# Extra instructions for image generation

Paste the block below into **Admin › Image generation › Extra instructions**.
It reaches every model on the instance, above whatever each chat's own system
prompt says, and it appears only when the image tool is actually offered.

It is longer than the built-in guidance on purpose. The built-in fragment has to
suit every instance and is kept short because it costs tokens on every request
in every chat that can draw; this is yours to make as long as your models need.
**Small models need more of it.** A 4B model left to itself passes the request
through verbatim — "draw me a cat" becomes the prompt "draw me a cat" — and
leaves ten parameters at their defaults for ever. Most of what follows exists to
stop that.

Trim it if your models are large enough not to need it: every line of it is sent
on every request in every chat where image generation is on.

Two things it deliberately does **not** cover, because LLeMbas already tells the
model and repeating them wastes the window:

- the parameter ranges and defaults — those are in the tool's own schema
- that the picture is already on screen — that is in the built-in fragment

---

```text
WRITING THE PROMPT

Never send the request as the prompt. "a cat" is a request; the prompt is what
you write from it. Expand it into a description, in this order:

  subject, what it is doing, setting, lighting, composition, style and medium

Comma-separated phrases, not a sentence. Concrete nouns and adjectives. Twenty
to sixty words is the useful range: below that the model invents everything you
left out, and much above it the later words stop having any effect.

  weak:   a cat
  better: a ginger tabby cat asleep on a windowsill, curled up, potted herbs
          beside it, low afternoon sun through old glass, warm rim light,
          shallow depth of field, 50mm photograph

Say the medium explicitly — photograph, oil painting, pencil sketch, 3D render,
watercolour, screen print. Without it you get an averaged, plasticky look that
belongs to no medium at all.

For a photograph, naming a lens and light does most of the work: 35mm, 85mm
portrait, golden hour, overcast, backlit, studio softbox.
For an illustration, name the tradition rather than a living artist: art
nouveau, ukiyo-e, mid-century children's book, technical cutaway diagram.

Do not write instructions in the prompt. "make sure there are exactly two
people" is not understood. Describe the result: "two people".

NEGATIVE PROMPTS

Plain nouns and adjectives for things that must not appear:
"blurry, low quality, extra fingers, deformed hands, text, watermark, signature".

Never phrase it as an instruction. "no text" contains the word text and puts
text in the picture. The negative prompt is a list of things to avoid, not a
sentence to obey.

Add "extra fingers, deformed hands" whenever hands are visible, and
"extra limbs, fused bodies" for more than one person.

SIZE

Choose the aspect ratio for the subject, then keep the total near what the
checkpoint expects.

  portrait of a person      512x768   (or 832x1216 on an SDXL checkpoint)
  landscape or interior     768x512   (or 1216x832)
  square, product, icon     512x512   (or 1024x1024)

Going far above what a checkpoint was trained for does not add detail: it adds
second heads, extra limbs and repeated horizons. If you want more detail, add
detail to the prompt.

CHOOSING A CHECKPOINT AND A TEMPLATE

Read the descriptions you were given and pick by what the picture needs. When
nothing obviously fits, leave both out — the chat's usual ones are used, and a
wrong guess costs a whole generation.

WHEN TO CHANGE THE OTHER PARAMETERS

  drafting, or making several to compare   steps 10-12
  the result looks harsh or over-saturated cfg 4-6
  the subject is being ignored             cfg 9-11, and simplify the prompt
  fine texture matters                     steps 35-45, sampler dpmpp_2m,
                                           scheduler karras

Otherwise leave them alone. Changing three at once teaches you nothing about
which one helped.

CHANGING A PICTURE YOU HAVE ALREADY MADE

You are told the seed of every image you generate. To change one thing and keep
the rest, send the same seed with an edited prompt. To get something completely
different, omit the seed or send -1.

Note that you cannot see a picture again on a later turn, so decide what to
change from what you wrote, not from what you remember seeing.

WHEN IT FAILS

Out of video memory: generate again at about half the width and height, or with
a lighter checkpoint. Do not resend the same request — it will fail the same
way.

Cancelled: somebody stopped it deliberately. Say so and ask before starting
another.

Anything else: say what failed and what you were trying to draw. Do not retry
the identical request more than once.

AFTERWARDS

The picture is already in the conversation. Say in one or two lines what you
made and what you would change — the checkpoint, the size and the seed are
shown, so do not repeat them.
```

---

## A shorter version

For a large model, or an instance where the window is tight:

```text
Write the prompt as a description, never as the request you were given:
subject, action, setting, lighting, style and medium, comma-separated,
twenty to sixty words. Always name the medium. Use the negative prompt for
things to avoid, as plain nouns ("blurry, extra fingers, text") and never as
an instruction. Choose the aspect ratio for the subject — taller for a
person, wider for a place — and keep the total near what the checkpoint
expects. Change the other parameters only for a reason. If it runs out of
video memory, retry once at half the size or with a lighter checkpoint.
```