litellm compat patches

Reyn works around real litellm defects in two places, split by which litellm install the defect lives in: reyn's own in-process litellm (this page's own "lib" section), and the owner's junk/litellm proxy (a separate installation, a separate version — this page's own "proxy" section).

Lib side — retired (#5620)

src/reyn/llm/_litellm_compat_patches.py (#5603) used to carry 2 monkeypatches applied once inside ensure_litellm_ready()'s own startup chokepoint:

• A (apply_stream_chunk_recovery) — targeted ResponsesToCompletionBridgeHandler._collect_response_from_stream_async, litellm's Responses→chat-completions bridge.
• B (apply_overflow_diagnosis) — targeted ChatGPTResponsesAPIConfig, a Responses-API config class reyn's own production code never uses (reyn uses OpenAIResponsesAPIConfig, #5568).

Both are removed (#5620), with 0 reachability on reyn's real production call path, verified directly rather than assumed:

• B: reyn never constructs a ChatGPTResponsesAPIConfig — it is a different Responses-API config class than the one reyn's own resolved models route through (#5568's own record).
• A: a real httpx.MockTransport-driven call through litellm.acompletion() (5 caller-shape combinations — streaming and non-streaming, a plain reasoning model and a Responses-only model), against the installed litellm 1.96.2, never once reached the private method A patched — the caller-level stream flag and the bridge's internal HTTP-level stream flag are always identical under this litellm version, so the "caller asked for stream=False but the bridge received a streaming object anyway" state A existed to recover from cannot occur. See PR history for the full trace.

reyn's own classification-side response to the underlying incident this patch module was built around lives in #5614 (classify_llm_failure's own code == 200 branch, src/reyn/services/compaction/engine.py) — that fix is unaffected by this retirement; it corrects reyn's own failure classification, not litellm's bridge internals.

No lib-side reyn doctor section or audit-event remains — there is nothing left to measure.

Proxy side (#5620)

scripts/litellm_proxy_patch/ — a standalone patch (no reyn import) for the owner's own junk/litellm proxy, a SEPARATE litellm installation (its own venv, python3.13, litellm 1.95.0 + the proxy extra) from reyn's own in-process litellm. Owner ruling (2026-08-30): "proxy はランタイムだけで良い" — the proxy venv never gets a reyn install.

The defect (D): a proxy client requesting stream: false on a /v1/responses call routed to the chatgpt provider still gets raw SSE pass-through (and, on a mid-stream upstream error, a trailing data: {"error": {...}} frame rather than a real HTTP 4xx/5xx) instead of the plain JSON a stream: false caller expects. Full traced chain: scripts/litellm_proxy_patch/litellm_proxy_patch.py's own module docstring. Reached only when {caller stream=false, provider=chatgpt, litellm hands back a raw streaming iterator anyway} — every other shape falls through unchanged.

Install / verify / uninstall: scripts/litellm_proxy_patch/README.md. Status file: ~/.reyn/litellm-proxy-patch-status.json (path/schema: src/reyn/llm/litellm_proxy_patch_status.py) — written by the proxy process itself; reyn doctor reads the same file (a separate process this reyn process never imports or connects to).

Regression detection: tests/scaffold/test_5620_litellm_proxy_ defects.py reproduces the 3 upstream defects D's own chain depends on, pinned to litellm 1.95.0 (importlib.metadata.version("litellm")) — a different installed version skips with an explicit qualifier (not a bare skip), and CI carries a dedicated, path-conditional leg that installs litellm[proxy]==1.95.0 in its own venv specifically to run this file un-skipped. RED there (the defect no longer reproduces) is GOOD NEWS — see that test file's own module docstring for the removal instructions when it fires. tests/llm/test_5620_litellm_proxy_patch_d.py exercises D's own patched behavior (real/broken SSE fixtures) and the path/schema parity gate between this page's 2 copies of the status-file literal.

When to remove: scripts/litellm_proxy_patch/README.md's own "When to remove this entirely" section.