Configuration for the OpenAI model provider.
A provider block with kind = "openai" configures the OpenAI cloud provider. It also works with any
OpenAI-compatible endpoint, such as Azure OpenAI or a local proxy, by setting config.base_url.
| Field | Type | Required | runtime() | Default | Description |
|---|---|---|---|---|---|
kind | openai | yes | no | … | Provider kind. |
models | array<string | ModelEntry> | no | no | unset | Models permitted for this provider, with optional model-specific inference settings. |
config | ProviderConfig | no | unset | API credentials and endpoint settings for this provider. | |
params | InferenceParams | no | unset | Default inference settings for requests to this provider. |
When config.api_key is unset, the key is read from the OPENAI_API_KEY environment variable. The
agent fails to start when neither is set.
| Field | Type | Required | runtime() | Default | Description |
|---|---|---|---|---|---|
name | string | yes | no | … | Model identifier. |
params | InferenceParams | no | unset | Model-specific inference parameter overrides. |
| Field | Type | Required | runtime() | Default | Description |
|---|---|---|---|---|---|
api_key | string | no | yes | unset | OpenAI API key. Wrap in secret(runtime(...)) to keep it out of build artifacts. |
base_url | string | no | yes | unset | API base URL. Override to point at a compatible endpoint such as Azure OpenAI or a local proxy. |
headers | map<string, HeaderValue> | no | yes | {} | HTTP headers sent with every model request, keyed by header name. Header names are case insensitive. |
A header value is one of:
| Form | Header value |
|---|---|
| a string | The string, unchanged. |
expression("source") | The result of the CEL expression source, evaluated for each model request. |
config {
headers = {
"X-Team" = "platform"
"X-Tenant-Id" = expression("ctx.tenant_id")
}
}For the values an expression can read and how evaluation fails, see Send custom headers.
The params block sets inference parameter defaults for all models under this provider. All fields
are optional and support runtime().
| Field | Type | Required | runtime() | Default | Description |
|---|---|---|---|---|---|
max_tokens | integer | no | yes | unset | Maximum number of tokens to generate. |
temperature | number | no | yes | unset | Controls randomness when selecting the next token; higher values produce more varied output. |
top_p | number | no | yes | unset | Selects tokens from the smallest group whose combined probability reaches this value. |
top_k | integer | no | yes | unset | Limits the next-token choices to the K most likely tokens. |
stop_sequences | array<string> | no | yes | unset | Sequences that stop generation. |
frequency_penalty | number | no | yes | unset | Reduces repetition by penalizing tokens according to how often they have appeared. |
presence_penalty | number | no | yes | unset | Penalizes tokens that have already appeared to reduce repetition. |
seed | integer | no | yes | unset | Seed for deterministic sampling. |
provider_params | object | no | yes | unset | Additional provider-specific inference options sent directly to the API. |
provider "openai" {
kind = "openai"
models = [
"gpt-4o-mini",
{
name = "gpt-4o"
params {
max_tokens = 8192
temperature = 0.3
}
}
]
config {
api_key = secret(runtime("OPENAI_API_KEY"))
base_url = runtime("OPENAI_BASE_URL", "https://api.openai.com/v1")
}
params {
max_tokens = 2048
temperature = 0.5
frequency_penalty = 0.1
}
}In this example, requests to gpt-4o-mini use the provider-level defaults. Requests to gpt-4o
use its own model-level params for max_tokens and temperature, while still inheriting
frequency_penalty from the provider-level defaults.
Always wrap API keys in secret(runtime(...)). This prevents the key from appearing in build
artifacts and the output of agentc inspect.
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