Model Selection

By default, NinjaCat Agents are driven by Claude Sonnet 4.5, Anthropic's best model for complex agents and coding. However, depending on your Agent’s specific needs—whether for faster response times or enhanced reasoning—you can choose an alternative model.

NinjaCat will adjust the default model when newer, better models come out after spending time testing that the output is as good or better than the prior default, and if it is more cost efficient. When the default is changed, it only impacts brand new Agents. Users will need to adjust the model for existing Agents if they would like to. NinjaCat will not adjust the model for existing agents to avoid disrupting an already perfectly crafted Agent (sometimes a model change could require tweaks to the prompt).

Available Model Options Supported Today in NinjaCat

Anthropic Models

Model

Release date

Context Window

Input $ / 1M

Output $ / 1M

Positioning / Notes

Claude Opus 4.5

Nov 2025

~200K

~$5

~$25

Latest Anthropic flagship; strongest reasoning/coding at improved cost

Claude Sonnet 4.5
(Default Model for all new Agents)

Sep 2025

~200K

~$3

~$15

Best-balanced Claude
This is the default model for all new NinjaCat Agents

Claude Haiku 4.5

Oct 2025

~200K

~$1

~$5

Fastest & cheapest Claude

Claude Sonnet 4

May 2025

~200K

~$3

~$15

General-purpose Claude 4

Claude 3.7 Sonnet

Feb 2025

~200K

~$3

~$15

Transitional model between Claude 3 and 4; introduced hybrid reasoning improvements


OpenAI Models

ModelRelease date (Month Year)Context WindowInput $ / 1MOutput $ / 1MPositioning / Notes
GPT-5.2Oct 2025~400K~$1.75~$14Latest flagship, strong reasoning + long context
GPT-5.1Sep 2025~400K~$1.25~$10Improved efficiency over GPT-5
GPT-5Aug 2025~400K~$1.25~$10Original GPT-5 release
GPT-5 MiniAug 2025~400K~$0.25~$2Faster, cost-efficient variant of GPT-5; good for well-defined tasks at lower cost ([OpenAI Platform][1])
GPT-5 NanoAug 2025~400K~$0.05~$0.40Cheapest, fastest GPT-5 variant; great for summarization/classification workloads at very low cost ([LLM Stats][2])
GPT-4.1Apr 2024Longest-context OpenAI model
GPT-4.1 MiniApr 2025Lower-cost, faster variant; retains 1M context, good general-purpose option
GPT-4.1 NanoApr 2025Smallest, cheapest variant; fastest latency and economical usage
o3Apr 2025200K$2.00$8.00Highest-end o-series reasoning model; strong for complex multi-step reasoning (text + image input).
o4-miniApr 2025200K$1.10$4.40Fast, cost-efficient reasoning model; strong at coding + visual tasks (text + image input).
o3-miniJan 2025200K$1.10$4.40Small reasoning model optimized for STEM; text-only input (no vision).
GPT-4oMay 2024~128K~$5~$20Multimodal, low-latency GPT-4 successor

Note: in the Agent Builder, you'll see that we offer both a standard and a "Thinking" model option to choose from for some of the above models. The "Thinking" would support higher level of reasoning, but may also come at a higher cost and higher latency.

How to Choose the Right Model

AI models are continuously improving, and what is "the best" today may be surpassed in a few months (or even a few weeks). NinjaCat will continue evaluating and adding models that demonstrate better intelligence, efficiency, or performance.

For the latest information, check the following provider help documentation:

Claude Sonnet Claude Haiku OpenAI GPT-5.1 OpenAI ChatGPT 5 Prompting Guide OpenAI ChatGPT-4o OpenAI o3-mini OpenAI GPT 4.1 OpenAI o3 and o4-mini

Note: When switching between models, prompt adjustments may be required to maintain optimal Agent performance. We will provide further guidance on necessary prompt modifications as we continue testing and learning.