fix(api): tell the caller why a remote upstream refused, without naming it by krisztian-gajdar · Pull Request #744 · superlinked/sie

krisztian-gajdar · 2026-10-15T13:29:21Z

Summary

A self-hosted sie-server whose generation profile is served by an OpenAI-compatible upstream answered every failed request with 502 upstream_error: upstream generation request failed (single-node chat) or 500 inference_error: internal error during generation (native generation, completions, responses and a cluster). An upstream that answered 402 because its account had no credits looked the same to the caller as a rejected key or an unreachable host. Since #738 the server log names the cause, but the caller (for example a coding agent that shows only the error message) still could not see it.

The caller's error now names the class of the failure in a reason field, from a closed set. A failure that a retry would not fix carries that reason's fixed text as its message. The HTTP status and code do not change.

`reason`	Cause	Message of a final failure
`upstream_credential_unavailable`	the server has no credential to send (its environment variable is not set)	the server has no usable credential for its upstream
`upstream_credential_rejected`	the upstream answered `401`, or `403` without a known error code	the upstream rejected the server's credential
`upstream_payment_required`	the upstream answered `402`	the upstream account cannot pay for the request
`upstream_model_not_found`	the upstream answered `404`	the upstream has no route for the configured model
`upstream_refused`	another `4xx`, including a `403` whose code names the account's or service's state (`ACCOUNT_SUSPENDED`, `ACCOUNT_PENDING_REVIEW`, `THIRD_PARTY_*`)	the upstream refused the request
`upstream_unavailable`	unreachable, timed out (a transport timeout, a `408`, or a remote profile's own `first_chunk_timeout_s`/`overall_timeout_s` on a single node), a started stream closed, a `5xx`, an open circuit breaker, or an upstream that reported a failure without naming its class	the upstream could not be reached, timed out or failed
`upstream_busy`	`429`, a busy code, or the server's own rate or concurrency cap for the upstream	the upstream is busy
`upstream_not_ready`	the upstream reports the model is not ready	the model is not ready on the upstream
`upstream_invalid_response`	an answer the server does not accept: malformed, cut short, too large, compressed, a redirect, or a chat answer that breaks the request's tools or token limits	the upstream answered with something the server cannot accept

The reason names the cause. The status says whether a retry may help. A retryable failure stays a 503 with Retry-After and its existing message. A 429 with the final code COLD_START_RATE_LIMITED is a final failure whose reason is upstream_busy.

Example, single-node chat, upstream answered 402:

before: 502 {"error":{"message":"upstream generation request failed","type":"upstream_error","param":null,"code":"upstream_error"}}
after:  502 {"error":{"message":"the upstream account cannot pay for the request","type":"upstream_error","param":null,"code":"upstream_error","reason":"upstream_payment_required"}}

An upstream's refusal of the caller's own input (400/422, #737) stays 400 invalid_request with no reason.

How each failure is classed

HTTP status. By status and known error code, as in the table.
An error sent in place of an answer. Some upstreams answer 200 and then send an error object as the body or as a stream event, for example {"error":{"code":402,...}}. This is a final failure, classed by the HTTP status its numeric code names, and otherwise as upstream_unavailable. Before this PR it was always upstream_invalid_response.
An SIE upstream. An upstream that is itself an SIE server names the class of its own upstream's failure in reason, in its error body, its stream error event or its terminal event. The server keeps that class. When the class is final (not upstream_unavailable, upstream_busy or upstream_not_ready), the failure is final here too. Before this PR, an SIE upstream's 500 was always a retryable 503.
An SIE upstream's terminal error event (a 200 stream that ends with finish_reason: error):
- inference_error carries the class the event names, else upstream_unavailable.
- RESOURCE_EXHAUSTED and MODEL_LOADING carry upstream_busy and upstream_not_ready, before and after output.
- Any other code describes the request or the model's output, keeps its code and message, and carries no reason.
- Native generation, completions and template-rendered chat now give one event the same class. Rendered chat used to call it upstream_invalid_response.

Where the reason appears

Single node: chat (buffered and streamed, direct and rendered through the model's template), native generation (detail.reason, buffered and streamed), completions and responses, including the error event of a stream that already started. A remote profile's governed timeout keeps its 504 and code (first_chunk_timeout, overall_timeout, generation_timeout) and adds reason: upstream_unavailable. So does rendered chat that times out after output. A local profile's timeout carries no reason.
Queued worker: the terminal chunk's error.reason, for chat and native prompts, through both adapters. This covers a failed call, an in-band error and an SIE upstream's terminal event.
Gateway:
- It admits only the known names, and only on inference_error, RESOURCE_EXHAUSTED and MODEL_LOADING.
- It adds reason to the buffered OpenAI error and to every stream's error event (native, chat and completions).
- An inference_error of that class answers with the reason's fixed text instead of internal error during generation.
- An unknown reason is dropped, and the worker's own message for an inference_error still never reaches the caller.
Not carried:
- The gateway's own deadline (first_chunk_timeout/overall_timeout from the gateway) carries no reason, because that deadline also covers the queue and the worker and does not show which hop was slow.
- A request that falls back to a remote profile answers a failed remote attempt with the original local refusal, unchanged as REMOTE_BACKENDS.md already specifies. It names the attempt's failure only in X-SIE-Fallback-Error, so it carries no reason.
Contract files:
- packages/wire-fixtures/upstream_failure_reasons.json pins the names, their messages and the terminal error object a worker publishes for a 402. The worker test produces that exact object from a real 402, and the gateway decodes the same object.
- OpenAPI: the server documents reason on GenerateChunkErrorModel, on the native error detail (/v1/generate 500/503/504) and on the OpenAI error body of chat, completions and responses. The gateway documents GenerateChunkError.reason and OpenAIErrorBody.reason with an UpstreamFailureReason enum.
- The Python and TypeScript SDKs parse code, message, param and retry_after_s from these errors and do not parse reason, so they are unchanged. Their errors carry the new message. The reason itself is read from the raw body or through an OpenAI client.

What the caller does not see

The reason and message never contain the upstream's name, URL, model id, response body or account identifiers. The operator's WARNING line keeps that detail. X-SIE-Upstream still names the upstream on a remote response, as REMOTE_BACKENDS.md already documents.

Logging. Native generation, completions and template-rendered chat log these failures once in the adapter as remote generation failed: <reason>: a failed upstream call, an error sent in place of an answer, and an SIE upstream's terminal error event. Examples are upstream answered 402, upstream sent error 402 instead of a completion and upstream ended generation with inference_error upstream_payment_required. Rendered chat also logs an answer it refuses as remote chat for <model> failed: <reason>.

Behaviour changes beyond the caller's body

A remote adapter's generate() raises GenerationUpstreamError (a GenerationError) instead of RemoteUpstreamError for a final upstream failure. Nothing in this repository depends on the old type. The circuit breaker is unaffected, because the conversion happens outside the limiter block.
A queued native prompt whose upstream fails logs two WARNING lines: the adapter's remote generation failed and the processor's existing Generate iterator raised traceback for any adapter-raised generation error.
An SIE upstream's 5xx that names a final class is now final instead of a retryable 503.
THIRD_PARTY_SERVING_DISABLED, THIRD_PARTY_RUNTIME_UNLISTED and THIRD_PARTY_REGION_UNAVAILABLE are known upstream codes now. They are 403 codes, so they only change the class from upstream_credential_rejected to upstream_refused.

Deployment note

A deployment that serves other callers through its own upstream account exposes the reason class to those callers. A caller can learn that the operator's upstream account cannot pay, that its credential was rejected, or that the server has no credential configured. It never learns which upstream, account or key. No override exists today. Neither the server nor the gateway has a setting that replaces this text or drops the field, and the gateway's ModelAccessPolicy has no hook for error text. The gateway already replaces every worker inference_error message with fixed text and admits only the known reasons, so it is where such a switch would go if a deployment prefers generic wording. This PR does not add one. The gateway trusts a known reason from any worker on those three codes. A misbehaving local worker could therefore label a local failure with an upstream class, but only with the fixed text.

Validation

mise run lint, mise run typecheck: pass. mise run openapi regenerated the server spec.
Server, scripted upstream on the real routes, both the SIE and the OpenAI-compatible adapters:
- Every final failure (401, 402, 403, 403 ACCOUNT_SUSPENDED, 404, 408, 409, 429 COLD_START_RATE_LIMITED, an SIE upstream's 500 naming upstream_payment_required, 501, a malformed answer) and a connection failure. Each runs on native, chat, completions (buffered and streamed), responses, and chat rendered through the model's template (buffered and streamed). Each asserts the status, code, reason and message, that the credential was sent once, and that no upstream name, URL, path, model id, account id, response text or credential is in the body.
- An error the upstream reports in its answer, with and without a class: an in-band error object (OpenAI-compatible), an SIE upstream's terminal event or stream error event. It covers every surface and also rendered chat with tools, which goes through the tool-call parser. It asserts the caller body and the adapter's single log line.
- After output: a disconnect, a malformed event, a reported error with and without a class, and a rendered-chat timeout each end native, chat, completions and rendered-chat streams with the right reason and message. A retryable SIE terminal event after output carries upstream_busy or upstream_not_ready.
- Before output: a retryable SIE terminal event answers 503 with its Retry-After and reason on every route.
- A remote profile's timeout answers 504 with upstream_unavailable on native, completions, responses and rendered chat. A local profile's timeout carries no reason.
- Queued worker: the same failures, an in-band error and an SIE terminal event, on chat and on native prompts through both adapters.
tests/api, tests/processors, tests/adapters of sie_server: 7,481 passed, 76 skipped.
Gateway: the handler test drives native, chat, completions and responses (buffered and streamed) with worker terminals of inference_error, RESOURCE_EXHAUSTED and MODEL_LOADING that carry a reason. mise run gateway-test (with NATS, both feature sets: 1,742 and 1,753 passed), gateway-clippy and gateway-fmt -- --check: pass.
tools/ci/check_public_tree.py, tools/check_ipc_types_parity.py, tools/check_response_chunk_protocol.py: pass.
OpenCode example: CI=1 uv run --frozen pytest -q: 60 passed.

Mutations, each caught by at least one of the tests above (30 this round, 18 in the first):

Mutation	Caught by
`402` classified as `upstream_refused`; final `5xx` as `upstream_refused`; missing credential without its reason	server route tests
a `403` with a known code, a `408`, or a final `429` keeps the old class	server route tests
an SIE upstream's error-body `reason` ignored, or its final class left retryable	server route tests
an in-band error ignores its status, ignores its `reason`, or defaults to `upstream_invalid_response`; either parser keeps the generic in-band error	server reported-error tests
an SIE terminal event drops its reason, ignores the reason it names, or is not logged; a retryable terminal after output keeps no reason	server reported-error and terminal-event tests
native stream or buffered, completions stream, pre-output or buffered, and `collect_generation` drop a terminal chunk's reason	server route tests
rendered chat ignores a terminal chunk's reason; the tool-call parser drops it	server reported-error tests
a remote timeout without its reason on native, completions, rendered chat, or chat after output; a local timeout with one	server timeout tests
the worker drops a terminal chunk's reason, or does not convert a raised upstream error	worker tests
gateway SSE or buffered error drops `reason`; driver drops it; admits an unknown reason; ignores it on `RESOURCE_EXHAUSTED`/`MODEL_LOADING`; message ignores it	gateway handler, SSE and contract tests

Summary by CodeRabbit

New Features
- Error responses now include a structured reason for recognized remote generation failures across supported APIs and streaming responses, including credential, payment, model availability, and invalid-response issues.
- Messages use standardized, safe wording that omits upstream identifiers and sensitive response details.
- API documentation now describes the error response formats and available failure reasons.
Bug Fixes
- Failure reasons and safe messages are preserved when errors occur after streaming output has begun.

… error A remote generation failure reached the caller as a generic 'upstream generation request failed' (single-node chat) or 'internal error during generation' (native generation, completions, responses and the queued worker), so a caller could not tell a rejected credential from an account that cannot pay or an unreachable upstream. The caller's error now carries a closed-set 'reason' next to 'code' and 'message', and a final failure's message is that reason's fixed text. The HTTP status and code are unchanged, and nothing the upstream sent, nor its name, URL or model id, reaches the caller. The queued worker writes the same reason into its terminal chunk. The reason set and its text are pinned in a wire fixture.

A worker's terminal chunk can name the class of a remote upstream's failure. The gateway admits only the known reasons, adds 'reason' to the buffered OpenAI error and to every stream's error event, and answers an inference_error of that class with the reason's fixed text instead of the generic message. An unknown reason is dropped.

coderabbitai · 2026-10-15T13:29:51Z

📝 Walkthrough

The server and gateway add nine upstream failure reason values. Remote adapters classify failures and carry reasons through buffered responses and streaming errors. The gateway validates worker reasons and uses fixed public messages. OpenAPI schemas, documentation, fixtures, and tests cover the added reason fields and mappings.

Changes: Upstream failure reason propagation

Layer / File(s)	Summary
Classify remote upstream failures `packages/sie_server/src/sie_server/adapters/errors.py`, `packages/sie_server/src/sie_server/adapters/_generation_base.py`, `packages/sie_server/src/sie_server/adapters/remote/`, `packages/sie_server/src/sie_server/processors/remote_chat.py`, `packages/sie_server/tests/adapters/`	The server defines nine upstream failure categories and fixed public messages. Remote adapters map status, transport, and response failures to those categories and preserve them in generation errors.
Expose reasons in generation and chat errors `packages/sie_server/src/sie_server/api/`, `packages/sie_server/src/sie_server/processors/`, `packages/sie_server/src/sie_server/types/openapi.py`, `packages/sie_server/openapi.json`, `packages/sie_server/REMOTE_BACKENDS.md`, `packages/sie_server/tests/`, `packages/wire-fixtures/`	Generation, completions, and chat responses include available reasons in buffered errors and stream events. Tests cover reason mappings, fixed messages, response statuses, and omission of private details. OpenAPI schemas, documentation, and a shared fixture describe the reason values.
Validate and forward reasons at the gateway `packages/sie_gateway/src/queue/`, `packages/sie_gateway/src/handlers/`, `packages/sie_gateway/src/openapi.rs`, `packages/sie_gateway/openapi.json`	The gateway recognizes the nine reason values, uses fixed messages for classified errors, and includes available reasons in OpenAI and SSE error payloads. Tests cover serialization, fallback behavior, and message sanitization.

Sequence Diagram(s)

sequenceDiagram
  participant RemoteUpstream
  participant ServerAdapter
  participant GenerationAPI
  participant Gateway
  RemoteUpstream->>ServerAdapter: Return failure details
  ServerAdapter->>GenerationAPI: Classify failure and preserve reason
  GenerationAPI->>Gateway: Send error with optional reason
  Gateway->>Gateway: Validate reason and select safe message

Suggested reviewers: svonava

Priority: ➖ Normal

Merge Risk: 🔵 Low · up to 7bb55

An unusual third-party error response can prevent a retry and report the wrong failure class. Restricting trust in upstream-supplied reasons is advisable before merging.

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🟡 Minor · Pass the upstream reason for retryable SIE terminal events. · sie.py:767-770

packages/sie_server/src/sie_server/adapters/remote/sie.py:767-770
🗄️ Data Integrity & Integration | 🟡 Minor | ⚡ Quick win

Pass the upstream reason for retryable SIE terminal events.

When a streamed SIE terminal event arrives before output, _terminal_chunk raises GenerationDrainingError or GenerationCapacityError without upstream_reason. Native and queued error responses then omit upstream_not_ready or upstream_busy.

Suggested fix

-            raise GenerationDrainingError("the upstream is not ready, please retry", retry_after_s=event.retry_after_s)
+            raise GenerationDrainingError(
+                "the upstream is not ready, please retry",
+                retry_after_s=event.retry_after_s,
+                upstream_reason="upstream_not_ready",
+            )
...
-            raise GenerationCapacityError("the upstream is busy, please retry", retry_after_s=event.retry_after_s)
+            raise GenerationCapacityError(
+                "the upstream is busy, please retry",
+                retry_after_s=event.retry_after_s,
+                upstream_reason="upstream_busy",
+            )

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Review comment at @packages/sie_server/src/sie_server/adapters/remote/sie.py
around lines 767 - 770:
Update the _terminal_chunk handling for MODEL_LOADING and RESOURCE_EXHAUSTED
events to pass upstream_reason when raising GenerationDrainingError and
GenerationCapacityError, respectively, using upstream_not_ready and
upstream_busy so terminal error responses preserve the upstream reason.

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Inline comments:
Review comments at @packages/sie_gateway/src/queue/streaming.rs:
- Around line 363-366: Update client_safe_reason to admit parsed reasons only
when the failure code is an applicable inference or retryable upstream code;
return None for validation errors such as invalid_request.

---

Outside diff comments:
Review comments at @packages/sie_server/src/sie_server/adapters/remote/sie.py:
- Around line 767-770: Update the _terminal_chunk handling for MODEL_LOADING and
RESOURCE_EXHAUSTED events to pass upstream_reason when raising
GenerationDrainingError and GenerationCapacityError, respectively, using
upstream_not_ready and upstream_busy so terminal error responses preserve the
upstream reason.

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📒 Files selected for processing: 29

packages/sie_gateway/openapi.json
packages/sie_gateway/src/handlers/proxy.rs
packages/sie_gateway/src/handlers/serving_disclosure.rs
packages/sie_gateway/src/handlers/sse.rs
packages/sie_gateway/src/handlers/test_support.rs
packages/sie_gateway/src/openapi.rs
packages/sie_gateway/src/queue/publisher.rs
packages/sie_gateway/src/queue/streaming.rs
packages/sie_server/REMOTE_BACKENDS.md
packages/sie_server/openapi.json
packages/sie_server/src/sie_server/adapters/_generation_base.py
packages/sie_server/src/sie_server/adapters/errors.py
packages/sie_server/src/sie_server/adapters/remote/_chat_transport.py
packages/sie_server/src/sie_server/adapters/remote/_http.py
packages/sie_server/src/sie_server/adapters/remote/openai.py
packages/sie_server/src/sie_server/adapters/remote/sie.py
packages/sie_server/src/sie_server/api/generate.py
packages/sie_server/src/sie_server/api/openai_completions.py
packages/sie_server/src/sie_server/api/openai_local.py
packages/sie_server/src/sie_server/processors/remote_chat.py
packages/sie_server/src/sie_server/processors/streaming.py
packages/sie_server/src/sie_server/types/openapi.py
packages/sie_server/tests/adapters/test_remote_openai_generation.py
packages/sie_server/tests/adapters/test_remote_sie_generation.py
packages/sie_server/tests/api/test_remote_chat.py
packages/sie_server/tests/processors/test_remote_chat.py
packages/sie_server/tests/test_openapi_export.py
packages/wire-fixtures/README.md
packages/wire-fixtures/upstream_failure_reasons.json

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An SIE upstream that ends its stream before output with MODEL_LOADING or RESOURCE_EXHAUSTED now yields upstream_not_ready or upstream_busy, like the same answer as an HTTP status. The gateway admits a worker's reason only on inference_error, RESOURCE_EXHAUSTED and MODEL_LOADING, so a refusal of the caller's input never carries one.

krisztian-gajdar · 2026-10-15T13:44:00Z

Outside-diff finding on sie.py _terminal_chunk: fixed in d621d03. An SIE upstream that ends its stream before output with MODEL_LOADING or RESOURCE_EXHAUSTED now raises with upstream_not_ready or upstream_busy. test_a_retryable_terminal_event_before_output_carries_its_reason covers it, and removing the reason fails that test. Any other upstream terminal event keeps its existing path: an allowlisted terminal code with fixed text and no reason.

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…d own reason A remote generation failure now carries its reason on the paths the first round missed. A remote profile's timeout on a single node carries upstream_unavailable. An error object an upstream sends in place of an answer is classed by the status its code names, an SIE upstream's terminal error event and its error body keep the reason it names, and a final reason from an SIE upstream makes the failure final. A 403 with a known code is upstream_refused, a 408 upstream_unavailable and a final 429 upstream_busy. The error bodies are documented in the server's OpenAPI.

The wire fixture now carries the terminal error a worker publishes for an upstream that answered 402, which the worker test and the gateway decoder both check. The handler test also drives RESOURCE_EXHAUSTED and MODEL_LOADING terminals with their reasons.

…idges

krisztian-gajdar · 2026-10-15T15:22:36Z

Review round on 1a4e581a, fixed in 9efd357d, 0a7104ba and 7bb556db (head 7bb556db). An independent review of the whole change found the gaps below. Each one is fixed with a test or answered here.

Fixed

Timeouts had no reason. On a single node, a remote profile's first_chunk_timeout_s/overall_timeout_s now keeps its 504 and code and adds reason: upstream_unavailable. This covers native, completions, responses and rendered chat (generation_timeout). Rendered chat that times out after output ends with the same reason. A local profile's timeout still carries none. Tests: test_a_remote_profile_timeout_tells_the_caller_the_upstream_timed_out, the timeout case of test_an_upstream_failure_after_output_ends_the_stream_with_its_reason, and the assertion added to test_first_chunk_timeout_aborts_the_engine_and_returns_504.
An SIE upstream's terminal error event had no reason, and two classes for one failure.
- The terminal chunk now carries upstream_reason: the class the event names on inference_error, else upstream_unavailable, and upstream_busy or upstream_not_ready on RESOURCE_EXHAUSTED or MODEL_LOADING.
- Native, completions, responses, rendered chat (with and without tools) and the worker all carry it through, and the gateway forwards it.
- Rendered chat now uses the chunk's class instead of upstream_invalid_response, so one event has one class on every surface.
An in-band error was classed as a malformed answer. An error object sent in place of an answer ({"error":{"code":402,...}} as the body or as a stream event) is now classed by the status its numeric code names, and otherwise as upstream_unavailable. This covers the chat parser and the completions parser, before and after output.
The classification contradicted the table.
- A 429 with a final code (COLD_START_RATE_LIMITED) is now a final upstream_busy.
- A 408 is upstream_unavailable.
- A 403 with a known code (ACCOUNT_SUSPENDED, ACCOUNT_PENDING_REVIEW, THIRD_PARTY_*) is upstream_refused.
- The table and REMOTE_BACKENDS.md now say that the reason names the cause and the status says whether to retry.
SIE-to-SIE chaining lost the class. The SIE adapter reads the upstream's reason from its error body, its stream error event and its terminal event. A final class there makes the failure final here. Before, an SIE upstream's 500 inference_error naming upstream_payment_required was a retryable 503 upstream_unavailable.
The logging claim was overstated. An SIE upstream's terminal error event is now logged in the adapter as remote generation failed: upstream ended generation with <code> [<reason>], and the reported-error test asserts that line. REMOTE_BACKENDS.md now lists exactly what the adapter logs and what rendered chat logs.
The server OpenAPI documented reason only on the stream chunk. The native error detail (/v1/generate 500, which was undocumented, plus 503 and 504) and the OpenAI error body of chat, completions and responses now have schemas with reason.
Test gaps (a) to (g):
- (a) The leak matrix now includes rendered chat, buffered and streamed.
- (b) The connect case asserts the message.
- (c) The queued native-prompt test runs on both adapters, including the OpenAI-compatible completions endpoint.
- (d) The gateway handler test drives RESOURCE_EXHAUSTED and MODEL_LOADING terminals with their reasons, buffered (503 with Retry-After) and streamed.
- (e) A retryable terminal event before output is tested on every route.
- (f) A malformed event after output is tested.
- (g) The wire fixture now carries worker_terminal_error. The worker test produces exactly that object from a real 402, and the gateway test decodes the same object into its ChunkError.

Answered, documented in REMOTE_BACKENDS.md and the PR body

The gateway's own deadline carries no reason. It covers the queue wait, the worker and the upstream, so the gateway cannot tell whether the upstream was the slow hop. Attributing it to the upstream would be wrong for a queued or cold lane.
A bridged (fallback) request carries no reason. The failed remote attempt is answered with the original local refusal, unchanged (same status, body and Retry-After), as REMOTE_BACKENDS.md already specifies. The attempt's failure is named only in X-SIE-Fallback-Error, whose allowed values are pinned by serving_disclosure.json. Adding a remote reason to a local refusal's body would mislabel a local 503.
The transport_failure code, if an SIE upstream ends with it, keeps its code and carries no reason. The gateway forwards reasons only on inference_error, RESOURCE_EXHAUSTED and MODEL_LOADING, and the server follows the same rule.
Risks. The PR body now has the following:
- There is no override for the reason text or the field. I checked the server and gateway settings and ModelAccessPolicy, and none has a hook.
- A deployment that relays through its own upstream account exposes the class to its callers, including upstream_credential_unavailable.
- The gateway trusts a known reason from any worker, bounded to fixed text.
- GenerationUpstreamError replaces RemoteUpstreamError from generate(). Nothing in this repository depends on the old type.
- A queued native prompt logs a second WARNING, from the processor's existing traceback.
- An SIE upstream's final class now makes the failure final.
- The SDKs keep parsing code, message, param and retry_after_s only.

Validation is in the PR body. tests/api, tests/processors and tests/adapters of sie_server (7,481 passed), the full gateway-test (both feature sets), clippy, fmt, lint and typecheck all pass, and 30 new mutants were each caught.

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Inline comments:
Review comments at @packages/sie_server/src/sie_server/adapters/remote/_http.py:
- Around line 177-201: Update `upstream_error_reason` and its callers to parse
body `reason` values only when the upstream identified by `upstream` is
`UpstreamKind.SIE`; return no body reason for other upstream kinds. Preserve
existing status- and code-based mappings in `failure_for_status`.

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📥 Commits

Reviewing files that changed from the base of the PR and between 1a4e581 and 7bb556d.

📒 Files selected for processing: 24

packages/sie_gateway/src/handlers/serving_disclosure.rs
packages/sie_gateway/src/handlers/test_support.rs
packages/sie_gateway/src/queue/streaming.rs
packages/sie_server/REMOTE_BACKENDS.md
packages/sie_server/openapi.json
packages/sie_server/src/sie_server/adapters/_generation_base.py
packages/sie_server/src/sie_server/adapters/errors.py
packages/sie_server/src/sie_server/adapters/remote/_http.py
packages/sie_server/src/sie_server/adapters/remote/_openai_chat.py
packages/sie_server/src/sie_server/adapters/remote/_openai_completions.py
packages/sie_server/src/sie_server/adapters/remote/sie.py
packages/sie_server/src/sie_server/api/generate.py
packages/sie_server/src/sie_server/api/openai_completions.py
packages/sie_server/src/sie_server/api/openai_local.py
packages/sie_server/src/sie_server/api/openai_responses.py
packages/sie_server/src/sie_server/processors/remote_chat_prompt.py
packages/sie_server/src/sie_server/processors/streaming.py
packages/sie_server/src/sie_server/processors/tool_call_parser.py
packages/sie_server/src/sie_server/types/openapi.py
packages/sie_server/tests/api/test_generation_timeouts.py
packages/sie_server/tests/api/test_remote_chat.py
packages/sie_server/tests/processors/test_remote_chat.py
packages/wire-fixtures/README.md
packages/wire-fixtures/upstream_failure_reasons.json

🚧 Files skipped from review as they are similar to previous changes: 1

packages/wire-fixtures/README.md

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Krisztian Gajdar added 3 commits October 15, 2026 15:27

docs(server): document the reason of a remote generation failure

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krisztian-gajdar requested a review from a team as a code owner October 15, 2026 13:29

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Comment thread packages/sie_gateway/src/queue/streaming.rs Outdated

Krisztian Gajdar added 2 commits October 15, 2026 15:42

chore: merge origin/main

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Krisztian Gajdar added 3 commits October 15, 2026 17:15

docs(server): document the reason of timeouts, reported errors and br…

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krisztian-gajdar dismissed coderabbitai[bot]’s stale review via 7bb556d October 15, 2026 15:21

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krisztian-gajdar merged commit f52781a into main Oct 15, 2026
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krisztian-gajdar deleted the fix/upstream-refusal-reason branch October 15, 2026 15:58

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fix(api): tell the caller why a remote upstream refused, without naming it - #744

fix(api): tell the caller why a remote upstream refused, without naming it#744
krisztian-gajdar merged 8 commits into
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fix/upstream-refusal-reason

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Summary

How each failure is classed

Where the reason appears

What the caller does not see

Behaviour changes beyond the caller's body

Deployment note

Validation

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