ocai-anthropic

The Anthropic plugin distribution for ocai. Distribution name: ocai-anthropic; pip install ocai[anthropic] resolves to the same wheel. Requires Python 3.13+ and ocai>=0.1,<0.2.

It ships only ocai/anthropic/ into the shared ocai PEP 420 namespace, organized one subpackage per wire interface. Today that is one:

• ocai.anthropic.messages — the /v1/messages interface: typed wire structs, the codec, contract-censused conversion edges, the capability profile, and the chat component. Unary and streaming calls are implemented and certified against recorded fixtures.

What installing it does

Exactly one structural thing: the frozen ocai.anthropic.FRAGMENT (a CatalogFragment) becomes discoverable through the ocai.fragments entry-point group, so ocai.chat.model("anthropic/<model>", ...) can resolve the provider and the conversion graph gains Anthropic's nodes and edges. Importing ocai.anthropic is inert; there is no import-time registration. Applications that want an explicit catalog compose it themselves with Catalog.of(ocai.anthropic.FRAGMENT).

from ocai.anthropic import chat_model
from ocai.core import ApiKey

model = chat_model(
    "claude-sonnet-4-5",
    credentials=ApiKey.from_env("ANTHROPIC_API_KEY", header="x-api-key", scheme=""),
)
result = model.chat(...)   # needs ocai[http] and a real key

Anthropic authenticates with the x-api-key header, hence the explicit header=/scheme=; the required anthropic-version header is injected by the interface's declared traits. chat_model is sugar over ocai.chat.model("anthropic/<model>", ...) on a catalog built from this fragment, never a separate code path.

Boundaries

• No anthropic SDK: ocai owns the wire through ocai.wire. This plugin depends on ocai.core + ocai.convert + ocai.chat only, never on ocai.wire or httpx, so archived traffic can be re-converted by tooling with no ability to make network calls.
• msgspec is used only at the wire-decode boundary.
• Every conversion edge declares an EdgeContract and ships golden fixtures in the repository's spec/.

License

Source-available under FSL-1.1-ALv2 (converting to Apache-2.0 two years after each release). ocai is not open source.