Decision API for AI applications

AI decisions that do the math.

Ask questions about your data. Get typed answers—including calculated amounts and dates.

Recorded demo

Watch aityx calculate a refund and deadline.

A customer asks to cancel a subscription. Watch System One use their account and request data to calculate the refund and deadline, then recalculate as the facts change.

Actual System One API results.

Jev questionsDecisionStateResult

Jev questionsOptional

Jev formatOptional. Leave empty to run the Decision alone.

{ "answer": { "type": "noul", "instructions": "Your question" } }

DecisionVisual☰ Fields{ } JSON Schema

LockedEdit

{
  "name": "Subscription cancellation refunds",
  "inputs": {
    "customer_intent": {
      "type": "cancel_refund|cancel_only|other",
      "desc": "What is the customer's request type?",
      "options": {
        "cancel_refund": "Cancellation with a refund requested.",
        "cancel_only": "Cancellation without a refund requested.",
        "other": "Any other request."
      },
      "from": "The customer's stated subscription request."
    },
    "plan_amount": {
      "type": "number >= 0",
      "desc": "What is the subscription plan amount in USD?",
      "from": "The stated subscription plan price."
    },
    "period_days": {
      "type": "number > 0",
      "desc": "How many days are in the subscription period?",
      "from": "The stated subscription period length."
    },
    "unused_days": {
      "type": "number >= 0",
      "desc": "How many subscription days are unused?",
      "from": "The stated number of unused subscription days."
    },
    "accepted_on": {
      "type": "date",
      "desc": "On what date was the request accepted?",
      "from": "The stated request acceptance date."
    },
    "refundable": {
      "type": "boolean",
      "desc": "Is the account refundable?",
      "from": "The stated account refundability."
    }
  },
  "decisions": {
    "request_type": {
      "desc": "Return the subscription cancellation request type.",
      "table": [
        [
          "customer_intent",
          "=> cancel_refund|cancel_only|other",
          "# why"
        ],
        [
          "cancel_refund",
          "cancel_refund",
          "The customer requests cancellation with a refund."
        ],
        [
          "cancel_only",
          "cancel_only",
          "The customer requests cancellation only."
        ],
        [
          "-",
          "other",
          "The request is neither cancellation option."
        ]
      ]
    },
    "refund_eligible": {
      "desc": "Determine whether the cancellation request is eligible for a refund. True only for cancel_refund when the account is refundable and unused_days is greater than zero; false otherwise.",
      "table": [
        [
          "customer_intent",
          "refundable",
          "unused_days > 0",
          "=> boolean",
          "# why"
        ],
        [
          "cancel_refund",
          "true",
          "true",
          "true",
          "A refundable account with unused days qualifies for the requested refund."
        ],
        [
          "-",
          "-",
          "-",
          "false",
          "At least one required refund condition is not met."
        ]
      ]
    },
    "refund_amount": {
      "desc": "Return the eligible prorated refund in USD, capped at the plan amount and rounded to two decimal places; return zero when ineligible.",
      "table": [
        [
          "refund_eligible",
          "=> number >= 0",
          "# why"
        ],
        [
          "true",
          "prorated_refund(plan_amount, unused_days, period_days)",
          "Prorate using unused days capped at the subscription period."
        ],
        [
          "-",
          "0",
          "An ineligible request receives no refund."
        ]
      ]
    },
    "deadline_days": {
      "type": "number",
      "desc": "Processing deadline offset in calendar days.",
      "expr": "7"
    },
    "processing_deadline": {
      "type": "date",
      "desc": "Return the processing deadline seven calendar days after accepted_on.",
      "expr": "accepted_on + duration(\"P\" + string(deadline_days) + \"D\")"
    }
  },
  "functions": {
    "prorated_refund": {
      "params": {
        "amount": "number",
        "unused": "number",
        "period": "number"
      },
      "returns": "number",
      "body": "decimal(amount * (if unused < period then unused else period) / period, 2)"
    }
  }
}

☷ Inputs 6⬡ Types 0

StateJSON

Decision only▶ Execute ⌘↵

Send: State + DecisionPOST /v1/systemone

{
  "customer_intent": "cancel_refund",
  "plan_amount": 60, "period_days": 30, "unused_days": 10,
  "accepted_on": "2026-10-21", "refundable": true
}

AnswersInputsRaw

Run to see answers

refund.js POST /v1/systemone

1async function getRefund(decision, state, apiKey) {2  const res = await fetch("https://api.aityx.ai/v1/systemone", {3    method: "POST",4    headers: {5      Authorization: `Bearer ${apiKey}`,6      "Content-Type": "application/json"7    },8    body: JSON.stringify({ decision, state })9  });10  if (!res.ok) throw new Error(`aityx ${res.status}`);11  const { answers } = await res.json();1213  return {14    amount: answers.refund_amount.number,15    due: answers.processing_deadline.date16  };17}18const refund = await getRefund(decision, state, apiKey);19console.log(refund);

Built by Aletyx, a team with nearly two decades of enterprise decision experience.Meet the team →

Why aityx

From “refund requested” to
“$20, due October 28.”

Return the request type, refund amount and due date together. Your application can use each answer directly.

Request type

choice

Cancel + refund

Cancellation with a refund requested.

Refund amount

number

$20.00

$60.00 × 10 unused days ÷ 30 days

Processing deadline

date

October 28

October 21 + 7 calendar days

Recorded results using this example’s refund policy.

See the API example

Use cases

Calculate refunds, credits, and claim deadlines.

Combine a message with the facts your application already has. Return what qualifies, the amount, and the date—in one response.

Subscription refunds

How much is the refund, and when is it due?

“Please cancel my subscription and refund the unused time.”

$60 plan · 10 of 30 days unused · accepted October 21 · refundable

Request: Cancel + refund
Refund: $20.00
Due: October 28

$60 × 10 ÷ 30. The example gives seven calendar days to process the refund.

Service credits

Does this outage qualify for a credit?

“Can we get a credit for last month’s outage?”

98.5% uptime · $200 monthly fee · unscheduled outage · claimed after 3 days

Credit rate: 25%
Amount: $50.00
Claim window: Within 30 days

The example credits 25% below 99% uptime: $200 × 25% = $50.

Expense claims

Is this expense within the limits?

“Dinner with two clients. Receipt attached.”

$184 for 3 people · expense March 2 · submitted April 12

Result: Needs review
Per person: $61.33
Submit by: April 1

$184 ÷ 3 is within the $75 limit. Submission misses the example’s 30-day window.

How it works

One endpoint. Three execution shapes.

Send a decision, Jev questions, or both to POST /v1/systemone. aityx executes locally when the facts already match, grades evidence with Jev when you ask, and feeds Jev answers into your rules when both are present.

Decision only

Execute your model.

Send your decision with matching structured facts. Get choices, calculated amounts and dates in milliseconds.

Jev only

Grade the evidence.

Send Jev questions with a message or other input. Get named probabilities, choices and scores as the result.

Jev + Decision

Grade, then decide.

Send both in one request. Jev supplies the uncertain facts; your decision returns the consolidated answer.

Get started

Build in the console, or use your own tools.

Define your decision by hand in the console editor. Or build the same JSON with your preferred tools and submit it to aityx.

Run the example.

Get a request type, a $20 refund and an October 28 deadline.

Run the example →

Build in the console.

Define the inputs, tables and calculations by hand in the console editor, then check and run them.

Build by hand →

Build with your own tools.

Use your preferred tools or code to build a decision model in the aityx format.

See the model format →

Using Jev? Combine its judgments with your aityx model to calculate amounts and dates.

See how they work together →

Pricing

One rate for every execution shape.

Decision-only, Jev-only and combined calls all use the same execution rate.

Decision only
decision + state
Your model on matching facts. No provider call.
Jev only
questions + state
Jev grades the evidence; its answers are the result.
Jev + Decision
decision + questions + state
Jev supplies the uncertain facts; your decision answers.

Prices in USD per 1 million tokens. Responses show token usage. Review settled charges in the console.

Integration questions

A few API details.

Are calculated answers repeatable?

Yes, with the same decision and identical validated facts. Jev grading can vary, so the receipt separates values supplied in state from values supplied by Jev and records the calculation.

Can I see how an answer was calculated?

Yes. The response includes input sources and calculations in an inline receipt. Keep it with the facts you submitted. You can also view the model as JSON or a diagram.

What if information is missing?

Local execution stops if a required matching fact is missing. Add a Jev question when a fact must be graded, and use thresholds in your decision to route uncertain cases for review.

Does every decision need AI?

No. Send your decision with matching structured facts for local execution. Add Jev questions only when a fact needs to be graded from text or other unstructured evidence.

Can I use Jev with aityx?

Yes. Send Jev questions alone, combine them with structured data and a decision in one call, or run Jev separately and pass its answers as facts. Read the Jev guide →

How do I create a decision model?

Define it by hand in the console editor, or build the same JSON with your preferred tools and submit it with your input. aityx validates and executes supplied decisions; it does not create them for you. See the model format →

Can I start from questions or a document?

Questions, yes: run them with Jev alone or with a decision. Documents are not uploaded to create a model; include relevant text as evidence in state and ask Jev questions about it.

Who is behind aityx?

Aletyx, a team with nearly two decades of enterprise decision experience.

Tech preview

Put calculated answers in your application.

Return the outcome, amount and deadline together, ready for your code to use. Sign up with your email. No approval needed.

Get started Talk to the team

AI decisions that do the math.

Watch aityx calculate a refund and deadline.

Use the amount and deadline in your code.

Try your own questions.

From “refund requested” to
“$20, due October 28.”

Request type

Refund amount

Processing deadline

Calculate refunds, credits, and claim deadlines.

How much is the refund, and when is it due?

Does this outage qualify for a credit?

Is this expense within the limits?

One endpoint. Three execution shapes.

Execute your model.

Grade the evidence.

Grade, then decide.

Build in the console, or use your own tools.

Run the example.

Build in the console.

Build with your own tools.

One rate for every execution shape.

Decision only

Jev only

Jev + Decision

A few API details.

Put calculated answers in your application.

AI decisions that do the math.

Watch aityx calculate a refund and deadline.

Try your own questions.

From “refund requested” to “$20, due October 28.”

Request type

Refund amount

Processing deadline

Calculate refunds, credits, and claim deadlines.

How much is the refund, and when is it due?

Does this outage qualify for a credit?

Is this expense within the limits?

One endpoint. Three execution shapes.

Execute your model.

Grade the evidence.

Grade, then decide.

Build in the console, or use your own tools.

Run the example.

Build in the console.

Build with your own tools.

One rate for every execution shape.

Decision only

Jev only

Jev + Decision

A few API details.

Put calculated answers in your application.

From “refund requested” to
“$20, due October 28.”