ecfr-title-26
backlog row · status candidate · category STD (Standards, specs & regulations) · lane A · refresh pinned
What an agent uses it for
an agent answering federal tax questions queries this for what the Treasury regulations actually say — de minimis safe harbor, estimated-tax safe harbor, home-office exclusive use (demand: tax Ask-HN volume 40)
Use it
xerj corpus add --from https://raw.githubusercontent.com/xerj-org/xerj/corpus-hub/tools/xerj-code/hub/ecfr-title-26.jsonxerj corpus index ecfr-title-26 → xerj code ecfr-title-26 "your question"Sources & pins
| source | pin | licence | size | review note |
|---|---|---|---|---|
| https://www.govinfo.gov/bulkdata/ECFR/title-26/ECFR-title26.xml | recipe | ? | curated pack | public domain (US government work, 17 USC 105); pinned mirror github.com/xerj-org/corpus-ecfr-title-26 |
— across — · added —
Rights
? — see per-source review blocks . The review block records a human opening each licence file at the pin; detector output is a hint, never the verdict.
Retrieval spot-check (G7)
median 1.0/5 relevant — 2026-10-02T22:25:00Z
Q: What is the de minimis safe harbor amount for expensing tangible property without an applicable financial statement?
expect: 26 CFR 1.263(a)-1(f): $5,000 per item/invoice with AFS, $2,500 without
top-5: part-1/sec-1.162-3 · part-1/sec-1.263(a)-1 · part-1/sec-1.263(a)-0 · part-1/sec-1.162-3 · part-1/sec-1.263(a)-1
grade: relevant
expect: 26 CFR 1.263(a)-1(f): $5,000 per item/invoice with AFS, $2,500 without
top-5: part-1/sec-1.162-3 · part-1/sec-1.263(a)-1 · part-1/sec-1.263(a)-0 · part-1/sec-1.162-3 · part-1/sec-1.263(a)-1
grade: relevant
Q: What prior-year safe harbor avoids the estimated tax underpayment penalty?
expect: 26 CFR 1.6654-2(d): 100% of prior-year tax (110% if AGI > $150k), else 90% current year
top-5: part-1/sec-1.1446-3 · part-1/sec-1.1446-0 · part-1/sec-1.6655-2T · part-1/sec-1.1446-3 · part-1/sec-1.904-7
grade: miss
expect: 26 CFR 1.6654-2(d): 100% of prior-year tax (110% if AGI > $150k), else 90% current year
top-5: part-1/sec-1.1446-3 · part-1/sec-1.1446-0 · part-1/sec-1.6655-2T · part-1/sec-1.1446-3 · part-1/sec-1.904-7
grade: miss
Q: What use must a home office satisfy to qualify for the deduction?
expect: 26 CFR 1.280A-2: exclusive and regular use as principal place of business
top-5: part-1/sec-1.1441-1 · part-1/sec-1.274-5 · part-1/sec-1.280F-6 · part-1/sec-1.817-2 · part-1/sec-1.1503(d)-1
grade: suite-defect (excluded)
expect: 26 CFR 1.280A-2: exclusive and regular use as principal place of business
top-5: part-1/sec-1.1441-1 · part-1/sec-1.274-5 · part-1/sec-1.280F-6 · part-1/sec-1.817-2 · part-1/sec-1.1503(d)-1
grade: suite-defect (excluded)
Q: How long must employers keep employment tax records?
expect: 26 CFR 31.6001-1 / related: at least 4 years after the due date or payment date
top-5: part-31/sec-31.6001-2 · part-35/sec-35.3405-1T · part-31/sec-31.6001-3 · part-1/sec-1.274-6T · part-1/sec-1.475(a)-4
grade: miss
expect: 26 CFR 31.6001-1 / related: at least 4 years after the due date or payment date
top-5: part-31/sec-31.6001-2 · part-35/sec-35.3405-1T · part-31/sec-31.6001-3 · part-1/sec-1.274-6T · part-1/sec-1.475(a)-4
grade: miss
Q: Which property qualifies for the section 179 expensing election?
expect: 26 CFR 1.179-1/.179-2: tangible personal property, certain off-the-shelf software, qualified real property
top-5: part-1/sec-1.179-1 · part-1/sec-1.179-3 · part-1/sec-1.179-1 · part-1/sec-1.179-3 · part-1/sec-1.179-1
grade: partial
expect: 26 CFR 1.179-1/.179-2: tangible personal property, certain off-the-shelf software, qualified real property
top-5: part-1/sec-1.179-1 · part-1/sec-1.179-3 · part-1/sec-1.179-1 · part-1/sec-1.179-3 · part-1/sec-1.179-1
grade: partial