11img

Identity & permanence layer over the ElevenLabs image API (/v1/flows/image), built on top of the official @elevenlabs/elevenlabs-js SDK — not instead of it.

The official SDK is a faithful, generated wire layer. What it does not give you, and what nothing else on npm or GitHub gives you either, is here.

Why

The image API has three sharp edges that every consumer re-implements by hand:

1. References are a tagged union you must build yourself — {type:"asset"}, {type:"generation"}, {type:"inline_base64"}.
2. Inline references are ephemeral. The API's own type documentation says an inline image "is stored as an ephemeral asset with no guaranteed retention: it may be deleted at any time after the generation completes."
3. There is no seed on the GPT and Gemini models (only Seedream has one), so visual consistency across a set of images cannot come from a seed.

11img answers all three: references coerce from anything, reused bytes are auto-promoted to persistent assets, and consistency comes from chaining a prior generation in as a reference.

Features

• Reference coercion — './hero.png' | 'https://…' | Buffer | 'gen_…' | 'asset:…' | '@name' | Generation all become valid wire references.
• Auto-promotion — the second time the same local bytes are used, 11img uploads them once as a persistent asset (11img:<hash>) and sends {type:"asset"} from then on. Measured: a 1.1M-character base64 payload disappears from every subsequent request.
• Named refs — refs add hero ./hero.png, then @hero anywhere. Recoverable on another machine with refs sync.
• The Generation entity — signed contentUrls expire; url() re-fetches when stale, save()/buffer() always download fresh. Persist gen.id, never the URL.
• Sessions — each turn chains the previous output in as a reference, which is what preserves identity in the absence of a seed. fork() branches from any point in the history.
• Batch with a content-addressed cache — the key is a hash of the exact wire request. Output bytes are cached, so a dead URL never costs you a frame, and interrupted runs journal their pending ids and resume without re-charging.
• Pre-flight validation — a runtime model registry rejects background on gpt-image-2, mask on Gemini, seed outside Seedream, an unsupported aspect ratio… before a single credit is spent, with an actionable hint.

Requirements

• Node ≥ 20.
• ELEVENLABS_API_KEY from a paid workspace (Pro or above). The free tier covers the web UI only; every image endpoint — including GET /v1/assets and the generation list — answers 402 paid_plan_required, "This endpoint requires a Pro plan or above."

SDK

import { ImgClient } from '11img';

const img = new ImgClient({ model: 'gpt-image-2', residency: 'eu' });

// one-liner
const hero = await img.generate({
  prompt: 'goalkeeper diving, cinematic',
  aspectRatio: '16:9',
  resolution: '2K',
});
await hero.save('out/hero.png');

// references of any shape
await img.generate({
  prompt: 'same player, far post header',
  refs: ['@hero', './kit-away.png', hero],
});

// iterative thread — each turn chains the previous output
const s = img.session({ defaults: { aspectRatio: '1:1' } });
const v1 = await s.gen('a minimal geometric owl logo, black on white');
const v2 = await s.gen('the same owl logo, now with a thin circular border');
const v3 = await s.fork(v1).gen('the same owl logo, in a rounded square badge');

// fire-and-forget, for a web backend
const job = await img.submit({ prompt: '…', webhook: 'all' });
await db.save(job.id);                  // later: await img.result(id).wait()

// batch — cached, resumable, bounded concurrency
const frames = await img.batch(
  scenarios.map(sc => ({
    key: sc.name,
    prompt: sc.description,
    refs: ['@hero'],
    aspectRatio: '16:9',
  })),
  { concurrency: 4, onProgress: p => console.error(`${p.done}/${p.total}`) },
);

CLI

11img "a goalkeeper diving, cinematic"                # → out/…png (path on stdout)
11img gen -p "same, far post" -r @hero -r ./kit.png --ar 16:9 --res 2K -q high
11img models                                          # the real API enum + capabilities
11img refs add hero ./hero.png                        # named persistent reference
11img refs ls | rm <name> | sync
11img batch frames.json -c 4                          # manifest = array of BatchItem
11img get <gen_id> -o .                               # rescue any generation by id
11img ls --status failed
11img gen -p "…" --dry-run                            # exact wire request, 0 credits

stdout carries only paths (or JSON with --json); progress and errors go to stderr, so 11img "…" | pbcopy just works.

Models

Nine models, from the real API enum — 11img models prints them with their capabilities. Highlights:

model	refs	mask	seed	resolution	notes
gpt-image-2	≤10	yes	no	1K/2K/4K	default; 15 aspect ratios; no background
gpt-image-1.5	≤10	yes	no	—	has background; sunset 2026-12-01
gpt-image-1	≤10	yes	no	—	sunset 2026-10-23
gemini-3-pro-image	≤10	no	no	1K/2K/4K
gemini-3.1-flash-image	≤10	no	no	512/1K/2K/4K	widest ratios (up to 8:1)
bytedance-seedream-5-*	≤10	no	yes	1K–3K	not available in the US

The models shown in the ElevenCreative web UI (Nano Banana, FLUX, Krea, Runway, Kling, Seedream 4.x) are not in the API enum.

State

Everything lives in .11img/ per project: refs.json (named + auto-promoted refs) and cache/ (batch outputs + resume journal). The API key is only ever read from ELEVENLABS_API_KEY — never written to disk.

Verified against the live API

Exercised end to end on 2026-08-16 against a paid workspace:

• generation, download, and the 402 path on a free key;
• an asset reference reproducing the source logo exactly inside a new composition;
• session chaining preserving identity across turns without a seed;
• auto-promotion: inline on first use → asset on the second → same asset on the third;
• batch cache: 26.5s cold → 1.0s warm at zero credits, and editing 1 of 2 items regenerating exactly 1.

Two places where the live API differs from its documentation:

• The generation list response carries id, status, content_url and content_mime_type only — not model_id, even though model_id is a valid filter parameter.
• Signed URLs are issued with X-Goog-Expires=7200 (2 hours), not the ~1 hour the docs state. 11img refreshes at 50 minutes, which is safe either way.

Ground truth

Model capabilities in src/models/registry.ts are derived by hand from the request types of @elevenlabs/elevenlabs-js@2.64.0. When bumping that dependency, re-diff the specs against the new api/types/*Request.d.ts.

License

MIT