Some transient stream/rate-limit errors bypass retry and terminate sessions #21893

Description

When opencode hits certain transient upstream failures during model streaming, some failures are retried, but others terminate the session immediately. This breaks unattended runs.

Two examples I have seen:

{"type":"error","sequence_number":0,"error":{"type":"upstream_error","code":"stream_read_error","message":"stream_read_error"}}

Type validation failed: Value: ("error": ("type":"rate_limit_error","message":"concurrency limit exceeded for account, please retry later"))

From reading the code, the main session retry path only runs after an error has been normalized into a retryable MessageV2.APIError and accepted by SessionRetry.retryable(). These cases appear to fall through as unknown / validation errors instead, so the run stops instead of retrying.

Observed behavior:

• Known retryable failures such as some APICallErrors, ECONNRESET, and Bun decompression failures can enter session retry.
• Some stream-layer / wrapped validation failures with transient upstream semantics do not enter retry.
• The session ends in error/idle, and the task stops.

Expected behavior:

• Transient upstream stream errors should be normalized into the existing retry path.
• Wrapped rate-limit / concurrency-limit failures should still be recognized as retryable.
• Long unattended tasks should continue after these transient failures instead of stopping.

Potential code paths involved:

• packages/opencode/src/session/processor.ts
• packages/opencode/src/session/retry.ts
• packages/opencode/src/session/message-v2.ts
• packages/opencode/src/provider/error.ts
• packages/opencode/src/provider/sdk/copilot/chat/openai-compatible-chat-language-model.ts
• packages/opencode/src/provider/sdk/copilot/responses/openai-responses-language-model.ts

Plugins

None

OpenCode version

1.4.3 from source, current checkout ce19c051b

Steps to reproduce

1. Start a long-running agent task that streams model output.
2. Hit a transient upstream failure during streaming, especially one shaped like stream_read_error or a wrapped rate_limit_error / concurrency-limit validation error.
3. Observe that the session sometimes stops with an error instead of entering retry state.
4. Compare with already-classified retryable failures, which do enter retry state and continue.

Screenshot and/or share link

No share link. Error samples included above.

Operating System

Linux (WSL2) 6.6.87.2-microsoft-standard-WSL2

Terminal

xterm-256color