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GitHub Copilot streamed tool-call arguments are obfuscated, stalling agentic turns in Codex clients #989
Closed as not planned
Description
Activity
Automated translation bookkeeping — detected language: unknown.
Fix implemented and opened: #990
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Summary
GitHub Copilot's
/responseswire is not protocol-compatible with Responses clients for thevscode-chatintegration:response.function_call_arguments.deltaevents carry ciphertextdeltaplus anobfuscationfield.encrypted_content(GitHub's own scheme) with no plaintext summary; clients cannot decrypt them and stay stuck on "thinking".response.completedpayload disagrees with the streamed events (call_idis the only stable field).Impact
Any Responses-only Copilot model (
gpt-5.6-luna,gpt-5.6-sol,gpt-5.6-terra,gpt-5.4,gpt-5.4-mini,gpt-5.5,gpt-5.3-codex— see #748) stalls agentic turns in Codex clients: reasoning never finishes and tool calls are unreadable. Plain text works.Fix
Provider-scoped SSE rewrite for
github-copilot(PR #990): drop ciphertext deltas and re-emit plaintext arguments beforedone, neutralize encrypted reasoning items with an empty plaintext summary, and pin response/item ids to first-seen values.