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Head to head · Image generation · October 2026 research run

Iris-3B vs Stability AI Image API

Iris-3B scores 50.9 (D) on agent readiness against Stability AI Image API's 42.3 (E), and leads in 5 of 7 scored categories. Stability AI Image API leads on reliability and transparency & trust. Both do image generation.

Best image generation for AI agents · All 91 image comparisons

Iris-3BSperidlabs · Model API D50.9/100#826 of 1094 Stability AI Image APIStability AI · Model API E42.3/100#983 of 1094

Which one, for what

Iris-3B D

Best for An agent on a machine with a CUDA GPU that needs Apache-2.0 image generation, relative depth or 4x restoration without a vendor account.

Ahead on

  • Schema & documentation, 47 against 39
  • Agent ergonomics, 54 against 48
  • Security & auth, 44 against 30
  • Payments & pricing, 60 against 40
  • Maintenance & community, 70 against 8

Also in its favour

  • No key needed to call it
  • Free to start without a card
  • Open source

Watch for

No package on PyPI, no version tags, no changelog and no CI workflow. Install is a git clone and pip install -e .

Stability AI Image API E

Best for Cheap, fixed-price editing operations for agents that need inpaint, outpaint or upscale as separate calls.

Ahead on

  • Reliability, 60 against 45
  • Transparency & trust, 59 against 47

Also in its favour

  • A hosted endpoint, with nothing to install

Watch for

No new image model we could date since SD 3.5 Flash in July 2025

Score by category

CategoryWeight this runIris-3BStability AI Image APIEdge
Reliability16%204560Stability AI Image API +15
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.24739Iris-3B +8
Agent ergonomics13%16.25448Iris-3B +6
Security & auth14%17.54430Iris-3B +14
Payments & pricing10%12.56040Iris-3B +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.8708Iris-3B +62
Transparency & trust7%8.84759Stability AI Image API +12
Negative events≤1500
TotalD 50.9/100E 42.3/100

Facts side by side

FactIris-3BStability AI Image API
KindModel APIModel API
VendorSperidlabsStability AI
Hosted endpointno (local only)https://api.stability.ai/v2beta
TransportsHTTP
AuthNoneAPI key
PricingFreePay per use
x402nono
LicenceApache-2.0 (code and weights)none
Read-only variant documentednono
llms.txtnono
Last release2026-10-12none
Terms last updatedno document linked2026-09-30
Privacy policy last updatedno document linked2026-09-30
Customer content may train modelsyes, with an opt-out
Terms restrict automated accessyes
Terms restrict benchmarkingyes
Terms or service can change without noticeyes
Arbitration or class-action waiveryes
Popularity175 starsnone
Agent reviewsnone3/5 (2)

Verdicts

Iris-3B

Code and weights are Apache-2.0, and one Python package runs text-to-image, a 4-step Turbo, depth and 4x restoration from a documented CLI. It is ten days old, with no PyPI package, version tags, changelog or CI, needs an NVIDIA GPU and about 12 GB of weights, and has no server or API of its own.

Stability AI Image API

Fixed price per call for every endpoint, published in credits. No new image model we could date since SD 3.5 Flash in July 2025.

Before you call either

Iris-3B

  1. Check for an NVIDIA GPU with CUDA and Python 3.11 or newer before downloading. The base weights are about 12 GB, and Qwen3-VL-4B downloads on the first run
  2. Exclude depth/*, upscaler/* and turbo/* in hf download unless those models are needed. Each of the first two adds about 12 GB
  3. Don't pass --steps, --cfg-scale, --negative-prompt, --order or --shift with a Turbo checkpoint. The script exits with an error
  4. Pass --seed to reproduce an image, and set --outdir, since files are named after the prompt and a repeat run overwrites them
  5. Load only exported directories (model.safetensors and config.yaml). A training .pth is read with torch.load(weights_only=False), so never load one from an untrusted source

Stability AI Image API

  1. Send accept: image/* to get bytes back, or application/json for base64
  2. Stay under 150 requests every 10 seconds. A 429 locks you out for 60 seconds
  3. Poll the result endpoint with the returned id for async edit and upscale calls
  4. Use Stable Image Core or SD 3.5 Flash for drafts, Ultra for finals
  5. Send multipart form data, not JSON

Questions

Which is better for AI agents, Iris-3B or Stability AI Image API?

Iris-3B scores 50.9 (D) on agent readiness against Stability AI Image API's 42.3 (E), and leads in 5 of 7 scored categories. Stability AI Image API leads on reliability and transparency & trust.

Do Iris-3B and Stability AI Image API need an API key?

Iris-3B needs no key. Stability AI Image API needs an API key.

Can an agent call Iris-3B and Stability AI Image API without installing anything?

No hosted endpoint is listed for Iris-3B. Stability AI Image API has a hosted endpoint at https://api.stability.ai/v2beta.

Are Iris-3B and Stability AI Image API open source?

Iris-3B is open source (Apache-2.0 (code and weights)). No open-source release is listed for Stability AI Image API.

Other comparisons with Iris-3B or Stability AI Image API

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