Host interface

The host interface is the provider-neutral boundary between Condukt's portable session and application-owned capabilities.

Completion request#

A completion request contains:

• messages: the complete conversation history required for the next model response.
• tools: the definitions registered by the current host.

Each tool definition has a unique name, a human-readable description, and a JSON Schema object describing its arguments.

Starting a turn#

submit(prompt) records a user message and returns the first completion request. A session rejects another submission while the current turn is waiting for inference or tool results.

Receiving inference#

receive_completion(message) accepts an assistant message and produces one of two results:

• complete contains the final assistant message.
• run_tools contains the assistant message and the requested tool calls.

The host must reject or translate provider responses that do not have the assistant role before passing them to the session.

Returning tool outputs#

receive_tool_outputs(outputs) requires exactly one output for every requested tool call. Each output contains:

The identifiers and order must match the outstanding calls. Condukt records the tool results and returns the next completion request.

Host responsibilities#

The host owns:

• provider credentials and model selection;
• network transport, retries, and request limits;
• tool argument validation and execution;
• cancellation and application lifecycle;
• presentation of messages and tool activity.

The portable session owns conversation history, state transitions, and validation that completion and tool results arrive in the expected order.