trueforge-ui-slots

Every newly created or newly JSX-bearing component in @truefoundry/trueforge-ui MUST be host-overridable through the slots system. Do not hard-import leaf UI into layouts/containers when a slot exists (or should exist).

Cursor rule for Cursor

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/truefoundry/trueforge/trueforge-ui-slots
Clone the repo
git clone --depth 1 https://github.com/truefoundry/trueforge

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 323 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00323
Opus 5 $0.00000 $0.00161
Sonnet 5 $0.00000 $0.00065
Haiku 4.5 $0.00000 $0.00032

Measured today against content hash 053d71fb244f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

trueforge-ui-slots scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured today.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/rules/trueforge-ui-slots.mdc · 44 lines

What it actually says

Slotted UI components (useSlot)

Every newly created or newly JSX-bearing component in @truefoundry/trueforge-ui MUST be host-overridable through the slots system. Do not hard-import leaf UI into layouts/containers when a slot exists (or should exist).

Checklist for a new / newly JSX component

  1. Export the component and augment AtomSlots in the same file:
declare module '../theme/SlotsProvider.js' {
  interface AtomSlots {
    MyComponent: typeof MyComponent;
  }
}
  1. Register the default in src/theme/defaultSlots.ts.
  2. Parents render it via useSlot('MyComponent'), never a direct import of the default implementation (except inside defaultSlots.ts).
  3. Keep the public prop surface stable so hosts can swap the implementation.

Examples

// ❌ BAD — layout hard-wires a leaf
import { AgentsLibraryButton } from '../atoms/AgentsLibraryButton.js';
<AgentsLibraryButton compact />

// ✅ GOOD — host can override
const AgentsLibraryButton = useSlot('AgentsLibraryButton');
<AgentsLibraryButton compact />

Primitives that are already slotted (Button, SearchInput, etc.) follow the same rule when exposed as named atoms; internal helpers with no JSX need no slot.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. today First seen · 44 lines · 0 tokens per session scan A 053d71fb244f

Subscribe to this mod's changes

trueforge-ui-slots is a cursor rule published in the GitHub repository truefoundry/trueforge (5,040 stars, last pushed today), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 323 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-02.