determine_dependent

Candidate is the taxpayer's child, stepchild, foster child, sibling, step-sibling, or a descendant of any of them (§ 152(c)(2)).

Candidate was a full-time student for at least 5 months (§ 152(f)(2)).

Candidate is permanently and totally disabled (§ 152(c)(3)(B)).

Candidate is younger than the taxpayer (§ 152(c)(3)(A)).

Candidate had the same principal residence as the taxpayer for more than half the year (§ 152(c)(1)(B)).

Candidate provided more than half of their own support (§ 152(c)(1)(D)).

Candidate files a joint return with a spouse (other than a refund-only claim) (§ 152(c)(1)(E)).

Candidate bears a § 152(d)(2) relationship to the taxpayer (parent, grandparent, sibling, in-law, etc.) or lived in the household all year.

The taxpayer provided more than half of the candidate's support (§ 152(d)(1)(C)).

Candidate is the qualifying child of the taxpayer or any other taxpayer (§ 152(d)(1)(D)).

A § 152(d)(3) multiple-support agreement is in place for the candidate: the group together provided over half the support, no one person provided over half, each member could otherwise claim the candidate, and every other over-10% contributor signed a Form 2120 waiver.

The taxpayer contributed over 10 percent of the candidate's support (§ 152(d)(3)(D) — the support test under a multiple-support agreement).

§ 152(e) applies to the candidate child: the parents are divorced, separated, or lived apart the last 6 months of the year; the child received over half their support from the parents and was in their custody over half the year.

The taxpayer is the custodial parent (the parent with whom the child resided the greater number of nights, § 152(e)(4)(A)).

The custodial parent signed a written declaration (Form 8332) releasing the claim to the child for this year (§ 152(e)(2)).

rule to derive (default: us.federal.dependent.is_dependent). Other targets: us.federal.dependent.qualifying_child, us.federal.dependent.qualifying_relative

REQUIRED for computation: the law-in-force date — use the intended tax year's year-end (e.g. "2025-12-31" for TY2025). Omitting it is an error, never a default.

include the full proof artifact in the response as proof (PROOF-FORMAT v2: every applied rule, input, assumption and rounding, verifiable offline against corpusMerkleRoot; ~200 KB). Default false — the hashes alone are returned.