<!-- adk-managed-skill -->
Using Lightning Base Components
Lightning Base Components (LBC) are the
web components shipped
by Salesforce. This skill routes an agent through the right decision sequence
so the final component choice is
as specific as possible and backed by
real API docs — not a hand-rolled reimplementation of something that already
exists.
When to Use This Skill
- User describes a UI need ("searchable dropdown", "record edit form",
"modal with footer") and asks which component fits.
- User is about to build a primitive (button group, combobox, toast) and
should be using LBC instead.
- User asks you to review LWC markup for LBC-related issues — specifically
overriding SLDS classes or restyling LBC internals.
- User needs the authoritative props/events/slots for a specific
tag.
Prerequisites
- Knowledge of which LBC namespace your org uses ( is the default
public namespace; some platforms expose or others —
the user's meta files will clarify).
- The skill ships authoritative API docs for every Lightning Base Component
in references/lightning-components.md.
Each component is a
# Component API Structure
block; grep for
**Name:** <camelCaseName>
(e.g. ) to jump to its
Properties / Methods / Events / Slots. Read this rather than relying on
cached knowledge — LBC evolves and the reference is the source of truth.
Workflow
Step 1 — Read the entire component index first
Open lightning-component-index.md
and scan all entries before making any selection. This is non-negotiable:
LBC's value comes from picking the most specialized component, and skipping
the scan leads to reinventing compound widgets out of primitives.
As you scan, compile a candidate list — every component whose description
touches any aspect of the use case. Do not filter or rank yet.
Step 2 — Narrow to the most specific fit per feature
Once the scan is complete:
- For each feature in the use case, select the most specific component
that covers it. Prefer a specialized compound (,
, ) over a generic primitive
(, ) when the specialized one covers
the scenario end-to-end.
- Avoid duplication: if already renders fields for a
record, do not pair it with unless you're
explicitly overriding behavior.
Step 3 — Share the shortlist and confirm
Present the final shortlist to the developer with a one-line rationale per
component. Wait for explicit confirmation before pulling full API docs. This
prevents the agent from burning context on components the developer has
already mentally ruled out.
Step 4 — Retrieve full API docs
Once confirmed, use the bundled helper to pull the exact API blocks — this
avoids ad-hoc grepping across a large reference:
bash
scripts/extract-component-docs.sh <camelCaseName> [<camelCaseName>...]
Convert
tags to camelCase (no
prefix):
- →
lightning-record-edit-form
→
- →
Each returned block has the same shape: Basic Information (tag, namespace,
type), Properties (name, type, default, description), Methods,
Events, Slots, and (where applicable) usage notes. This skill is about
picking the components; the bundled reference is about wiring them.
Step 5 — Produce integration guidance
Using the per-component reference, walk the developer through:
- The exact tag and required attributes.
- Which events to bind (, , , …) and what
the event payload contains.
- Any slots to fill (headers, footers, custom content).
- Known constraints from the component docs (e.g.
requires and for edit/view modes).
Step 6 — Respect LBC styling rules
Do not override SLDS classes on LBC internals. See
lbc-expert-guidance.md for specifics.
Common issues:
- Targeting or in the host component's CSS to
restyle an LBC — LBC ships inside a shadow root, so these selectors
either leak into sibling components or get stripped entirely. Use the
component's documented styling hooks (, etc.) instead.
- Wrapping an LBC just to mutate its internal markup. You can't — the
markup is hidden behind the shadow root. If the component doesn't expose
the slot/prop you need, that's a platform-level gap, not a restyling job.
Examples
Example — "I need a multi-select combobox with typeahead"
- Scan the component index end-to-end.
- Candidate list includes: , ,
.
- Shortlist: (the documented multi-select base
component). Rule out — its documented API is
single-select; it has no and no multi-select mode.
Flag that only fits if the values are record IDs.
- Developer confirms .
- Run
scripts/extract-component-docs.sh dualListbox
.
- Return the , , payload, and required label
props from the block's Properties / Events sections.
Example — "I'm going to write my own modal"
- Scan finds , ,
, .
- Shortlist is the 4 modal components.
- Confirm.
- Run
scripts/extract-component-docs.sh modal modalHeader modalBody modalFooter
→ full modal API (how to extend , the static
pattern, slotting the header/body/footer).
- Steer the developer away from rolling their own dialog.
Verification Checklist
Troubleshooting
- Grep for returns no match — name is wrong, or the
reference uses a different camelCase. Double-check against the component
index ( → ,
lightning-record-view-form
→ ,
→ ).
- Proposed component doesn't have the prop you expected — trust the
real API doc over memory. LBC evolves; cached knowledge lies.
- Developer resists the shortlist — don't skip Step 4. Still retrieve
the docs for the developer's preferred choice so they see the actual
trade-offs.
- Developer wants to restyle LBC internals — redirect to styling hooks
(see the LBC Expert reference). Refusing shadow DOM penetration is the
correct answer.