Every agentic-report technique, told through one station network

What Kestrel measures

Every ten minutes the stations report windgustsrainpressure to the harbour page.

A volunteer adds a station with one command, kestrel add K6 --site new-breakwater, and the harbour master asked the network for one thing: to warn of a gale before it reaches the moles.

:::lead
Every ten minutes the stations report :swap[wind]{words="gusts, rain, pressure"} to the harbour page.
:::

A volunteer adds a station with one command, :typing[kestrel add K6 --site new-breakwater], and the
harbour master asked the network for one thing: to warn of a :term[gale]{key="gale"} :mark[before]{shape="underline"}
it reaches the moles.

:::glossary{key="gale" term="Gale" forms="gales"}
Wind of force 8 on the Beaufort scale: a mean speed of 34 to 40 knots.
:::

Six stations, read from one export

The export taken September 20, 2026 at 09:00 AM GMT+1 lists 6 stations. The card is written once, and the build repeats it for every station in data/network.json.

Source: Kestrel export, 106,240 reports from 6 stations · September 20, 2026 at 09:00 AM GMT+1

The frontmatter names the file, and expect fails the build if the export stops listing six stations. A placeholder that names the page data is filled inside code blocks as well, so the listing below leaves out the source line and keeps to the repeated card, whose s is not a data name.

---
data:
  - data/network.json
---

::expect{data="network.stations" count="6"}
::expect{data="network.stationCount" equals="6"}

:::::cards{title="Stations"}
::::each{in="network.stations" as="s"}
:::card{title="{{s.code}} · {{s.site.en}}" status="{{s.card}}"}
{{s.note.en}}; {{s.uptime}}% of the expected reports arrived this season.
:::
::::
:::::

The roster becomes cards on a phone

Each row of the roster is read on its own, so layout="stack" turns every row into a card on a narrow screen, with the column headers as labels. On a wide screen it stays a table.

:::table{layout="stack"}

| Station | Site             | Mast height | Sensors                 |
| ------- | ---------------- | ----------- | ----------------------- |
| K1      | North mole       | 8 m         | wind, gusts, pressure   |
| K2      | Lighthouse point | 24 m        | wind, gusts, visibility |
| K3      | Fish quay        | 6 m         | wind, rain              |
| K4      | Dune school      | 12 m        | wind, rain, temperature |
| K5      | Coastguard hut   | 18 m        | wind, pressure          |
| K6      | New breakwater   | 7 m         | wind, swell             |

:::

A day of wind, wider than the column

On 18 September the mean wind at K2 rose from 15 to 38 knots and fell back by night. K5 is missing: it has been silent since the storm of 14 September. The readings are compared across rows and hours, so the table keeps its grid with layout="scroll". On a phone it scrolls sideways with the station code held in place, and Open shows it full screen; the same control opens any diagram or chart wider than its column.

Source: Kestrel export, mean wind in knots every two hours, five stations reporting · September 18, 2026

::::table{layout="scroll"}
:::each{in="network.day.rows" as="r"}

| Station    |     00:00 |     02:00 |     04:00 |     06:00 |     08:00 |     10:00 |     12:00 |     14:00 |     16:00 |     18:00 |     20:00 |     22:00 |
| ---------- | --------: | --------: | --------: | --------: | --------: | --------: | --------: | --------: | --------: | --------: | --------: | --------: |
| {{r.code}} | {{r.h00}} | {{r.h02}} | {{r.h04}} | {{r.h06}} | {{r.h08}} | {{r.h10}} | {{r.h12}} | {{r.h14}} | {{r.h16}} | {{r.h18}} | {{r.h20}} | {{r.h22}} |

:::
::::

The source lines under this table and under the chart below name the page data, so their listings leave them out.

Reports per month, counted from zero

The network opened in April with three stations and had six by September, so the growth of the monthly count is the news of the season. count-up grows the bars from zero when the chart comes into view; with reduced motion they stand at their values.

Source: Kestrel export, 106,240 reports in the season · September 20, 2026 at 09:00 AM GMT+1

::::::chart{title="Reports received per month" description="Ten-minute reports that reached the Kestrel server in each month of the 2026 season; September counts its first 20 days." type="bar" x-label="Month, 2026" y-label="Reports" count-up="true"}
:::::series{label="Reports"}
::::each{in="network.months" as="m"}
::point{label="{{m.label.en}}" value="{{m.reports}}"}
::::
:::::
::::::

The season, date by date

::::timeline{title="Kestrel season 2026" description="When each station joined and when the storm silenced K5."}
:::event{date="3 April 2026" title="The network opens with K1, K2 and K4" kind="success"}
Three stations report to the harbour page from the first day.
:::
:::event{date="12 September 2026" title="K6 joins on the new breakwater" kind="success"}
Mounted in the scroll-scene chapter below, it is the sixth station.
:::
:::event{date="14 September 2026" title="The storm silences K5" kind="warning"}
K5 stops reporting; a volunteer will reach it when the sea calms.
:::
::legend-item{event="success" label="stations join"}
::legend-item{event="warning" label="a station goes silent"}
::::

The listing leaves out two of the five events; they are written the same way.

Firmware 2.4 went back twice

The release stands at Steps: Plan (done) → Build (done) → Field test (in review) → Ship (not started); returned from Field test to Build 2 times.. The field test on K3 sent the build back twice, both times for salt in the anemometer bearing. Each node carries its status, which reads without colour too, and «×2» on the connection says how many times the return happened.

The release stands at :process[Plan > Build > Field test > Ship]{current="Field test" returns="Field test>Build×2"}.

:::diagram{title="Firmware 2.4 on its way to the stations" description="Plan and build are done; the field test on K3 returned the build twice and is running a third time; the radio approval came back once; shipping waits for both." layout="right"}
::node{id="plan" label="Plan" status="done"}
::node{id="build" label="Build" status="done"}
::node{id="field" label="Field test" detail="K3, fish quay" status="review"}
::node{id="radio" label="Radio approval" status="returned"}
::node{id="ship" label="Ship to stations" status="pending"}
::edge{from="plan" to="build"}
::edge{from="build" to="field"}
::edge{from="build" to="radio"}
::edge{from="field" to="build" label="salt in the bearing" count="2"}
::edge{from="field" to="ship"}
::edge{from="radio" to="ship"}
:::

Inside the Kestrel server

Readings travel from the stations through one radio gateway to the Kestrel server. The server is a small flow of its own, so the diagram carries a zoom: while the diagram is pinned, the camera flies into the server node and its inside grows readable in its place. Without motion the two drawings stand side by side.

::::diagram{title="From station to harbour page" description="Stations send readings through the radio gateway to the Kestrel server, which publishes the harbour page and keeps the archive."}
::node{id="stations" label="Six stations"}
::node{id="gateway" label="Radio gateway"}
::node{id="server" label="Kestrel server"}
::node{id="page" label="Harbour page"}
::node{id="archive" label="Archive"}
::edge{from="stations" to="gateway" label="every ten minutes" kind="data"}
::edge{from="gateway" to="server" label="readings" kind="data"}
::edge{from="server" to="page" label="publishes"}
::edge{from="server" to="archive" label="stores"}
:::zoom{node="server" title="Inside the Kestrel server"}
::node{id="intake" label="Intake"}
::node{id="check" label="Quality check"}
::node{id="publish" label="Publisher"}
::edge{from="intake" to="check"}
::edge{from="check" to="publish"}
:::
::::

A gale warning, played

At 14:00 on 18 September the lighthouse station measured a mean wind strong enough for a gale warning. The scene below plays the four log lines of that minute one by one; each beat lights its line, and the play button starts it again.

14:00:00  K2 lighthouse point  mean 38 kn  gust 44 kn
14:00:02  K2 logger            mean above 34 kn, flag GALE
14:00:05  server               GALE confirmed by K1, gust 41 kn
14:00:06  harbour page         gale warning shown for the moles

::::::demo{title="Gale warning, 18 September, 14:00" play="time" seconds="3"}

```text
14:00:00  K2 lighthouse point  mean 38 kn  gust 44 kn
14:00:02  K2 logger            mean above 34 kn, flag GALE
14:00:05  server               GALE confirmed by K1, gust 41 kn
14:00:06  harbour page         gale warning shown for the moles
```

:::beat{title="Reading" lines="1"}
K2 measures a mean of 38 knots, gusting to 44, at the lighthouse point.
:::

:::beat{title="Flag" lines="2"}
The station logger marks the reading as a gale.
:::

:::beat{title="Confirmation" lines="3"}
The server waits for a second station before it believes one reading.
:::

:::beat{title="Warning" lines="4"}
The harbour page shows the warning six seconds after the reading.
:::
::::::

Station K6 comes online

How the scroll scene is written

The section above carries scene="scrub": the diagram stays on screen while the scroll plays three beats, and each beat lights the nodes it names. A phone shows the diagram above the caption, one screen per beat.

::::section{title="Station K6 comes online" id="mount" nav="Scroll scene" scene="scrub"}

:::diagram{title="K6 joins the network" description="The sensors and logger of K6 and the Kestrel server." layout="right"}
::node{id="mast" label="Mast and sensors"}
::node{id="logger" label="Logger"}
::node{id="server" label="Kestrel server"}
::edge{from="mast" to="logger" kind="data"}
::edge{from="logger" to="server" kind="data"}
:::

:::beat{title="Mast up" focus="mast"}
Volunteers raise a 7-metre mast on the new breakwater and fit the wind and swell sensors.
:::

:::beat{title="Logger paired" focus="logger"}
The logger pairs with the radio gateway on the lighthouse point.
:::

:::beat{title="First reading" focus="logger, server"}
On 12 September the first reading from K6 reaches the server.
:::

::::

Where the stations stand

The map is drawn twice, on a light sea and on a dark one, and dark names the second file: the reader sees the variant of the scheme the page is in, and the scheme toggle switches it live. spotlight puts a loupe over the harbour, where three stations stand close together.

:::spotlight{x="31" y="42" zoom="1.5" title="Three stations guard the harbour"}
![Map of the Kestrel coast with stations K1 to K6](assets/coast.svg){dark="assets/coast-dark.svg"}

K1 on the north mole, K6 on the new breakwater and K3 at the fish quay stand a few hundred metres apart, so
a gust at the harbour mouth reaches all three within a minute.
:::

The season in four screens

One source takes one layout, and this guide is a document. The companion page the Kestrel season in four screens says layout: screens in its frontmatter, and one wheel turn, swipe or key press moves exactly one screen. The clip below records a reader flipping through it; from names the film that agentic-screencast web wrote, with its encodings and poster, and dark-poster gives the first frame as it looks in the dark scheme.

---
title: The Kestrel season in four screens
layout: screens
progress: nodes
theme: kestrel-theme.yaml
---

::video{from="assets/film" dark-poster="assets/season-poster-dark.webp" caption="The four-screen companion page, recorded as a reader flips through it."}

The first block shows the layout lines of the frontmatter of screens.md, without its description, language and localizations; the video line belongs to this page.

The season briefing, as slides

A document can carry a few slides of its own. The harbour meeting gets the season in three slides; they are part of this page, built with it, and open on the whole screen with the button under them.

:::::deck{title="Kestrel season briefing" id="briefing-deck"}
::::slide

## Six stations, one season

Every ten minutes, from April to September.
::::

::::slide{transition="push"}

## What went wrong

:::appear
Firmware 2.4 went back twice.
:::

:::appear{effect="fade"}
K5 fell silent after the September storm.
:::

:::notes
Say that no storm warning was missed.
:::
::::

::::slide{transition="zoom"}

## Next season

Two more stations on the north pier.
::::
:::::

A slide that holds appear steps or notes takes a longer fence than they do, and the deck a longer one still. #briefing-deck/2 opens the second slide.

Colours from the brand

Kestrel's colours are the chestnut back of the bird and the slate of its head. agentic-report theme took the two colours, kept their hue, moved their lightness until every contrast pair passes in both schemes, and wrote the theme file this page uses. The chestnut became the accent, the slate the eyebrow colour; in the dark scheme the link colour moved one step lighter.

agentic-report theme --colors "#b0532c,#4a6a8a" --extends daylight --output kestrel-theme.yaml

name: kestrel-theme
extends: daylight
colors:
  light:
    accent: '#b0532c'
    accentStrong: '#b0532c'
    accentSoft: '#ffe9e1'
    accent2: '#4a6a8a'
  dark:
    accent: '#b0532c'
    accentStrong: '#c76841'
    accentSoft: '#411e0f'
    accent2: '#6081a2'

The listing leaves out the comment line and the description, palette, focus and chart1 lines of the file; the page names it in its frontmatter as theme: kestrel-theme.yaml.

Calibration notes, for those who need them

Most readers need only the result of a calibration; the volunteer who services a mast needs the method. The method stays behind a disclosure, and the two sensors that differ get a tab each.

:::disclosure{title="How a Kestrel anemometer is checked"}
A volunteer compares the station against a hand anemometer held at the same height for ten minutes. A
difference above 2 knots sends the sensor to the bench.
:::

::::tabs{title="Sensor checks"}
:::tab{label="Wind"}
Once a season, and after every storm: the cups must spin freely and the bearing must be free of salt.
:::
:::tab{label="Rain"}
Once a month: the funnel is cleared of sand and the tipping bucket is tested with a measured litre.
:::
::::

The chapter list at the top of the page is ::contents on a line of its own; the build writes it from the chapter titles, and each nav label names the chapter in the side contents.

What changed since the last edition

Volunteers read the service notice for K3 twice: before the second field test and after it. The second edition is built with --since and the first edition, so the page marks what changed: inserted and removed words, a removed block left as a collapsed ghost, a changed code line, and a «Changes» list with a switch to hide them.

agentic-report build edition-1.md --output notice.html
agentic-report build edition-2.md --output notice-2.html --since notice.html

This page cannot show the change layer on itself: an example is built from its source alone, without a previous edition. The public site builds the notice both ways, so the pair can be opened side by side: the first edition and the second edition with its changes. Their sources, edition-1.md and edition-2.md, lie beside this page.