounded in the supplied facts;
place field lists, file format, routing, balancing, and matching below those
reasons as evidence or implementation detail;
retain the literal reader question in the delivered memo.

Main defect in the source

The source explains how the proposed system would operate but never answers
whether management should accept it. A technically tidy list is still the wrong
key line if the reader is deciding whether to act.

Scoring notes

2 for key-line composition: every first-level point is a grounded benefit,
loss avoided, or reason for acceptance.
1: benefits and mechanics are mixed.
0: the first level is entirely fields, file handling, or balancing steps.

Do not reward unsupported claims about savings, speed, or cash flow.

Judge gpt-5.6-sol, effort high · Codex gpt-5.6-terra, effort low · skill from commit f4813ce · run v1.7.0-final