State and local tax: Claude skills backed by tested code

Analysis only. No tool in this server places orders, modifies custodian records or files returns. This server holds no client data: every figure arrives in the call and nothing is stored. Results are estimates over those figures, not a return and not tax advice. No state's own income tax is computed. No state pack is bound in this deployment, and the cap limits a federal deduction rather than telling you what a state charges.

What taxagent-salt computes

3 commands, every one callable over MCP. Every result carries the method it used, the rule pack it was pinned to, what is still missing and whether coverage was complete, for a licensed professional to review.

CommandWhat it returnsWhat it needs
calculate_salt_capThe federal cap phasing down at 30 cents per dollar of MAGI above the threshold, to a floor. Not a cliff.nothing required
calculate_state_coverageWhich states' own tax this deployment can compute, and what a state pack would have to contain.nothing required
get_salt_capabilitiesWhich calculators taxagent-salt exposes, what it will not compute, and the rule pack its figures are pinned to.nothing required

When to use it

The federal cap on deducting state and local tax. It holds no client data: every figure arrives in the call and nothing is stored.

Requests it answers:

  • “How much state and local tax can I deduct?”
  • “Which states' own income tax can this compute?”
  • “What does this server know about state tax?”

Skills that route here, each with the moment it applies:

salt-review

Someone asks how much of their state and local tax is deductible, or how the cap changes as income rises. Users often say "state tax" when they mean the federal deduction for it, and the reverse. Establish which they mean before answering.

Compute the federal cap on deducting state and local tax, including its phase-down, and report what this deployment can say about an individual state's own tax. No state's own income tax is computed in this release.

What it does not do

Named here because leaving it out is how an agent ends up asserting something the code never computed. Each line is the registry's own wording, not a summary of it.

  • Any state's own income tax. No state pack is bound in this deployment, and the cap is a federal deduction limit, not what a state charges.
  • Residency, domicile, part-year allocation and reciprocity.
  • Pass-through entity tax workarounds, which are a state question.
  • Whether itemizing beats the standard deduction at all.

Where the figures come from

1 rules in the pack this server reads, each carrying its authority and legal effective date. The engines read from the pack, and a constant reappearing in the calculation path fails the build.

RuleAuthority
salt_capIRC 164(b)(6); OBBBA sec. 70120; IRS 2026 Form 1040-ES correction

Scripted case coverage

5 of the 71 console cases call this server over JSON-RPC on every build, across 1 of the 15 client objectives the case inventory groups by: What is deductible.

CaseWhat it asksWhat it showsOutcome
salt-full-capUnder the threshold: the full cap$40,400 of a $60,000 bill is deductible; the rest is simply lost and does not carry forward.completed
salt-phasing-downInside the phase-down rangeA slope, not a cliff: 30 cents per dollar of MAGI above the threshold. Income in this band costs more than its own marginal rate.completed
salt-at-the-floorPast the floorThe cap stops falling at $10,000 however high income goes, so the penalty on extra income ends there too.completed
salt-separate-filerMarried filing separately halves everythingCap, threshold and floor are all halved, which is easy to miss when comparing a joint and separate return.completed
salt-no-state-is-coveredAsking what California chargesNo state pack is bound, so no state's own tax is computed. The answer names what a state pack would have to contain.completed

Questions it answers

How much state and local tax can I deduct?

The federal cap phasing down at 30 cents per dollar of MAGI above the threshold, to a floor. Not a cliff. Nothing is required to start: every input has a declared default the result reports. Call calculate_salt_cap on taxagent-salt over MCP. Every result carries the method it used, the rule pack it was pinned to, what is still missing and whether coverage was complete, for a licensed professional to review.

Which states' own income tax can this compute?

Which states' own tax this deployment can compute, and what a state pack would have to contain. Nothing is required to start: every input has a declared default the result reports. Call calculate_state_coverage on taxagent-salt over MCP. Every result carries the method it used, the rule pack it was pinned to, what is still missing and whether coverage was complete, for a licensed professional to review.

What does this server know about state tax?

Which calculators taxagent-salt exposes, what it will not compute, and the rule pack its figures are pinned to. Nothing is required to start: every input has a declared default the result reports. Call get_salt_capabilities on taxagent-salt over MCP. Every result carries the method it used, the rule pack it was pinned to, what is still missing and whether coverage was complete, for a licensed professional to review.

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