server-types-runtime-only

A project rule stating where server connection types must live in a monorepo, a codebase containing multiple related packages.

In plain words
What is it for?
Use it when adding or changing `AgentUIServer`, chat, builder, catalog, or related server types. The canonical definitions belong in `assistant-ui-runtime`, while the UI package only re-exports them.
Why use it?
It prevents duplicate or conflicting type definitions between the runtime package and the UI package.

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/server-types-runtime-only
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 394 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 $0.00394
Opus 5 $0.00000 $0.00197
Sonnet 5 $0.00000 $0.00079
Haiku 4.5 $0.00000 $0.00039

Measured yesterday against content hash fafa598affb3, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

server-types-runtime-only 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 yesterday.

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/server-types-runtime-only.mdc · 37 lines

What it actually says

Server types — runtime is the sole owner

Canonical AgentUIServer / chat / builder / catalog port types live only in @truefoundry/assistant-ui-runtime (src/server/types.ts + events.ts).

Rules

  • packages/trueforge-ui/src/server/types.ts is the host-facing barrel: re-export only from @truefoundry/assistant-ui-runtime (prefer /server when avoiding root name collisions). Do not put hand-written server port/DTO interfaces there or elsewhere in this monorepo.
  • Hosts import types from @truefoundry/trueforge-ui only — they must not need the runtime package for types.
  • Need a new field/method on the contract? Change runtime server/types.ts first, publish/bump, then re-export — never fork the shape in the UI SDK.
  • React wiring may stay here (ServerContext, ShellModeContext, TrueForgeServerConfig). Those modules import runtime types; they do not redefine ports.
  • Host adapters (e.g. frontend harnessServer) widen via generics / intersections over runtime bases (SkillMount / McpServerMount stay opaque object).

Examples

// ✅
import type { AgentUIServer, ListResult } from './types.js';

// ❌ local duplicate
export interface AgentChatServer { /* ... */ }
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. yesterday First seen · 37 lines · 0 tokens per session scan A fafa598affb3

Subscribe to this mod's changes

server-types-runtime-only is a cursor rule published in the GitHub repository truefoundry/trueforge (4,935 stars, last pushed 2d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 394 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 2026-08-30.