nika: v1
workflow:
  id: price-watch
  description: "Watch a product price, ping me when it drops below my target"

vars:
  product_api: "https://api.shop.example.com/v1/products/macbook-air"
  alert_below: 899

secrets:
  alerts_webhook:
    source: env
    key: ALERTS_WEBHOOK_URL
    egress:                       # sanction the one send · the secret IS the URL
      - to: "nika:notify"
        host_from_self: true

tasks:
  check:
    invoke:
      tool: "nika:fetch"
      args:
        url: "${{ vars.product_api }}"
        mode: jq
        jq: "."
    output:                           # named jq bindings over the raw response
      price: ".price"
      name: ".name"
    on_error:
      # Offline rehearsal · a sample ABOVE the target — the gate below
      # stays closed and the dry run ends green with the alert skipped.
      recover: { price: 949, name: "MacBook Air (offline sample)" }

  alert:
    with:
      price: ${{ tasks.check.price }}     # value edges · the named bindings cross the boundary here
      name: ${{ tasks.check.name }}
    when: ${{ with.price < vars.alert_below }}
    invoke:
      tool: "nika:notify"
      args:
        channel: webhook
        target: "${{ secrets.alerts_webhook }}"
        message: "Price drop · ${{ with.name }} is now ${{ with.price }} (target ${{ vars.alert_below }})"
        severity: info

outputs:
  price: ${{ tasks.check.price }}

{"a":{"graph_format":2,"workflow":"price-watch","nodes":[{"id":"check","verb":"invoke","tool":"nika:fetch","permits":["tool: nika:fetch"]},{"id":"alert","verb":"invoke","tool":"nika:notify","when":"${{ with.price < vars.alert_below }}","permits":["tool: nika:notify"]}],"edges":[{"from":"check","to":"alert","kind":"value"},{"from":"check","to":"alert","kind":"value"}]},"engine":"0.105.0"}

showcase · tier 1 · business

Price watch

Pulls one field from the shop API, compares it in CEL, pings your webhook. No model call anywhere.

Not everything needs an LLM. The engine alone is a robot you can already trust. · conformance-gated in nika-spec ↗ · re-proven at every push

The whole file

2 tasks · 2 waves · the plan falls out of the bindings, nothing is scheduled by hand.

t1-price-watch.nika.yamlsource

1nika: v12workflow:3  id: price-watch4  description: "Watch a product price, ping me when it drops below my target"56vars:7  product_api: "https://api.shop.example.com/v1/products/macbook-air"8  alert_below: 899910secrets:11  alerts_webhook:12    source: env13    key: ALERTS_WEBHOOK_URL14    egress:                       # sanction the one send · the secret IS the URL15      - to: "nika:notify"16        host_from_self: true1718tasks:19  check:20    ◆invoke:21      tool: "nika:fetch"22      args:23        url: "${{ vars.product_api }}"24        mode: jq25        jq: "."26    output:                           # named jq bindings over the raw response27      price: ".price"28      name: ".name"29    on_error:30      # Offline rehearsal · a sample ABOVE the target — the gate below31      # stays closed and the dry run ends green with the alert skipped.32      recover: { price: 949, name: "MacBook Air (offline sample)" }3334  alert:35    with:36      price: ${{ tasks.check.price }}     # value edges · the named bindings cross the boundary here37      name: ${{ tasks.check.name }}38    when: ${{ with.price < vars.alert_below }}39    ◆invoke:40      tool: "nika:notify"41      args:42        channel: webhook43        target: "${{ secrets.alerts_webhook }}"44        message: "Price drop · ${{ with.name }} is now ${{ with.price }} (target ${{ vars.alert_below }})"45        severity: info4647outputs:48  price: ${{ tasks.check.price }}49

nika inspect · engine 0.105.0 · vendored graph, never re-derived

2 declared edges · 2 waves · the plan falls out of the bindings

try itopen in the playground guidethe walkthrough · docs verbinvoke toolnika:fetch toolnika:notify