Arc Skills / Requirements

Identify conflicting requirements in a specification

Arc Skills screens a bounded requirement set for overlapping conditions and incompatible actions. It returns pairwise findings with the exact shared situation and the smallest owner decision needed.

Use this skill

Use Arc Skills to identify conflicting obligations in the supplied requirement set.

Inputs:
- Controlled requirement baseline with exact IDs and wording
- Definitions of modes, configurations, subjects, units, and exceptions
- Applicable source precedence or priority rules, if approved

Return a pairwise table with overlap condition, hard or apparent conflict verdict, and owner question.
Test simultaneous satisfaction in the same situation. Preserve original statements and do not choose a winner from ID order

Set up the toolkit · Read the skill instructions

What you provide and what you get

Inputs and outputs
What you have	How it is used	What you get
Controlled requirements	Defines actions, modes, and objects	Pairwise candidate set
Mode and component definitions	Determines whether conditions truly overlap	Hard or apparent verdict
Precedence evidence	Constrains authorized resolution	Owner decision question

Heater behavior in safe mode

Illustrative engineering example.

The specification contains three heater statements. The architecture excerpt says H-1 is the only heater in the unit, but the safe-mode priority policy is missing.

R-1: In safe mode the heater H-1 shall remain off.
R-2: In safe mode the unit shall maintain 20 °C by energizing H-1.
R-3: In normal mode the unit shall maintain 20 °C by energizing H-1.

Heater behavior in safe mode — illustrative output
Pair	Overlap and verdict	Decision needed
R-1 / R-2	Same safe mode and H-1; hard conflict if maintain temperature requires H-1 energization.	Mode owner chooses allowable heater behavior and revises one duty.
R-1 / R-3	Safe versus normal modes; no shared mode in supplied definitions.	No conflict unless transition rules introduce overlap.
R-2 / R-3	Same target in different modes; compatible as written.	No change needed from this pair review.

The R-1/R-2 finding is grounded in a shared safe-mode condition and one heater, not a keyword match. Simultaneous compliance is impossible when R-2 calls for energizing H-1 while R-1 forbids it.

The other pairs are included to show the boundary of the finding. If safe mode has submodes or a second heater exists in a later configuration, the verdict must be revisited rather than silently resolved here.

Test simultaneous satisfiability

Normalize each actor, object, mode, action, quantity, and exception.
Find pairs with a shared operating situation and configuration.
Ask whether one implementation can satisfy both exact obligations there.
Record a narrow reconciliation question and the accountable decision owner.

Questions about this task

Are opposite verbs always a conflict?

Only when they apply to the same object under overlapping conditions. Here H-1 and safe mode establish that overlap.

Which requirement takes precedence?

Use a controlled precedence decision if one exists. Without it, identify the conflict and ask the responsible owner.

Sources and further reading

NASA Systems Engineering Handbook: Lifecycle and requirements guidance; the example decisions are illustrative.