Skip to main content
Guild supports GPT and o-series models from OpenAI. This page lists the models Guild recognizes, the inference providers that serve them, and how to call them from an agent.

​
Inference providers

You can reach these models through the OpenAI API itself or through a third-party provider. Write the canonical model name, such as gpt-4o, everywhere in Guild. Guild maps it to each provider’s own model ID.

​
Models

Guild prices and recognizes these OpenAI model IDs. A policy or preference can also name any other model your credential can reach.

​
Set up OpenAI

On a managed account, agents can use OpenAI models without a credential, as long as Guild holds a managed key for OpenAI. To use your own OpenAI account instead, add a credential. Adding your first credential switches the whole account to bring your own key (BYOK).
1

Open Models & providers

Click Access & setup in the left nav, then Models & providers. In an organization, only admins can open it.
2

Add a credential

Click Add API key and choose an inference provider from the table above.
3

Enter the provider's secret

Give the credential a Name and paste your provider’s API key. AWS Bedrock asks for an IAM role and region instead.
4

Choose OpenAI

Under Models, check OpenAI. Keep gpt-4o as its default model or enter another from the list above. Then click Add Key.
To control which workspaces and agents can use OpenAI models, add a model policy for the credential. For example, --models "gpt-5*" limits a policy to matching models:

​
Use it from an agent

Agent code never names a credential. Guild resolves the call against the workspace owner’s settings. To ask for OpenAI explicitly, put it in llmPreferences:
The first entry asks for gpt-5. The second falls back to the default model of the matching policy. Preferences are strict: if no credential or policy allows any of them, the call fails rather than using another publisher. See LLM preferences.

​
Notes

  • OpenAI streaming responses always include token usage, so Guild can attribute spend to the session.
  • Guild removes reasoning parameters a model doesn’t accept, so the same request works across GPT and o-series models.
  • The Codex runtime driver calls the OpenAI Responses API through the runtime, so it needs an OpenAI credential or managed OpenAI access.
  • Models & providers for credentials, model policies, and the daily token limit
  • LLMs for task.llm and the unified LLM proxy
  • Usage for spend by model