Model Setup Guide
GPT-6 Sol and Luna on Hermes Agent and OpenClaw
OpenAI released Sol and Luna on September 22, 2026. Here are the verified model IDs, API prices, and setup paths for both agent frameworks.
What changed
OpenAI announced gpt-6-sol and gpt-6-luna on September 22. Both accept text and image input and return text. OpenAI describes Sol as the choice for complex coding and agent workflows, and Luna as its efficient choice for focused work at scale. They join GPT-6 Astra, which remains the highest capability tier.
Prices and limits
| Standard API, per 1M tokens | GPT-6 Sol | GPT-6 Luna |
|---|---|---|
| Model ID | gpt-6-sol | gpt-6-luna |
| Input | $2.00 | $0.10 |
| Cached input | $0.20 | $0.01 |
| Cache writes | $2.50 | $0.125 |
| Output | $10.00 | $0.50 |
| Context window | 1,050,000 tokens | 1,050,000 tokens |
| Maximum output | 128,000 tokens | 128,000 tokens |
| Knowledge cutoff | April 20, 2026 | May 18, 2026 |
These are Sol and Luna Standard API rates for prompts up to 272,000 input tokens. Above that threshold, OpenAI applies 2× input and cache rates and 1.5× output rates to the whole request. Batch and Flex are half of Standard rates. A 1.05M-token window is a ceiling, not a reason to send every session that much context.
Both models support none, low, medium, high, xhigh, and max reasoning effort. OpenAI recommends the Responses API for tool use. In Chat Completions, Sol and Luna support function calling only when reasoning effort is none; use Responses when an agent needs reasoning and tools together.
Managed Hermes Agent setup
- Add your OpenAI API key under API Keys.
- Open your Hermes Agent model picker. If Sol or Luna is not listed, use the custom model fields: platform
openaiand model IDgpt-6-solorgpt-6-luna. - Apply the change and start a new session. Your OpenAI API account must have access to the chosen model.
The managed Hermes custom model path uses the same model value for Sol and Luna. OpenClaw Launch's curated model picker may take time to list new releases; check what your specific bot offers before changing it.
Managed OpenClaw uses the same model picker and your OpenAI API key, but its runtime must also recognize the model. Choose Sol or Luna there only when it appears as an available OpenAI model for that bot; a custom ID entered before catalog support can fail on the first turn. The self-hosted registration steps below explain that difference.
Self-hosted Hermes Agent
Put the key in ~/.hermes/.env, then set provider and model separately in ~/.hermes/config.yaml. The example selects Sol; replace the bare ID with gpt-6-luna to use Luna.
# ~/.hermes/.env
OPENAI_API_KEY=sk-...
# ~/.hermes/config.yaml
model:
provider: "openai-api"
default: "gpt-6-sol"Run hermes model if you prefer the provider wizard. Start a new session after changing the default. Hermes does not use the OpenClaw openai/ prefix in model.default. See the upstream configuration example.
Self-hosted OpenClaw
OpenClaw uses provider-prefixed references. Set up an OpenAI API-key auth profile, inspect your installed catalog, and then select a model that resolves:
openclaw onboard --auth-choice openai-api-key
openclaw models auth list --provider openai
openclaw models list --provider openai
openclaw models set openai/gpt-6-sol
# or: openclaw models set openai/gpt-6-lunaNew model IDs can arrive before an OpenClaw release includes them in its local catalog. If the agent reports Unknown model, add the missing entries to your existing models.providers.openai.models array. The following openclaw.json excerpt selects Sol; change primary to openai/gpt-6-luna for Luna.
{
"models": {
"providers": {
"openai": {
"models": [
{ "id": "gpt-6-sol", "name": "GPT-6 Sol" },
{ "id": "gpt-6-luna", "name": "GPT-6 Luna" }
]
}
}
},
"agents": {
"defaults": {
"model": { "primary": "openai/gpt-6-sol" },
"models": {
"openai/gpt-6-sol": { "agentRuntime": { "id": "openclaw" } },
"openai/gpt-6-luna": { "agentRuntime": { "id": "openclaw" } }
}
}
}
}Merge these entries with any provider models and other settings you already have; do not replace the full config with the excerpt. The explicit agentRuntime.id keeps these examples on OpenClaw's embedded runtime. If you also have a Codex subscription profile, verify that the API-key profile is selected first in auth.order.openai for this agent. A successful config write does not prove API access. Check the upstream OpenAI setup and routing guide and model CLI guide for your installed version.
Keep API key billing separate from ChatGPT or Codex subscription access. The availability of Sol or Luna in a subscription account does not establish that an OpenClaw runtime can run that model through subscription authentication.
Which model should you start with?
Choose Sol for a coding or research agent that has to plan and use tools across several steps. Try Luna for classification, extraction, short summaries, and frequent bounded automations. Test the same real tasks on both models and compare quality, latency, and total token use; per-token price alone does not measure cost per successful task.
For complex work where failures are costly, compare both with GPT-6 Astra. OpenAI's GPT-6 model guidance explains the family's tool and reasoning settings.
GPT-6 Sol and Luna FAQ
What are the GPT-6 Sol and Luna model IDs?
Use gpt-6-sol or gpt-6-luna with the OpenAI API. Hermes Agent keeps those bare IDs in model.default; OpenClaw uses openai/gpt-6-sol or openai/gpt-6-luna.
Do GPT-6 Sol and Luna work on Hermes Agent?
Yes, through Hermes Agent's direct OpenAI API provider. Add your OPENAI_API_KEY, set model.provider to openai-api, and set model.default to either new model ID. Start a new session after changing the default.
Do GPT-6 Sol and Luna work on OpenClaw?
OpenClaw uses an openai/ model reference. Check openclaw models list for your installed build. If a new model is absent from its local catalog, register it under the OpenAI provider before selecting it; a saved model name alone does not prove an agent turn can resolve or call it.
Which should I choose for an agent?
Start with Sol for coding and multi-step work. Try Luna for frequent, focused tasks where lower cost matters. Use the same representative tasks to compare results before changing an existing agent's default. For the hardest work, see our GPT-6 Astra guide.