implement-provider-adapter

name	implement-provider-adapter
description	Add or update a model provider/backend adapter with explicit capabilities, raw evidence, normalized requests/responses, errors, usage, and no hidden agency.

Implement provider adapter

Read first

• docs/protocol/PROVIDER_CONTRACT.md;
• docs/architecture/PROVIDER_ARCHITECTURE.md;
• docs/engineering/PROVIDER_ADAPTER_GUIDE.md;
• retention and redistribution gates.

Workflow

1. Confirm provider terms and artifact policy are compatible with intended tests.
2. Create capability matrix with native, emulated, unsupported, unknown.
3. Implement canonical request lowering without mutating semantic content silently.
4. Capture provider/model identifiers and request metadata.
5. Normalize response while preserving raw bytes/JSON under policy.
6. Map errors into timeout, throttling, transport, refusal, invalid request and unknown outcome.
7. Extract reported usage; keep missing fields unknown.
8. Disable SDK retries/fallbacks or surface each attempt explicitly.
9. Add golden fixtures for text, structured output, images, tools, refusal and failures.
10. Pass the common backend contract suite offline.

Forbidden

• model fallback;
• memory or agent loop;
• tool execution;
• unrecorded prompt rewrite;
• pricing network lookup;
• unsupported modality dropped silently;
• estimated tokens marked as provider-reported.

Handoff

Include capability table, exact SDK/version, terms note, fixture provenance, unsupported behaviors and any emulation that changes experimental interpretation.