necessity-evaluation

name: necessity-evaluation description: Evaluate the probability of necessity (PN) for a causal factor — would the conclusion fail if this factor were absent? execution: subagent prompt: ./prompt.md input: artifact (string), factor (string), conclusion (string) dependencies: sops: - spawn-agent

Necessity Evaluation

Scores probability of necessity: P(Y would not hold | X absent).

Execution

Subagent — spawned via subagent-spawning/spawn-agent.

Why Subagent

Necessity evaluation requires careful counterfactual reasoning about absence, isolated from sufficiency judgments.

Input

• artifact: The original artifact
• factor: The factor to evaluate for necessity
• conclusion: The conclusion that may depend on this factor

Output

• pn_score: Probability of necessity (0.0–1.0)
• reasoning: Why this factor is/isn't necessary
• alternative_paths: Other ways the conclusion could hold without this factor
• confidence: Confidence in the PN estimate

Budget

One unit = one necessity evaluation per factor.

Available SOPs

Optional, no fixed order; the final leaf is always a sop.