Agent Skills: Agent Browser — Storybook component dev

Agent Browser — Storybook component dev

Inspect/debug one component at a time on a running Storybook, without the manager UI.

The key idea: hit the preview iframe, not the manager

Storybook serves two surfaces:

| URL | What renders | | ----------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- | | http://localhost:<port>/ | Manager — sidebar nav, toolbar, addons panel + the story | | http://localhost:<port>/iframe.html?id=<storyId>&viewMode=story | Preview iframe — ONLY the story canvas (with the package's global decorators: theme/font providers). No sidebar, toolbar, or addons. |

Always point agent-browser at the iframe URL. That answers "render only the current component" — the manager chrome is gone, you get just the component (plus whatever providers .storybook/preview wraps every story in, which you usually want).

viewMode=story = the single rendered story. viewMode=docs = the autodocs page. Use story.

Ports (Hydra packages)

| Package | Port | Start (Hydra root) | | ------------------ | ---- | ----------------------------------------------------- | | @aircall/ds | 6008 | pnpm sb:dev:ds (or cd packages/ds && pnpm sb:dev) | | @aircall/blocks | 6009 | pnpm sb:dev:blocks | | @aircall/aw-ui | 6007 | — | | @aircall/tractor | 6006 | — |

Storybook must already be running (long-lived). See aircall-hydra-ui-lib → rules/debug-blocks.md for the blocks dev-server workflow.

Finding the story ID

The id is slug(meta.title) + -- + slug(story name), where slug lowercases and replaces runs of non-alphanumerics with a single -. ⚠️ It does not split camelCase: Utilities/CopyButton → utilities-copybutton (NOT copy-button), story Icon Only → icon-only, so the full id is utilities-copybutton--icon-only.

Because of that camelCase gotcha, don't guess — list them from the server's manifest:

agent-browser open "http://localhost:6009/index.json"
agent-browser get text body            # JSON: { entries: { "<id>": { title, name, type } } }
# or fetch directly:
curl -s http://localhost:6009/index.json | jq '.entries | keys'

Filter to type == "story" (skip "docs" entries).

Workflow

Use a dedicated session so it doesn't collide with other browsing:

# 1. Open the isolated story
agent-browser --session storybook open \
  "http://localhost:6009/iframe.html?id=utilities-copybutton--left-icon-with-label&viewMode=story"

# 2. Wait for the story to mount, then snapshot
agent-browser --session storybook wait --fn "document.querySelector('#storybook-root')?.children.length > 0"
agent-browser --session storybook snapshot -i

# 3. Interact via @refs from the snapshot, re-snapshot after DOM changes
agent-browser --session storybook click @e1

# 4. Screenshot just the component
agent-browser --session storybook screenshot "#storybook-root" story.png

The mount point is #storybook-root (Storybook 7+). Scope to it to capture only the component. Mind the arg shapes — they differ between commands:

• screenshot [selector] [path] — selector is a positional arg, then the path: screenshot "#storybook-root" story.png. (There is no -s flag here; passing -s silently writes a file literally named -s.)
• snapshot -s "#storybook-root" — snapshot does take -s/--scope as a flag.

Dark mode / theme

Theme is a Storybook global (withThemeByDataAttribute, sets data-theme on the root, default light). Force it from the URL — no toolbar needed:

# dark
…/iframe.html?id=utilities-copybutton--left-icon-with-label&viewMode=story&globals=theme:dark
# light (default)
…/iframe.html?id=utilities-copybutton--left-icon-with-label&viewMode=story&globals=theme:light

(globals=key:value; multiple separated by ;.)

Debugging (the point of this skill)

agent-browser --session storybook console          # console.log/warn/error from the story
agent-browser --session storybook console --clear   # clear before reproducing
agent-browser --session storybook errors            # uncaught page errors / React throws
agent-browser --session storybook eval "getComputedStyle(document.querySelector('[data-slot=button]')).backgroundColor"
agent-browser --session storybook get styles @e1     # font/color/bg/spacing of an element
agent-browser --session storybook highlight @e1      # visually outline an element

Typical loop: reload story → console --clear → reproduce the interaction → errors + console to read what broke → inspect with get styles / eval.

Args / controls via the URL

Override a story's args without touching the toolbar:

…/iframe.html?id=utilities-copybutton--playground&viewMode=story&args=variant:ghost

Viewport

agent-browser --session storybook set viewport 1280 800

Cleanup

agent-browser --session storybook close

Troubleshooting

• Blank canvas — story still mounting; wait --fn "document.querySelector('#storybook-root')?.children.length > 0" or wait --load networkidle, then re-snapshot.
• 404 / "Story not found" — wrong id. Re-derive from index.json; confirm it's a story not a docs entry.
• Manager chrome still visible — you opened / or /?path=/story/.... Use /iframe.html?... instead.
• Connection refused — the dev server isn't running. Start it (pnpm sb:dev:blocks) and wait for "Storybook started".
• Theme won't change — confirm &globals=theme:dark (not ?theme=); it's a Storybook global, applied as data-theme on the root.
• Stale component state across reopens — re-opening in the same session can keep the previous render's interactive state (e.g. a CopyButton stuck on "Copied" after an earlier click), so a screenshot captures the wrong state. For a deterministic capture: reload the story first, or use a fresh --session, or wait for the reset state before shooting (e.g. wait --fn "/Copy$/.test(document.querySelector('[data-slot=button]')?.textContent)").

Related skills

• agent-browser — the full agent-browser command reference (snapshot refs, sessions, network, etc.).
• aircall-hydra-ui-lib — how to build & debug @aircall/ds / @aircall/blocks components; its debug-blocks rule starts the server and hands off to this skill.