Agentic PDLC 4 · Four calculations, in order

[akash-coded]

Four calculations, in order

Exercise 2 · 12 minutes

Each step feeds the next. Work down the page and do not skip ahead.

A cargo terminal wants an agent to answer the question customers ask most: where is my shipment, and when will it clear customs.

Step 1 · Price one wrong answer

A wrong clearance estimate sends a truck to the wrong place at the wrong time. Add the three lines.

What goes wrong	Cost
Wasted truck slot and driver hours	$18
Storage charged for an extra day	$21
Agent time to unpick and re-book	$6
Damage, one wrong answer	______

An agent handling this by hand costs $15 a case.

Step 2 · Turn the damage into a bar

The calculation	Your answer
Damage divided by saving	______
So one wrong in how many is affordable	______
Which means the bar is	______ percent

Evaluation on real cases puts the system at 74 percent. Does it clear?

(a) Yes, comfortably (b) Yes, but only just (c) No (d) Cannot be told from this

Step 3 · Choose the coverage

Someone has already run the hundred-case count using the damage from step 1. The last column is the two before it, subtracted.

Setting	It attempts	Right	Wrong	Rights save	Wrongs cost	Net per hundred
Tight	30	29	1	$435	$45	+$390
Balanced	50	46	4	$690	$180	+$510
Loose	70	58	12	$870	$540	+$330
Very loose	90	63	27	$945	$1,215	-$270

3.1 Which setting would you launch at?

(a) Balanced (b) Very loose (c) Tight (d) Loose

3.2 The team proposes Very loose, on the grounds that it handles the most cases. In one line, what is wrong with that?

(a) The accuracy on the covered cases falls below the bar that the damage figure implies
(b) Ninety percent coverage exceeds what the tool contracts in step four actually permit
(c) The cost per attempt rises as coverage grows, which erodes the saving from the extra cases
(d) The extra cases are the ones it is least sure about, so their mistakes outweigh the gains

Step 4 · Read the ceiling off the tools

Tool	Changes anything?	Can it be undone?	Material if wrong?	Highest level
Look up a shipment	No	Not applicable	No
Book a customs inspection slot	Yes	Yes, same day only	Yes
Send the customer an update	Yes	No	No
Release a shipment from bond	Yes	No	Yes

4.1 What is the agent's ceiling, and which tool sets it?

(a) L1, set by sending the customer an update
(b) L2, set by booking a customs inspection slot
(c) L1, set by releasing a shipment from bond
(d) L4, because two of the four tools are safe

4.2 You want the agent above draft. Which move is cheapest?

(a) Retrain the model on several years of historical shipment and clearance records
(b) Tighten the confidence threshold so it attempts fewer cases
(c) Add a fourth tool that reverses a bond release
(d) Take the bond release out of the agent's tool set and route it to a person

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Paste your answers as one line, for example:
1 $45 | 2 3, 4, 75 | 2b 3.1a 3.2d 4.1c 4.2d

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Marking scheme, out of 12

Step	Answer	Marks	Why
1	$45	2	18 + 21 + 6. Nothing else on the page belongs in the damage. The agent time in the last row is the time to put it right, not the time it would have taken anyway.
2	3, then 4, then 75 percent	3	45 divided by 15 is 3, so three right answers pay for one wrong one, so one wrong in four is affordable, which is 3 of 4 or 75 percent.
2 verdict	b	1	74 against a bar of 75 is below it, but by one point. Option c is the trap: at that margin the honest answer is that it does not clear, and it is one guardrail away from clearing comfortably.
3.1	a	2	Balanced returns the most per hundred. The largest coverage is not the largest return, and the table shows the reversal.
3.2	d	2	Option a is the near miss and it is precise about the wrong thing. Accuracy at Very loose is 70 percent, which is below the bar, but the reason the money goes negative is the arithmetic in the last two columns rather than the bar.
4.1	c	1	Look up is read only, so L4. The update changes something but is not material, so L4. The inspection slot is material and reversible the same day, so L2. The bond release is material and irreversible, so L1, and the ceiling is the lowest of the four.
4.2	d	1	The ceiling is set by one tool. Removing it lifts the agent to L2 and leaves a person in the one place that genuinely needs one. Retraining does not move a ceiling set by reversibility, and the threshold changes coverage rather than autonomy.

Step 2 answered no, and step 4 found the ceiling at draft. Both have the same fix available: change the design rather than the model.