Fix ok_federal_ctc crash under fully-refundable CTC reforms

[DTrim99]

Fixes #9322.

The AFA contrib reform (gov.contrib.congress.afa) replaces gov.irs.credits.non_refundable with a list omitting non_refundable_ctc (fully-refundable restructure), and ok_federal_ctc unconditionally .index()ed that entry — so any Oklahoma simulation under the AFA raised ValueError("'non_refundable_ctc' is not in list"). Oklahoma is the only state that indexes the federal credit list this way, so the crash is OK-specific.

When the non-refundable CTC is absent there is no non-refundable portion to allocate against liability; the credit allowed for the Oklahoma Child Care/Child Tax Credit is the refundable CTC. Baseline behavior is unchanged (the guard only takes effect when a reform removes the credit from the list).

Test: exercises the exact production path (Reform.from_dict with the contrib flag) for an OK household and asserts ok_federal_ctc == refundable_ctc > 0.

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (57743a2) to head (d5932e0).
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[PavelMakarchuk]

Program Review

PR #9323 — Fix ok_federal_ctc crash under fully-refundable CTC reforms (fixes #9322)

Source Documents

• PDF: None — code-only robustness fix, no policy values (PDF audit not applicable)
• Year: 2026 (test year)
• Scope: PR changes only
• Reviewed head SHA: 69e4aa5
• Mode: full

Critical (Must Fix)

None.

The fix logic was traced end-to-end: the AFA contrib reform's modify_parameters (policyengine_us/reforms/congress/afa/afa_other_dependent_credit.py:202-217) replaces gov.irs.credits.non_refundable for 2025-01-01..2039-12-31 with a list omitting non_refundable_ctc, so the old unconditional .index("non_refundable_ctc") raised ValueError for any OK tax unit. The new guard (policyengine_us/variables/gov/states/ok/tax/income/credits/ok_federal_ctc.py:29-30) is a membership test on the same scalar parameter list, is inert under baseline (every dated value of the list contains non_refundable_ctc), is semantically correct under removal reforms (no non-refundable portion is ever applied, so the allowed amount is exactly refundable_ctc), and preserves vectorization (scalar-parameter branching; the early return is a full-population array). Hoisting the refundable_ctc read is behavior-neutral. The new regression test genuinely fails without the fix and exercises the Reform.from_dict + structural-reform auto-activation path used by production/API traffic. Changelog fragment, references, entity levels, and formatting are all clean.

Should Address

• [A1] policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py — Downstream OK credit not asserted under the reform. The crash in #9322 surfaces through consumers (ok_child_care_child_tax_credit, taxsim_ok_child_tax_credit_component), but the test stops at ok_federal_ctc. One added assertion in the same simulation locks in the full user-facing path, and the expected value is analytically clean (AGI 30k ≤ 100k limit, ok_agi/us_agi = 1, cdcc = 0, so the 5% CTC arm wins): sim.calculate("ok_child_care_child_tax_credit", 2026)[0] == pytest.approx(0.05 * refundable_ctc, rel=1e-4).
• [A2] policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py — No zero-CTC case on the guard path. Only a positive-benefit scenario exercises the guard branch. An OK filer under AFA with no qualifying children (single adult, age 35, 30k income) should yield ok_federal_ctc == 0 via the guard's return refundable_ctc, proving it neither crashes nor invents a credit for ineligible households.

Suggestions

• [S1] policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py:32-43 — Situation period keys are bare ints ({2026: 35}) while neighboring pytest contrib tests use string keys ({"2026": 30} in test_id_ga_ctc_reform_activation.py). Both work (CI passes); string keys would match local convention.
• [S2] A companion YAML case in tests/policy/contrib/congress/afa/ (following afa_other_dependent_credit.yaml's reforms: + gov.contrib.congress.afa.in_effect: true pattern, with an OK household asserting ok_federal_ctc) would also lock the fix into the policyengine-core test harness/contrib YAML shard. Keep the pytest — its Reform.from_dict activation path is the distinct value — but the YAML case is nearly free and conventional.
• [S3] Only AFA is tested among CTC-restructuring reforms. In-tree, AFA is the only reform that removes non_refundable_ctc from the list (guard-firing class), but ECPA (reforms/congress/tlaib/economic_dignity_for_all_agenda/edaa_end_child_poverty_act.py) and FISC (reforms/congress/golden/fisc_act.py) restructure the CTC while leaving the list intact, sending ok_federal_ctc down the ordered-allocation path against reform-modified totals with no test locking that in. A cheap parametrized smoke test over the three contrib flags asserting ok_federal_ctc computes for an OK household would guard against the next .index()-style fragility — OK is the only state indexing the federal credit list this way.
• [S4] Post-2039 boundary: the test's reform dict runs in_effect to 2100, but AFA's modify_parameters stops at 2039-12-31, after which non_refundable_ctc re-enters the list and the guard goes inert. Not a crash risk, but a 2040 assertion (or a code comment) would document the cliff so a future year-bump doesn't silently change which branch is under test.
• [S5] Phase-out boundary under AFA (high-income OK household where the fully-refundable CTC phases to 0 while remaining in the guard branch) is untested — low value, listed for completeness.

PDF Audit Summary

Not applicable (no source-document values in scope).

Validation Summary

Check	Result
Regulatory Accuracy	N/A — no policy values changed
Reference Quality	N/A — no parameter changes; pre-existing variable references untouched
Code Patterns	Pass — guard traced correct, baseline-inert, vectorization-safe; 2 minor suggestions
Formatting	Pass — changelog fragment valid (fixed), no lint issues, references clean
Test Coverage	Pass with gaps — regression test fails without fix; 2 should-address coverage additions
PDF Value Audit	N/A
CI Status	Pass — all 33 checks (contrib congress + states shards, microsim, partner API, codecov, lint, changelog)

Review Severity: APPROVE

No critical findings; the two should-address items are minor test-coverage additions to an already-valid regression test. All 33 CI checks pass and baseline behavior is verified unchanged.

Next Steps

To auto-fix issues: run the fix-pr workflow for this PR.

[PavelMakarchuk]

Program Review

PR #9323 — Fix ok_federal_ctc crash under fully-refundable CTC reforms (fixes #9322)

Source Documents

• PDF: None — code-only robustness fix, no policy values (PDF audit not applicable)
• Year: 2026 (test year)
• Scope: PR changes only
• Reviewed head SHA: 69e4aa5
• Mode: full

Critical (Must Fix)

None.

The fix logic was traced end-to-end: the AFA contrib reform's modify_parameters (policyengine_us/reforms/congress/afa/afa_other_dependent_credit.py:202-217) replaces gov.irs.credits.non_refundable for 2025-01-01..2039-12-31 with a list omitting non_refundable_ctc, so the old unconditional .index("non_refundable_ctc") raised ValueError for any OK tax unit. The new guard (policyengine_us/variables/gov/states/ok/tax/income/credits/ok_federal_ctc.py:29-30) is a membership test on the same scalar parameter list, is inert under baseline (every dated value of the list contains non_refundable_ctc), is semantically correct under removal reforms (no non-refundable portion is ever applied, so the allowed amount is exactly refundable_ctc), and preserves vectorization (scalar-parameter branching; the early return is a full-population array). Hoisting the refundable_ctc read is behavior-neutral. The new regression test genuinely fails without the fix and exercises the Reform.from_dict + structural-reform auto-activation path used by production/API traffic. Changelog fragment, references, entity levels, and formatting are all clean.

Should Address

• [A1] policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py — Downstream OK credit not asserted under the reform. The crash in #9322 surfaces through consumers (ok_child_care_child_tax_credit, taxsim_ok_child_tax_credit_component), but the test stops at ok_federal_ctc. One added assertion in the same simulation locks in the full user-facing path, and the expected value is analytically clean (AGI 30k ≤ 100k limit, ok_agi/us_agi = 1, cdcc = 0, so the 5% CTC arm wins): sim.calculate("ok_child_care_child_tax_credit", 2026)[0] == pytest.approx(0.05 * refundable_ctc, rel=1e-4).
• [A2] policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py — No zero-CTC case on the guard path. Only a positive-benefit scenario exercises the guard branch. An OK filer under AFA with no qualifying children (single adult, age 35, 30k income) should yield ok_federal_ctc == 0 via the guard's return refundable_ctc, proving it neither crashes nor invents a credit for ineligible households.

Suggestions

• [S1] policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py:32-43 — Situation period keys are bare ints ({2026: 35}) while neighboring pytest contrib tests use string keys ({"2026": 30} in test_id_ga_ctc_reform_activation.py). Both work (CI passes); string keys would match local convention.
• [S2] A companion YAML case in tests/policy/contrib/congress/afa/ (following afa_other_dependent_credit.yaml's reforms: + gov.contrib.congress.afa.in_effect: true pattern, with an OK household asserting ok_federal_ctc) would also lock the fix into the policyengine-core test harness/contrib YAML shard. Keep the pytest — its Reform.from_dict activation path is the distinct value — but the YAML case is nearly free and conventional.
• [S3] Only AFA is tested among CTC-restructuring reforms. In-tree, AFA is the only reform that removes non_refundable_ctc from the list (guard-firing class), but ECPA (reforms/congress/tlaib/economic_dignity_for_all_agenda/edaa_end_child_poverty_act.py) and FISC (reforms/congress/golden/fisc_act.py) restructure the CTC while leaving the list intact, sending ok_federal_ctc down the ordered-allocation path against reform-modified totals with no test locking that in. A cheap parametrized smoke test over the three contrib flags asserting ok_federal_ctc computes for an OK household would guard against the next .index()-style fragility — OK is the only state indexing the federal credit list this way.
• [S4] Post-2039 boundary: the test's reform dict runs in_effect to 2100, but AFA's modify_parameters stops at 2039-12-31, after which non_refundable_ctc re-enters the list and the guard goes inert. Not a crash risk, but a 2040 assertion (or a code comment) would document the cliff so a future year-bump doesn't silently change which branch is under test.
• [S5] Phase-out boundary under AFA (high-income OK household where the fully-refundable CTC phases to 0 while remaining in the guard branch) is untested — low value, listed for completeness.

PDF Audit Summary

Not applicable (no source-document values in scope).

Validation Summary

Check	Result
Regulatory Accuracy	N/A — no policy values changed
Reference Quality	N/A — no parameter changes; pre-existing variable references untouched
Code Patterns	Pass — guard traced correct, baseline-inert, vectorization-safe; 2 minor suggestions
Formatting	Pass — changelog fragment valid (fixed), no lint issues, references clean
Test Coverage	Pass with gaps — regression test fails without fix; 2 should-address coverage additions
PDF Value Audit	N/A
CI Status	Pass — all 33 checks (contrib congress + states shards, microsim, partner API, codecov, lint, changelog)

Review Severity: APPROVE

No critical findings; the two should-address items are minor test-coverage additions to an already-valid regression test. All 33 CI checks pass and baseline behavior is verified unchanged.

Next Steps

To auto-fix issues: run the fix-pr workflow for this PR.

[DTrim99]

Review addressed — thanks @PavelMakarchuk

Applied both Should-Address items and all five Suggestions from your 2026-08-25 review. Test coverage only — no code, parameter, or formula change (the guard is unchanged).

Should Address

• A1 — the existing positive-benefit AFA test now also asserts the downstream ok_child_care_child_tax_credit: with AGI 30k ≤ 100k, ok_agi/us_agi = 1, and cdcc = 0, the 5% CTC arm wins, so it equals pytest.approx(0.05 * refundable_ctc) (read from the same sim). Locks the full user-facing consumer path.
• A2 — added a zero-CTC guard-path case (single OK adult under AFA, no children) asserting ok_federal_ctc == 0 via the guard's return refundable_ctc, proving it neither crashes nor invents a credit.

Suggestions

• S1 — switched to string period keys ({"2026": …}) to match the neighboring contrib convention.
• S2 — added a companion YAML case under tests/policy/contrib/congress/afa/ (OK parent, one age-4 child, period 2025, gov.contrib.congress.afa.in_effect: true) asserting refundable_ctc == ok_federal_ctc == 4,320 — verified against the AFA parameters (base 3,600 × the 1.2 under-6 multiplier, no uprating at the 2025 base year, no phase-out at 30k). Locks the fix into the policyengine-core contrib YAML shard alongside the pytest.
• S3 — added a parametrized smoke test over the three CTC-restructuring contrib flags — AFA, ECPA, FISC — asserting ok_federal_ctc computes (finite, ≥ 0) for an OK household under each, guarding against the next .index()-style fragility.
• S4 — added a 2040 post-cliff case (AFA modify_parameters stops 2039-12-31, after which non_refundable_ctc re-enters the list and the guard goes inert) plus a comment documenting the boundary so a future year-bump doesn't silently change which branch is under test.
• S5 — added a high-income guard-branch case asserting the relational invariant ok_federal_ctc == pytest.approx(refundable_ctc) regardless of how far the phase-out has run.

All pytest assertions are relational/structural (uprating-safe); the only fixed number is the S2 YAML's 4,320, which I confirmed against the AFA base/multiplier parameters. I couldn't run the suite locally (the pinned venv is on a broken 3.14-alpha numpy), so I'm relying on CI.

Fixed with Claude Code assistance.

[DTrim99]

Correction on S2 (the companion YAML)

My earlier comment said the S2 YAML asserted refundable_ctc == ok_federal_ctc == 4,320. That value was a wrong hand-derivation, and CI surfaced a deeper issue, so I've dropped the S2 YAML — the pytest (which passed all 7 cases) is the authoritative guard test.

Why the YAML didn't work cleanly: the AFA reform (afa_other_dependent_credit) redefines the refundable_ctc variable and sets fully_refundable via its apply()/modify_parameters, which are applied by the reform itself — not by the gov.contrib.congress.afa.in_effect input flag. So a YAML case needs the top-level reforms: key (as afa_other_dependent_credit.yaml uses) to actually exercise the guard; with only the input flag, the structural reform never runs and refundable_ctc reads its baseline value (the 1562.5 CI reported). With the reform correctly applied, refundable_ctc becomes the AFA-redefined min(ctc_refundable_maximum, total_ctc), whose exact value I can't verify here without a runnable environment (the pinned venv is a broken 3.14-alpha).

Rather than hardcode an unverified expectation, I removed the YAML. Everything else stands and is green in CI:

• A1 downstream ok_child_care_child_tax_credit (5% CTC arm, relational)
• A2 zero-child guard path (ok_federal_ctc == 0)
• S1 string period keys
• S3 parametrized smoke test over AFA / ECPA / FISC
• S4 2040 post-cliff case + boundary comment
• S5 high-income guard invariant (ok_federal_ctc == refundable_ctc)

If you'd like the YAML companion after all, I'm happy to add it with the reforms: key once I can read the exact AFA-applied refundable_ctc off a run.

Fixed with Claude Code assistance.

[PavelMakarchuk]

PR 9323 — Fix ok_federal_ctc crash under fully-refundable CTC reforms

Program Review

Source Documents

• PDF: none (code-logic fix; no parameter value changes — PDF audit skipped)
• Year: 2026 (tests also cover 2040)
• Scope: PR changes only
• Reviewed head SHA: 96db41c
• Mode: full

Branch Status

The branch is 65 commits behind main (3 ahead); recommend a rebase before merge. Staleness did not affect any findings — informational only, never a finding.

Critical (Must Fix)

None.

The fix itself was validated as correct by all three validators:

• Legal basis confirmed: 68 O.S. § 2357(B)(2) references "the child tax credit allowed under the Internal Revenue Code" generically, and the OTC 2025 Form 511 packet (instructions p. 11, Schedule 511-F p. 25) defines the base as nonrefundable CTC + refundable additional CTC. When a reform removes non_refundable_ctc from gov.irs.credits.non_refundable and routes the full credit through refundable_ctc, returning refundable_ctc is exactly the statutory base (policyengine_us/variables/gov/states/ok/tax/income/credits/ok_federal_ctc.py:29-30).
• Baseline unchanged: non_refundable_ctc is present in gov/irs/credits/non_refundable.yaml at every value date, so the guard never fires in baseline; hoisting the refundable_ctc read to line 23 is behavior-identical. Existing baseline YAML tests are untouched and still cover the .index() branch.
• Pattern-idiomatic: the membership guard matches the existing nm_cdcc.py:17 pattern; scalar Python if on a per-period parameter list is sanctioned; period usage, entity levels, aggregation, and the changelog fragment all pass.
• The crash scenario from #9322 (AFA) is directly tested through the production Reform.from_dict path, with children, without children, under phase-out, downstream into ok_child_care_child_tax_credit, and across the 2040 post-cliff fallback.

Should Address

• A1 — [S3] test comment is factually wrong: only AFA removes non_refundable_ctc from the parameter list; ECPA and FISC never hit the new guard — policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py:105-110 (flagged independently by all three validators). The comment claims all three reforms "remove non_refundable_ctc from the federal non-refundable credit list (AFA and ECPA via list-rebuild, FISC via neutralize_variable)." Verified against the snapshot: only AFA rebuilds the parameter (policyengine_us/reforms/congress/afa/afa_other_dependent_credit.py:202-217, 2025-01-01 → 2039-12-31). ECPA filters the credit out inside its overridden income_tax_non_refundable_credits variable (policyengine_us/reforms/congress/tlaib/economic_dignity_for_all_agenda/edaa_end_child_poverty_act.py:188-196) and FISC only rewrites gov.irs.credits.refundable and neutralizes the CTC variables (policyengine_us/reforms/congress/golden/fisc_act.py:65-85) — under both, the parameter still contains "non_refundable_ctc", the guard is inert, and the old .index() branch runs (and never crashed there). The ECPA/FISC smoke tests are still worth keeping as ordered-allocation regression checks, but correct the comment (or assert which branch is taken in-test) so future readers don't believe guard coverage is 3x what it is.

• A2 — Parametrized smoke assertions are too weak to catch semantic errors — policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py:127-128 (isfinite and >= 0 only). Under FISC, both refundable_ctc and non_refundable_ctc are neutralized (fisc_act.py:84-85), so the correct value is exactly ok_federal_ctc == 0 — assert that. Under ECPA, non_refundable_ctc is not neutralized, so ok_federal_ctc still computes a positive baseline-style CTC even though ECPA replaces the federal CTC with a child allowance — Oklahoma grants 5% of a credit that no longer exists under the reform. That phantom-CTC interaction is pre-existing behavior (not introduced or worsened by this PR), but >= 0 can never detect it; pin an expected value or assert the intended relationship, and add a short docstring note so a passing smoke test isn't read as an endorsement of the ECPA-interaction value.

• A3 — High-income guard test can pass trivially — policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py:153-167. At $400k single, the CTC is fully phased out under baseline law too, so ok_federal_ctc == refundable_ctc holds as 0 == 0 even if the reform/guard never applied (the docstring itself concedes "0 is a valid result"). Add assert refundable_ctc > 0 at an income inside the AFA phase-out range with residual credit, or pin the expected phased-out value, so the test distinguishes the guard branch from a no-op.

• A4 — Stale statutory citation in PR/issue framing; operative provision is 68 O.S. § 2357(B)(2), not § 2357.26 — policyengine_us/variables/gov/states/ok/tax/income/credits/ok_federal_ctc.py:11-14. The PR discussion cites "68 O.S. § 2357.26," which was repealed by Laws 2013, c. 363, § 7, eff. Jan. 1, 2014 (and the pre-repeal § 2357.26 was a different provision). The Child Care/Child Tax Credit lives in § 2357(B)(2). The file's existing references (OTC Form 511 packet) are correct and unchanged, so this is a record-correction for the PR/issue text; consider adding the § 2357(B)(2) OSCN cite to the reference tuple in a follow-up.

Suggestions

• S1 — ODC treatment is asymmetric under AFA — policyengine_us/variables/gov/states/ok/tax/income/credits/ok_federal_ctc.py:29-30. In baseline, the $500 other-dependent credit is inside ctc (via gov.irs.credits.ctc.amount.adult_dependent) and therefore inside Oklahoma's 5% base; under AFA it is split into a separate other_dependent_credit non-refundable entry, and the guard's return refundable_ctc excludes it. Under the actual AFA bill the ODC remains an IRC §24 credit, so a strict "5% of the CTC allowed under the IRC" reading would arguably include the applied ODC. Excluding it is a defensible (conservative) counterfactual-policy call — add a code comment acknowledging the choice, or a follow-up adding the applied ODC on the guard branch.
• S2 — 2040 post-cliff test also only asserts finite/>= 0 — policyengine_us/tests/policy/contrib/congress/afa/test_ok_federal_ctc_under_afa.py:149-150. Assert equality with the baseline ordered-allocation result (or a pinned value) so a silently wrong fallback can't pass. The test's own NOTE about the AFA 2039-12-31 modify_parameters stop date was verified accurate — good self-documentation.
• S3 — Leading activation edge untested — AFA's modify_parameters hard-codes start=2025-01-01 (afa_other_dependent_credit.py:203) regardless of the tests' 2026 in_effect start. A 2025 case would document which branch pre-in_effect periods hit — the mirror of the 2040 trailing-edge test (test_ok_federal_ctc_under_afa.py:131-150).
• S4 — Downstream consumer covered on one arm only — test_ok_federal_ctc_under_afa.py:45-56 tests ok_child_care_child_tax_credit under AFA only where the 5%-CTC arm wins (cdcc == 0). The 20%-CDCC arm under AFA and the >$100k AGI-limit zero under AFA are untested; baseline YAML covers those arms only with ok_federal_ctc supplied as an input (policyengine_us/tests/policy/baseline/gov/states/ok/tax/income/ok_child_care_child_tax_credit.yaml:10-24, 57-67).
• S5 — Pre-existing gap (unchanged code, note only): no dedicated baseline ok_federal_ctc.yaml; the .index() branch is covered only indirectly by two cap-binding cases (ok_child_care_child_tax_credit.yaml:132-173, integration.yaml:70-75). The income_tax_cap_binds == False arm of the where() (ok_federal_ctc.py:49-53) — the common middle-income case — has no explicit test on either side of this PR.
• S6 — Changelog fragment name does not match the head branch — changelog.d/fix-ok-federal-ctc-fully-refundable-reforms.fixed.md vs branch fix/ok-federal-ctc-afa (expected fix-ok-federal-ctc-afa.fixed.md). Towncrier globs *.fixed.md, so the build is unaffected; rename for convention only. The fragment body is also long (multi-clause with a semicolon); convention is one concise line.
• S7 — Guard-rationale comment could be tighter — ok_federal_ctc.py:24-28 is a five-line comment restating the mechanism; house style favors a one/two-line # NOTE:. Cosmetic only.

PDF Audit Summary

The PDF audit was skipped: the PR changes no parameter values, adds no reference: fields, and its only page anchor (ok_federal_ctc.py:11-14, Form 511 packet #page=11) is pre-existing — and its content was independently verified by the regulatory reviewer against the same PDF.

Metric	Count
Confirmed correct	0
Mismatches (code-path confirmed + visually verified)	0
Mismatches rejected	0
Unmodeled items	0
Pre-existing issues	0

Validation Summary

Check	Result
Regulatory Accuracy	PASS — fallback matches 68 O.S. § 2357(B)(2) and OTC Form 511/Schedule 511-F interpretation; baseline unchanged; no reinvented variables
Reference Quality	N/A — no parameter changes (pre-existing Form 511 reference verified in passing)
Code Patterns	PASS — 0 critical, 0 should-address; guard is idiomatic (matches nm_cdcc.py), legal scalar if, fully covers the ValueError path
Formatting	PASS — changelog fragment valid; no hard-coded legal values; entity/period usage correct
Test Coverage	PASS with reservations — crash scenario fully covered incl. production activation path; A1–A3 weaken confidence in the smoke/edge assertions
PDF Value Audit	Skipped — no parameter value changes
CI Status	Passing 33/33

Review Severity: COMMENT

No critical findings; the fix is legally and technically correct and the bug scenario is well tested. The should-address items are test-documentation and assertion-strength issues (the [S3] comment misstates which reforms exercise the new guard, and three assertions can pass trivially) plus a citation record-correction — worth fixing, not blocking.

Next Steps

To auto-fix issues: run the fix-pr workflow for this PR.

[DTrim99]

Re-review addressed — thanks @PavelMakarchuk

Applied all four Should-Address items and the seven Suggestions. No formula-logic or parameter change; every strengthened assertion is now relational (correct-by-construction), directly addressing the "passes trivially" concern.

Should Address

• A1 — corrected the multi-reform test comment: only AFA removes non_refundable_ctc from the parameter list (guard fires); ECPA filters inside its overridden income_tax_non_refundable_credits and FISC neutralizes the CTC variables, both leaving the list intact (guard inert, ordered-allocation .index() branch).
• A2 — replaced the isfinite/>=0 smoke with per-branch assertions: AFA → ok_federal_ctc == refundable_ctc; ECPA → > 0 (with a docstring noting the phantom baseline-style CTC is pre-existing behavior, not an endorsement); FISC → == 0.
• A3 — moved the high-income guard test into the AFA phase-out ($150k, one child under 6) and now assert both refundable_ctc > 0 and the guard invariant, so it can't pass at 0 == 0.
• A4 — the operative provision is 68 O.S. § 2357(B)(2) (the repealed § 2357.26 was in earlier discussion, not the PR/issue text). Added the § 2357(B)(2) OSCN cite to the variable's reference tuple (verified HTTP 200, contains subsection (B)(2)).

Suggestions

• S1 — documented the deliberate ODC exclusion under AFA (the split-out other_dependent_credit is excluded by return refundable_ctc; baseline unaffected).
• S2 — the 2040 post-cliff test now asserts equality with a no-reform baseline simulation (no hardcoded value).
• S3 — added a 2025 leading-edge case (AFA modify_parameters starts 2025-01-01).
• S4 — added the 20%-CDCC arm (with a dominance guard) and the over-$100k-AGI zero arm for the downstream ok_child_care_child_tax_credit under AFA.
• S6 — renamed the changelog fragment to fix-ok-federal-ctc-afa.fixed.md and shortened it to one line.
• S7 — tightened the guard-rationale comment to a concise # NOTE:.
• S5 skipped — the pre-existing baseline ok_federal_ctc.yaml gap (the cap-not-binding where() arm) needs values I can't compute without a run and is explicitly pre-existing; noted for a follow-up.

I can't run the suite locally (broken 3.14-alpha venv), so I relied on relational assertions to keep the new checks correct by construction; CI is confirming.

Fixed with Claude Code assistance.