skills: note that DSpark/DFlash 2 are MLX drafter modes, not a third engine.

Keep the two-family decision rule. A better drafter can raise short-context
decode and still does not cancel the long-context KV-verify crossover. The
one-engine memory rule also applies on a 64 GB machine.

Author: VladimirBrejcha

README.md

@@ -22,7 +22,8 @@ The global baseline supports Codex and Claude Code and contains these 38 skills:
   skills from `rorkai/app-store-connect-cli-skills`
 
 Install the global baseline from this repository and it becomes available to
-agents on the machine. `local-model-serving` guides engine selection and the
+agents on the machine. `local-model-serving` guides engine selection (MLX
+spec-decode vs llama.cpp; drafters are MLX modes, not a third engine) and the
 one-engine-at-a-time memory rule for local LLM work; see its `SKILL.md`.
 
 Install or reconcile it from a checkout of the desired repository revision:

local-model-serving/SKILL.md

@@ -26,13 +26,22 @@ Both are OpenAI-compatible (`/v1/chat/completions`), so the same client code
 works against either — only the base URL and the thinking-off parameter
 differ.
 
+Drafters (DSpark, DFlash 2, and similar speculative-decoding heads) are
+**modes of the MLX family**, not a third engine. Do not install NVIDIA-only
+stacks (SGLang, vLLM) or a third MLX GUI to A/B a drafter. A better drafter
+can raise short-context decode; it does not remove the long-context
+crossover, because every verify round still walks the full KV. Use the
+drafter the local serving policy or helper names. llama.cpp may be LM Studio
+or `llama-server`; that is still the same family.
+
 ## First: The Memory Rule (crash prevention)
 
 **Never run both engines with a model resident at the same time.** On a
 128 GB machine, two resident 28 GB models plus the OS drove the system into
 ~20-46 GB of swap and crushed both engines' throughput (a long run was
-aborted, another finished at half speed). Each engine fits alone; both do
-not.
+aborted, another finished at half speed). The same exclusivity rule applies
+on a 64 GB machine that can fit only one ~28 GB model. Each engine fits
+alone; both do not.
 
 - Stop the other engine before starting one:
   `lms unload <identifier>` / `lms unload all`, or