> For the complete documentation index, see [llms.txt](https://docs.airops.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.airops.com/actions/workflow-concepts/workflow-steps/ai-steps/llm/choosing-a-model.md).
# Model Selection Guide
## Choose a Model
The model you select affects output quality, speed, cost, and the features available in a [Prompt LLM step](/actions/workflow-concepts/workflow-steps/ai-steps/llm.md). Use the model picker as the source of truth for availability in your workspace.
### What to Consider
Compare these factors before selecting a model:
1. **Context window:** Check how much input the model can process. One token is roughly four characters in English.
2. **Task complexity:** Use stronger reasoning models for planning, analysis, and multi-step logic.
3. **Web access:** Confirm that the model supports web research when the task needs current information.
4. **Cost:** Compare the model's cost tier in the picker, especially for high-volume Workflows.
5. **Speed:** Balance response time against the reasoning depth the task requires.
## Common AirOps Models
The following models cover common use cases in new Workflows. A checkmark means the capability is available in the AirOps Prompt LLM step.
| Model | Provider | Description | Context Window | Vision | JSON Mode | Web Access |
| ---------------------- | ---------- | ----------------------------------------------------------- | -------------- | ------ | --------- | ---------- |
| GPT-5.6 Sol | OpenAI | Flagship GPT-5.6 model for complex reasoning and coding | 1M | ✓ | ✓ | ✓ |
| GPT-5.6 Terra | OpenAI | Balanced GPT-5.6 model for strong performance at lower cost | 1M | ✓ | ✓ | ✓ |
| GPT-5.6 Luna | OpenAI | Cost-efficient GPT-5.6 model for high-volume workloads | 1M | ✓ | ✓ | ✓ |
| GPT-5.5 | OpenAI | Previous flagship for complex reasoning tasks | 1M | ✓ | ✓ | ✓ |
| GPT-5.4 | OpenAI | Advanced model for professional work | 1M | ✓ | ✓ | ✓ |
| GPT-5.4 Mini | OpenAI | Faster GPT-5.4 model for well-defined tasks | 400K | ✓ | ✓ | ✓ |
| GPT-5.4 Nano | OpenAI | Cost-efficient GPT-5.4 model for lightweight tasks | 400K | ✓ | ✓ | ✓ |
| GPT-5.2 | OpenAI | Flagship with enhanced long-context reasoning | 400K | ✓ | ✓ | ✓ |
| GPT-5.1 | OpenAI | Model for coding and agentic tasks | 200K | ✓ | ✓ | ✓ |
| GPT-5 | OpenAI | Model for complex tasks | 200K | ✓ | ✓ | ✓ |
| O3 Pro | OpenAI | Advanced model for complex reasoning | 200K | ✓ | ✓ | - |
| O3 | OpenAI | Reasoning model with web research | 200K | ✓ | ✓ | ✓ |
| Claude Opus 5 | Anthropic | For complex agentic coding and enterprise work | 1M | ✓ | - | ✓ |
| Claude Fable 5 | Anthropic | Demanding reasoning and long-horizon agentic work | 1M | ✓ | - | ✓ |
| Claude Sonnet 5 | Anthropic | Hybrid reasoning for fast answers or deep thinking | 1M | ✓ | - | ✓ |
| Claude Opus 4.8 | Anthropic | Previous flagship for complex multi-step tasks | 1M | ✓ | - | ✓ |
| Claude Opus 4.7 | Anthropic | Complex reasoning, coding, and long-context work | 1M | ✓ | - | ✓ |
| Claude Opus 4.6 | Anthropic | Complex reasoning and coding | 200K | ✓ | - | ✓ |
| Claude Sonnet 4.6 | Anthropic | Current Sonnet option for complex tasks | 200K | ✓ | - | ✓ |
| Claude Haiku 4.5 | Anthropic | Fast model for lightweight tasks | 200K | ✓ | - | ✓ |
| Gemini 3.5 Flash | Google | Fast model with Google Search grounding | 1M | - | ✓ | ✓ |
| Gemini 3.1 Pro Preview | Google | Advanced reasoning with Google Search grounding | 1M | - | ✓ | ✓ |
| Gemini 3 Flash Preview | Google | Fast model for lightweight tasks | 1M | - | ✓ | ✓ |
| Gemini 3.1 Flash Lite | Google | Cost-efficient model for lightweight tasks | 1M | - | ✓ | ✓ |
| Perplexity Sonar | Perplexity | Balanced model for online web research | 128K | - | - | ✓ |
## OpenAI Models
### GPT-5 Series
GPT-5 models combine reasoning with general-purpose generation. GPT-5.6 appears in the model picker as Sol, Terra, and Luna. AirOps selects GPT-5.6 Sol by default for new Prompt LLM steps.
Reasoning controls vary by model:
* GPT-5 supports `minimal`, `low`, `medium`, and `high`.
* GPT-5.1, GPT-5.2, GPT-5.4, GPT-5.5, and GPT-5.6 support `none`, `low`, `medium`, and `high`.
### O3 Models
Use O3 for complex, multi-stage reasoning. O3 supports `low`, `medium`, and `high` reasoning levels. O3 Pro increases reasoning capability but does not support web research in the Prompt LLM step.
## Differences between Claude Models
### Claude Opus 5
Claude Opus 5 handles complex agentic coding and enterprise work. Turn on **Enable Thinking** in the Prompt LLM step when the task benefits from additional reasoning. Claude Opus 5 supports **Web Research**, but it does not support **Web Fetch**.
### Claude Fable 5
Claude Fable 5 supports demanding reasoning and long-horizon agentic work.
### Claude Sonnet 5
Claude Sonnet 5 balances fast responses with deeper reasoning and is starred in the LLM model picker.
### Claude Opus 4.8 and 4.7
Claude Opus 4.8 and 4.7 support complex, multi-step Workflows, long-form content, and research tasks. Both models support 1M-token context windows.
### Claude Sonnet 4.6 and Haiku 4.5
Use Claude Sonnet 4.6 for complex tasks that need a balance of reasoning and speed. Use Claude Haiku 4.5 for lighter workloads.
## Model Availability
AirOps hides deprecated models from the picker for new Workflows. If an existing Workflow uses a deprecated model, the selected model remains visible so you can review the change. AirOps may automatically update the selection to a supported model when the Workflow loads.
Review the selected model and test the Workflow after an automatic update. Model behavior, cost, and supported settings can change between versions.
{% hint style="warning" %}
* Claude Opus 4.1 is deprecated and scheduled for removal on August 5, 2026. Select Claude Opus 4.8 or another current model and test affected Workflows before the removal date.
* Gemini 2.5 Pro and Gemini 2.5 Flash are deprecated and scheduled for removal on October 16, 2026. Select a current model from the picker and test affected Workflows before the removal date.
{% endhint %}
## Web Search Capabilities
Several models support web research, allowing them to access current information during generation:
**OpenAI:** GPT-5, GPT-5.1, GPT-5.2, GPT-5.4, GPT-5.4 Mini, GPT-5.4 Nano, GPT-5.5, GPT-5.6 Sol, GPT-5.6 Terra, GPT-5.6 Luna, and O3 support web research when enabled in the Prompt LLM step.
**Anthropic:** Current Claude models support web research. Web Fetch availability depends on the selected model. Claude Opus 5 supports **Web Research**, but not **Web Fetch**.
**Google:** Current Gemini models support web research through Google Search grounding.
**Perplexity:** Sonar models include web access for online research.
## How much will it cost to run?
The cost to run a model depends on the number of input and output tokens.
### Token Approximation
**Input tokens:** to approximate the total input tokens, copy and paste your system, user, and assistant prompts into [the OpenAI tokenizer](https://platform.openai.com/tokenizer)
**Output tokens:** to approximate the total output tokens, copy and paste your output into [the OpenAI tokenizer](https://platform.openai.com/tokenizer)
### Cost Approximation
**OpenAI:** divide the input and output tokens by 1000; then multiply by their respective costs [based on OpenAI pricing](https://openai.com/pricing)\*
**Anthropic:** divide the input and output tokens by 1,000,000; then multiply by their respective costs [based on Anthropic pricing](https://www-cdn.anthropic.com/files/4zrzovbb/website/31021aea87c30ccaecbd2e966e49a03834bfd1d2.pdf)\*
{% hint style="info" %}
\*This is the cost if you [bring your own API Key](/your-workspace/settings/byo-key.md). If you choose to use AirOps hosted models, you will be [charged tasks according to your usage](https://airopshq.notion.site/AirOps-Task-Pricing-by-Hosted-Service-fd825db1300545cb8c3b5de8bc16529e).
{% endhint %}
---
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