Module provider 

Choosing a provider and finding its credential.

Which model answers is configuration, not a basis opinion — but finding the credential is glue every embedder would otherwise write, so basis does it once, by the environment-variable names the ecosystem already uses.

Nothing here repeats what it read

The value this module goes looking for is a credential, so ProviderChoice’s Debug redacts it. That is not hypothetical tidiness: a resolution test that failed with the wrong variables exported printed a live key into a terminal, because expect formats the Ok it did not want. The same rule as WorkspaceBuilder’s own Debug.

The environment is a parameter

Resolution consults the environment in three places — the base URL, the compatible-endpoint key, and auto-detection — which is enough to make every test of it a test of the shell that started it. So the lookup is passed in, exactly as crate::mcp passes one to ${VAR} expansion, and the rules below can be pinned without mutating the process’s own environment.

Structs

ProviderChoice

A provider together with the key it will authenticate with.

Enums

ProviderError

Functions

key_var

The environment variable holding provider’s key, if it has one.

normalize_base_url

Trims a base URL to what mentra’s Responses transport expects.

parse

Parses a provider name as written on a command line or in config.

resolve

Resolves how basis will reach a model, with the credential read from the environment.

resolve_with

Resolves how basis will reach a model, with the credential supplied rather than looked up.