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Mixed LF/CRLF SSE delimiters prevent Claude Code tool calls

Quick fix

Fix SSE delimiter parsing to recognize mixed LF/CRLF blank-line delimiters and preserve Claude Code tool-call events.

Symptom

Section titled “Symptom”
Error output
No `tool_use` block is produced.

Cause

Section titled “Cause”

`take_sse_block` recognizes only `\n\n` and `\r\n\r\n`, not `\n\r\n`, where the data line ends with LF and the blank line with CRLF. A complete SSE event is therefore not split immediately; when later events arrive, multiple events may also be merged into one block.

On the path converting OpenAI Chat Completions SSE to Anthropic SSE, this prevents a complete tool call containing the tool name, ID, argument fragments, and `finish_reason: "tool_calls"` from producing a `tool_use` block.

Fix

Section titled “Fix”

  1. Add `\n\r\n` and `\r\n\n` to the shared SSE delimiter list in `take_sse_block`, and continue selecting the earliest complete delimiter.

  2. Add framing tests for all four LF/CRLF delimiter combinations and transport chunks, plus a Chat Completions-to-Anthropic tool-call regression test.

Affected Versions

Section titled “Affected Versions”
ToolClaude Code
Version3.20.4（受影响）
PlatformsWindows

Source Issues

Section titled “Source Issues”

This page is distilled from 1 real issues

FAQ

Section titled “FAQ”

(No FAQ yet)

Section titled “Related problems”
<thinking> tags output as body text in Claude CodeChanging the provider's apiFormat from openai_chat to anthropic, if supported upstream, can bypass inline <thinking> leakage.1 issues mergedNo new usage record is createdMost related issues remain unresolved. Upgrade to a cc-switch version containing the #7740 fix for Gemini streaming usage parsing and model attribution.1 issues mergedIncorrect model displayed in Claude CodeConfigure a Custom Command for ccstatusline to read the model name from the current cc-switch provider configuration.1 issues merged

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