control-plane-descriptors

A design pattern for control-plane components—descriptions of families, database targets, adapters, drivers, and extensions—paired with their runtime instances. A descriptor records what a component is and how it connects to the system; an instance is the usable implementation.

In plain words
What is it for?
Use it when defining or implementing control-plane families, targets, adapters, drivers, or extensions. Each component should use the corresponding Control descriptor type and its required identifying properties.
Why use it?
It gives related components a consistent type shape and avoids mixing newer Control*Descriptor types with removed legacy types. This makes tooling and component discovery more predictable.

Cursor rule for Codex

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/prisma/prisma-next/control-plane-descriptors
Clone the repo
git clone --depth 1 https://github.com/prisma/prisma-next

Made for: Codex.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 1,125 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 92% copy Near-identical to another mod 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 $0.01125
Opus 5 $0.00000 $0.00562
Sonnet 5 $0.00000 $0.00225
Haiku 4.5 $0.00000 $0.00112

Measured 2d ago against content hash b6b5d1f1458e, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

control-plane-descriptors 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 2d ago.

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.

Origin

This is a copy

92% identical to control-plane-descriptors — 22 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/rules/control-plane-descriptors.mdc · 128 lines

How it starts

The opening of the file, as written. The whole thing — 128 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Control Plane Descriptors Pattern

Overview

Control plane components (families, targets, adapters, drivers, extensions) use a consistent descriptor + instance pattern defined in ADR 151. All legacy descriptor types have been removed and replaced with Control*Descriptor types.

Pattern: ControlDescriptor + ControlInstance

CRITICAL: Always use Control*Descriptor types. Legacy types (FamilyDescriptor, TargetDescriptor, AdapterDescriptor, DriverDescriptor, ExtensionDescriptor, ControlPlaneDriver) have been completely removed.

Descriptor Types

All control plane descriptors follow this pattern:

// Family descriptor
ControlFamilyDescriptor<TFamilyId, TFamilyInstance>

// Target descriptor
ControlTargetDescriptor<TFamilyId, TTargetId, TTargetInstance>

// Adapter descriptor
ControlAdapterDescriptor<TFamilyId, TTargetId, TAdapterInstance>

// Driver descriptor
ControlDriverDescriptor<TFamilyId, TTargetId, TDriverInstance>

// Extension descriptor
ControlExtensionDescriptor<TFamilyId, TTargetId, TExtensionInstance>

Required Properties

All descriptors must have:

  • kind: Discriminator ('family' | 'target' | 'adapter' | 'driver' | 'extension')
  • id: String identifier
  • familyId: Literal type (e.g., 'sql')
  • targetId: Literal type (e.g., 'postgres') - required for target, adapter, driver, extension
  • manifest: ExtensionPackManifest
  • create(): Factory method that returns an instance

Instance Types

Base instance interfaces:

  • ControlFamilyInstance<TFamilyId>
  • ControlTargetInstance<TFamilyId, TTargetId>
  • ControlAdapterInstance<TFamilyId, TTargetId>
  • ControlDriverInstance<TTargetId> (replaces ControlPlaneDriver)
  • ControlExtensionInstance<TFamilyId, TTargetId>

Note: FamilyInstance is retained for CLI command handlers that need the full method set (validateContractIR, verify, schemaVerify, introspect, emitContract, toSchemaView). It uses ControlDriverInstance internally.

Read the full file on GitHub · 128 lines

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. 2d ago First seen · 128 lines · 0 tokens per session scan A b6b5d1f1458e

Subscribe to this mod's changes

control-plane-descriptors is a cursor rule published in the GitHub repository prisma/prisma-next (420 stars, last pushed 7d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 1,125 tokens. A static security scan graded it A with 0 findings. It is 92% identical to control-plane-descriptors, differing in 22 lines, and is treated as a copy.