Skip to main content

​
OpenAI

OpenAI provides developer APIs for GPT models. Fased exposes one OpenAI brand with two auth methods: OpenAI API key for Platform API access and OpenAI sign-in for ChatGPT OAuth access through the legacy internal openai-codex compatibility route.

​
Where to set it up

Use the same two OpenAI methods in every setup surface:
SurfaceWhat to do
Control UIOpen Agents, select an Agent, then use Agent > Models. Choose OpenAI, then Sign in or API key, and assign the Agent’s model roles there. Chat can override the model for the current session.
OnboardingChoose Set up model providers only if you want provider setup during onboarding, then choose OpenAI (OpenAI sign-in + API key) and pick OpenAI sign-in or OpenAI API key.
CLIUse fased onboard --auth-choice openai-codex for sign-in, fased onboard --auth-choice openai-api-key, or fased onboard --openai-api-key "$OPENAI_API_KEY" for API key setup.
The two auth methods use different internal routes:
  • Sign in stores OAuth credentials for openai-codex and exposes openai-codex/* model refs.
  • API key stores an API-key profile for openai and exposes openai/* model refs.
Do not mix the route prefix manually. Pick the method first, then choose a model from that method’s model list in Agent > Models or Chat.

​
Option A: OpenAI API key (OpenAI Platform)

Best for: direct API access and usage-based billing. Get your API key from the OpenAI dashboard.

​
API key control UI setup

  1. Open Agents and select the Agent.
  2. Open Agent > Models.
  3. Open OpenAI.
  4. Use API key and paste an OpenAI Platform key.
  5. Choose the Agent’s OpenAI model roles.
The credential is stored in the agent auth profile store as openai:default.

​
API key onboarding setup

fased onboard
# choose: Set up model providers -> OpenAI -> OpenAI API key

​
API key CLI setup

fased onboard --auth-choice openai-api-key
# or non-interactive
fased onboard --openai-api-key "$OPENAI_API_KEY"

​
API key config snippet

{
  env: { OPENAI_API_KEY: "sk-..." },
  agents: { defaults: { model: { primary: "openai/gpt-5.5" } } },
}

​
Option B: OpenAI sign-in (ChatGPT)

Best for: using ChatGPT OAuth access instead of an API key.

​
Sign-in control UI setup

  1. Open Agents and select the Agent.
  2. Open Agent > Models.
  3. Open OpenAI.
  4. Choose Sign in.
  5. Open or copy the sign-in URL shown in the modal.
  6. Finish OpenAI login in the browser.
  7. Return to Agent > Models after the modal reports success, then choose a model role for the Agent or use Chat to override a single session.
The credential is stored under the openai-codex compatibility route. This is why the model refs are openai-codex/... even though the user-facing provider brand is OpenAI.

​
Sign-in onboarding setup

fased onboard
# choose: Set up model providers -> OpenAI -> OpenAI sign-in

​
Sign-in CLI setup

# Run OpenAI sign-in in the wizard
fased onboard --auth-choice openai-codex

# Or run OAuth directly
fased models auth login --provider openai-codex

​
Sign-in config snippet

{
  agents: { defaults: { model: { primary: "openai-codex/gpt-5.5" } } },
}

​
Sign-in transport default

For openai-codex/* sign-in models, Fased uses its managed OpenAI sign-in transport. You can set agents.defaults.models.<provider/model>.params.transport when you need to force the streaming path:
  • Default is "auto" (WebSocket-first, then SSE fallback).
  • "sse": force SSE
  • "websocket": force WebSocket
  • "auto": try WebSocket, then fall back to SSE
{
  agents: {
    defaults: {
      model: { primary: "openai-codex/gpt-5.5" },
      models: {
        "openai-codex/gpt-5.5": {
          params: {
            transport: "auto",
          },
        },
      },
    },
  },
}

​
OpenAI Responses server-side compaction

For direct OpenAI Responses models (openai/* using api: "openai-responses" with baseUrl on api.openai.com), Fased now auto-enables OpenAI server-side compaction payload hints:
  • Forces store: true (unless model compat sets supportsStore: false)
  • Injects context_management: [{ type: "compaction", compact_threshold: ... }]
By default, compact_threshold is 70% of model contextWindow (or 80000 when unavailable).

​
Enable server-side compaction explicitly

Use this when you want to force context_management injection on compatible Responses models (for example Azure OpenAI Responses): 
{
  agents: {
    defaults: {
      models: {
        "azure-openai-responses/your-model-id": {
          params: {
            responsesServerCompaction: true,
          },
        },
      },
    },
  },
}

​
Enable with a custom threshold

{
  agents: {
    defaults: {
      models: {
        "openai/gpt-5.5": {
          params: {
            responsesServerCompaction: true,
            responsesCompactThreshold: 120000,
          },
        },
      },
    },
  },
}

​
Disable server-side compaction

{
  agents: {
    defaults: {
      models: {
        "openai/gpt-5.5": {
          params: {
            responsesServerCompaction: false,
          },
        },
      },
    },
  },
}
responsesServerCompaction only controls context_management injection. Direct OpenAI Responses models still force store: true unless compat sets supportsStore: false.

​
Notes

  • Model refs always use provider/model (see /concepts/models).
  • Auth details + reuse rules are in /concepts/oauth.
  • Agent > Models owns OpenAI credentials and that Agent’s model roles. Chat can choose a session-level model from the authenticated provider catalog.