Scenario GPT Image

Overview

Every member of GPT Image, OpenAI's image family on Scenario, both generates and edits through one prompt, with referenceImages carrying the image to edit and an optional alpha mask for inpainting. Four members were live at authoring time: GPT Image 2.5 Flare (fast, everyday), GPT Image 2.5 Sunburst (precision: dense copy, diagrams, edits that must hold geometry), GPT Image 2, and GPT Image 1.5, the one member with a fidelity dial and ratio sizing. Discover members with search and treat model_schema_get as the contract: the family agrees on prompt and references and splits on sizing, quality tiers, and fidelity.

Connection and the core loop: see the scenario skill in this repo; model-agnostic image work: the scenario-image skill. If a sibling skill named here is missing from your available skills, ask the user to install it (npx skills add scenario-labs/skills --skill <name>); unattended, proceed from tool schemas and flag the gap.

Quick reference

Shared shape at authoring time: prompt (required, cap 32000 characters), referenceImages (an array even for one, up to 10), numOutputs (1 to 10 variations of one prompt), quality, and background (auto, opaque, transparent on every member). The splits:

Contract	2.5 Flare and Sunburst	GPT Image 2	GPT Image 1.5
Sizing	width and height, 16 to 3840 px	same	aspectRatio: auto, 1:1, 3:2, 2:3
Inpainting	mask PNG	mask PNG	no mask field
quality	auto, low, medium, high, xhigh, max	auto, low, medium, high	high, medium, low (default high)
Source fidelity	prompt wording only	prompt wording only	inputFidelity: high locks, low reworks

Routing: Flare and Sunburst share one contract and one price list, so the choice is speed against quality. OpenAI describes Flare as the small model, built for speed with image quality comparable to GPT Image 2, and Sunburst as the base model, with higher image quality than GPT Image 2: Flare for everyday work, Sunburst when accuracy beats speed (packaging copy, dense numbers, exploded diagrams, geometry-preserving edits). GPT Image 2's contract is the 2.5 contract minus the two top tiers, and it prices its high at their max, so new work starts on 2.5. GPT Image 1.5 earns its place for inputFidelity: "low", which reworks a reference instead of reproducing it (only the first five references keep the higher fidelity), and for 3:2 or 2:3 output without pixel math. Transparent cutouts are no longer a 1.5 exclusive.

Quality is the price dial

quality moves the price more than size does, and the same word does not price the same across members. At authoring time a 1024 square priced 2, 3, 12, 20 and 45 CU across low, medium, high, xhigh and max on both 2.5 members; GPT Image 2 priced low at 2, medium at 12 and high at 45; auto resolved to 12 on all three; a 3840 by 2160 max run on Flare came to 69 CU. dry_run=true the member you will run and read creativeUnitsCost; referenceImages, numOutputs, quality, and sizing all carry cost_impact, so re-estimate after touching any. xhigh or max on GPT Image 2 is a 400 ("Input quality must be one of the following values") even on a dry run. Tier choice: low for drafts, medium for everyday finals, high when small text or legends must stay legible, and xhigh or max only when the tier below left a specific requirement unmet within your latency budget: a higher tier does not guarantee a better result for every prompt.

Sizing on the pixel members follows OpenAI's published grid: each axis a multiple of 16, long edge at most 3840, aspect between 1:3 and 3:1, total pixels between 655,360 and 8,294,400, above 2560 by 1440 experimental. The schema enforces only the 16-step range and dry_run priced a 1000 by 1000 request without complaint, so hold to the grid yourself. Common picks: 1024 square (fastest), 1536 by 1024, 1024 by 1536, 3840 by 2160 for 4K.

Masks and transparency

The mask is a PNG the size of the first reference image, read through its alpha channel only: transparent pixels are edited, opaque pixels preserved, RGB white or black ignored without alpha. Export with transparency, never flattened, and convert a white-on-black mask's white region to transparent. OpenAI treats the mask as guidance rather than a hard edge: when a region must stay pixel-identical, composite the approved edit back over the original.

background: "transparent" works on every member at every tier. Two authoring-time observations: alpha peaks at 254, never 255, so a check for fully opaque pixels reads the whole subject as semi-transparent; and the color data under transparent pixels carries a halo, so any surface that drops alpha (JPEG flattening, a thumbnail without transparency, a viewer compositing on black) shows the cutout glowing. On white or a checkerboard it is clean. Prompt the cutout as a clean cutout with a crisp silhouette, fine edges and label text preserved, no halos, no restyling, then inspect the alpha channel at hair, glass, shadows, and object edges. Keep PNG or WebP and the alpha channel through every hop, previews and downloads included.

Prompting behavior

Position is weight: style, medium, subject, and mood open the prompt, then scene, details, lighting, and text, in natural sentences rather than tag lists. Name the intended use (ad, UI mock, infographic, key art) to set the polish level. For photorealism say "photorealistic" and name concrete texture (pores, fabric wear, material grain); for people, describe framing, gaze, and what the hands are doing. A detailed brief gets normalized, not embellished: augment only a generic prompt, and never add characters, brands, slogans, or left-right placement the request did not imply. Past roughly seven distinct requirements some quietly drop, so build a clean base, then one targeted change per edit, passing the previous output back as the next reference.

When editing, say "change only X", list what must survive, and repeat that list on every iteration; anything unmentioned is open to change. Not every input image is an edit target: references supplied for style or mood make the run a generation with references. Give each reference a role by index ("image 1 is the product, image 2 the palette"); unassigned references blur together. numOutputs yields variants of one prompt, which is what layout drafts of one brief are; distinct subjects need distinct runs.

Text inside the image: quote the exact copy, spell tricky words letter by letter, brief the layout (each element's zone, its size rank against the others, what stays empty), state type weight and case, say how many times the copy appears, and append "no extra words, no duplicate text". Prompts naming public figures are declined; describe an archetype instead. Complex prompts can run around two minutes: wait through jobs_wait rather than re-running.

Worked example: a product hero with headline text

1. search with target="models", query="gpt image", public=true. Read names rather than rank: new members rank below GPT Image 2 while their usage is young. Headline text wants Sunburst, e.g. model_openai-gpt-image-2-5-sunburst (a live hit at authoring time: re-discover each session).
2. model_schema_get with that id: quality allowed values, sizing bounds, mask presence, and defaults first.
3. upload_asset the product photo (see the scenario skill) for its asset id.
4. model_run with that model_id, dry_run=true, and parameters={"prompt": "Editorial product photography, soft daylight. The exact bottle from image 1 on brushed concrete, label, shape, and color preserved. Headline \"DRINK GREEN\" in bold sans-serif, centered, appears once, no extra words, no duplicate text.", "referenceImages": ["asset_x"], "width": 1536, "height": 1024, "quality": "low", "numOutputs": 3} for the draft price; then run it with wait=false and jobs_wait on the returned job id, re-called with pending_job_ids on timeout, never a second model_run.
5. asset_display the three drafts and pick a composition. Repeat step 4 with that prompt, quality: "high", numOutputs: 1, dry_run=true first: the tier change moves the price.
6. asset_display the final and proofread the rendered text before batching; asset_download to save.

Common mistakes

• Carrying xhigh or max to GPT Image 2 or 1.5: a 400 at validation; read allowed values off each member's schema.
• Routing cutouts to 1.5 by habit: every member takes background: "transparent"; 1.5 is for inputFidelity and ratio sizing.
• Carrying sizing across members: width/height on 2 and 2.5, aspectRatio on 1.5, never both.
• Leaving inputFidelity at its high default on 1.5 when you wanted reinterpretation: drop it to low and re-dry_run.