Axonpack
5

Axonpackendstheguessworkwhenthingsbreak.

Answers you and your agent can both read. Every request, error, log and stored value, captured on the device and copied out as structured JSON.

Read the docsView on GitHub5
npx expo install @axonpack/expo-devtools
NetworkConsolePerfStorageCrashes
  • GETpending
    feed?page=2

    https://api.acme.dev/v1/feed?page=2

    Fetch/XHRfetch
  • GET2000.23 s · 7:13:09 PM
    session

    https://api.acme.dev/v1/auth/session

    Fetch/XHRfetch426 B
  • GET2000.26 s · 7:13:06 PM
    avatar-6aa14cb34f8e.svg

    https://cdn.acme.dev/files/6842b36ba01eccee19a4…

    Imgfetch1.1 KB
  • GET4010.19 s · 7:13:04 PM
    me

    https://api.acme.dev/v1/me

    Fetch/XHRxhr88 B
  • POST2010.41 s · 7:13:01 PM
    orders

    https://api.acme.dev/v1/orders

    Fetch/XHRxhr2.3 KB
  • WS1017:12:58 PM
    live

    wss://api.acme.dev/live

    WebSocketws12 frames
HeadersPreviewResponseTiming
Search this bodyAaab.*

{error: true, status: 401, …}

code:"TOKEN_EXPIRED"

error:true

message:"Access token has expired"

retryAfter:30

request:{id: "8f2a…", method: "GET"}

id:"8f2a4c19b7"

method:"GET"

headers:{authorization: "Bearer …", …}

status:401

traceId:null

2

  • [Cart:service]

    config loaded

    {branchId: "69f1d0caec05e9", currency: "GBP", …}

    7:12:43 PM

  • [Checkout]

    session restored

    {userId: 8812, retry: false}

    7:12:44 PM

  • SYNC::: Error syncing queue job. false

    Error: No queue jobs to process.

    x137:12:49 PM

  • [Cart:task]

    event received

    {eventType: "EXIT", cartId: "8f2a4c19b7"}

    7:13:05 PM
Run an expression
MessageArgumentsSource
UNCAUGHT ERRORTypeError
Origin
CartScreen.tsx:42:11
Level
error
Repeated
13 times

{queue: "sync", pending: 0, …}

queue:"sync"

pending:0

lastRunAt:"2026-09-11T19:12:49.108Z"

error:null

StatisticsUser timingInteractions 51Long tasks 4
Frames per secondlast 5 min
JS thread56Main thread60
65330
5m ago2.5mnow
Interactions

3.13s

worst · 0.3 s average of 51

JS heap190.3MB
209.3 MB104.7 MB0 B
2m ago1mnow

of 236.0 MB allocated

Device memory24.0GB

0 B available to this app

InteractionsLong tasks
  • touchendhandler 1.1 ms0.1 s
  • touchendhandler 0.426 ms3.13 s
  • touchstarthandler 0.468 ms0.89 s
  • touchendhandler 2.3 ms0.11 s
  • touchendhandler 9 ms0.25 s
  • touchendhandler 1.4 ms0.12 s
  • touchstarthandler 3.4 ms0.27 s
  • touchendhandler 7.7 ms0.38 s
Async Storage 5
  • {}auth-user25.2 KB

    OBJECT{"state":{"user":{"createdAt":"2026-09-09T15…

  • Ttauth.token184 B

    STRING"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ…

  • 01onboarding.seen5 B

    BOOLEANfalse

  • {}feature.flags11.0 KB

    OBJECT{"newCheckout":true,"betaSearch":false,…

  • Ttcart.items20.5 KB

    STRING"[{\"id\":\"6a0c0d0943f19e4adbe31ac7\",\"qty…

ValueRawEditInfo
Key
auth-user
Store
Async Storage (Async)
Shown as
Object
Stored as
string
Size
25.2 KB (25784 characters)
Read
7:15:15 PM
Editable
yes
Deletable
yes
2
  • Error19:15:55

    Deliberate crash from @axonpack/expo-devtools (JS thread)

    Fatal JS error700
  • TypeError19:12:04

    Cannot read property 'id' of null

    Render error412
  • Unhandled rejection19:08:31

    Token refresh failed, 401

    Promise208
SummaryBreadcrumbs
FATAL JS ERRORError
Captured
2026-09-11 19:15:50
Thread
JS
  1. 0crashJsThreadindex.ts.bundle:393969:20
  2. 1crashindex.ts.bundle:393781:156
  3. 2_performTransitionSideEffectsindex.ts.bundle:60458:20
  4. 3_receiveSignalindex.ts.bundle:60413:43
  5. 4onResponderReleaseindex.ts.bundle:60266:30
  6. 5executeDispatchindex.ts.bundle:19912:17
  7. 6runnative

Libraries

Every library is released and documented on its own, and this list comes straight from npm. If it is here, it is installable today.

Expo Devtools

v3.4.0

Development Debugging tool for React Native

  • devtools
  • Devtool
  • react
  • expo
  • react-native

Recent releases

All 21 →
  • 3.4.0minor1 Oct 2026
  • 3.3.0minor28 Sept 2026
  • 3.2.0minor
3,716 downloadsMITnpm ↗

React Native Devtools Tab

v0.1.2

Put your own tab in React Native DevTools, with a two-way channel to the running app

  • react-native
  • devtools
  • metro
  • expo
  • debugging

Recent releases

All 3 →
  • 0.1.2patch28 Sept 2026
  • 0.1.1patch
  • 0.1.0minor17 Sept 2026
389 downloadsMITnpm ↗

React Pretty Print

v0.1.1

Interactive JSON tree for React and React Native — you supply the View and Text primitives

  • json
  • pretty-print
  • json-tree
  • react
  • react-native

Recent releases

All 2 →
  • 0.1.1patch28 Sept 2026
  • 0.1.0minor10 Sept 2026
446 downloadsMITnpm ↗

How they are built

The point of a foundation library is that you stop thinking about it. These are what keep them that way.

Small and focused

One package solves one problem. Nothing here grows into a framework that wants to own your app's structure.

Dependency-light

Adding a package should not add a supply chain. Where one needs a library you may already have, you hand it over rather than having it installed for you.

Independently published

Each package versions and ships on its own, with its own documentation. Installing one never drags in another.

Honest about limits

Every guide ends with what the thing cannot do, and why. A number that cannot be measured is not shown rather than invented.