nika:image_generate

A missing required arg is a nika check finding before anything runs; the vocabulary below comes from the binary itself (nika catalog --tools --json), not from prose.

provider

stringlocal | openai | gemini | xai | mock (inferred from model: when omitted · local is never inferred)

model

stringprovider model id · defaults: stablediffusion (local · LocalAI convention) · gpt-image-2 · gemini-3.1-flash-image · grok-imagine-image · mock-image-1

prompt*

stringthe creative brief the provider renders

mode

stringgenerate (default · text→image) | edit (source image(s) + instruction)

image

stringmode:edit · one source image PATH (read · permit-gated fs.read)

images

stringmode:edit · source image PATHS (multi-ref · capped per provider)

mask

stringmode:edit · optional pixel-mask PATH (openai/local only · refused elsewhere)

n

integervariant count 1..=10 (gemini runs n sequential calls)

aspect_ratio

string1:1 | 16:9 | 9:16 | 4:3 | 3:4 | 3:2 | 2:3 | 21:9

size

stringexact WIDTHxHEIGHT (gpt-image-2 arbitrary /16 sizes · gemini folds to a size class) or auto — an exact size wins over aspect_ratio

quality

stringauto (default) | low | medium | high | ultra (folds to high on openai · model-tier on gemini)

format

stringpng (default) | jpeg | webp — magic bytes are the authority on what lands

compression

integer0..=100 · jpeg/webp only (openai output_compression)

background

stringauto (default) | transparent (needs png/webp and a supporting model) | opaque

seed

integergemini best-effort · openai has no seed (warned + dropped)

reference_images

arraymedia roadmap — rejected loudly in V1

provider_options

objectvetted pass-through · openai {moderation, user} · gemini {thinking_level, image_size} · xai {user, resolution}

output_dir*

stringdirectory the assets land in (rides the declared permits.fs boundary)

filename_prefix

stringfilename stem (else metadata.page_slug, else `image`) — sanitized, traversal-free

save

booleanV1 contract: stays true — assets land on disk, never inline

manifest

booleanwrite the provenance manifest JSON beside the assets (default true)

metadata

objectfree provenance fields (campaign · page_slug · locale …) echoed to output + manifest

timeout_ms

integerper-request deadline · default 180000 · 1000..=600000

debug

booleanecho the sanitized raw provider response (base64 stripped)

67  render:68    with:69      brief_image_prompt: ${{ tasks.brief.output.image_prompt }}70    ◆invoke:71      tool: "nika:image_generate"72      args:73        provider: mock              # SLOT: local | openai | gemini | xai (local/mock first)74        prompt: "${{ with.brief_image_prompt }}"75        output_dir: "${{ const.out_dir }}"76        filename_prefix: "asset"    # SLOT: filename stem

a verbatim excerpt, real line numbers from media-asset-pack.nika.yaml, conformance-gated upstream on every spec push. open the full skeleton →

images, audio, charts: assets, not blobs.

• nika:chart
• nika:image_fx
• nika:image_generate
• nika:tts_generate