Function text_model_conformance 

pub async fn text_model_conformance(model: &dyn TextModel)

Asserts the TextModel trait contract against a text model whose transport is already scripted to complete text_model_conformance_prompt with TEXT_MODEL_CONFORMANCE_REPLY and the canonical counts in its vendor’s wire shape. The suite makes exactly one complete call — script that one request and no other.

Asserted, each panic naming the rule it caught:

1. text is the canonical reply, verbatim — no greeting, no chit-chat, no markdown fence around it;
2. model is non-empty — a completion names what answered, for the log line;
3. usage is reported on every completion: input_tokens and output_tokens equal the scripted counts;
4. cached_input_tokens is the scripted cache read, and never exceeds input_tokens — the cached subset of a total cannot be larger than the total;
5. the prompt carried no schema, so json is None.

// In the adapter's own test, after scripting its transport:
text_model_conformance(&model).await;

Panics

Panics with the failing rule named when the contract is violated, and when the scripted completion fails.