fix: translate "developer" role to "system" for chat template compatibility#20079
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marksverdhei wants to merge 1 commit intoggml-org:masterfrom
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fix: translate "developer" role to "system" for chat template compatibility#20079marksverdhei wants to merge 1 commit intoggml-org:masterfrom
marksverdhei wants to merge 1 commit intoggml-org:masterfrom
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…bility OpenAI's Responses API uses "developer" as an alias for "system", but llama.cpp passed this role through verbatim to Jinja chat templates. Templates that validate roles strictly (e.g. Qwen3.5 MoE) crashed with "Unexpected message role", while permissive templates silently lost the system prompt. Changes: - common/chat.cpp: remap developer→system in common_chat_msgs_parse_oaicompat() - server-common.cpp (chat completions): remap on raw JSON messages before template parsing - server-common.cpp (responses API): remap developer→system and merge with any existing system message from the "instructions" field to avoid duplicate system messages that trigger "System message must be at the beginning" errors Fixes Codex CLI + Qwen3.5-35B-A3B and any other model with strict template role validation. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
This was referenced Mar 24, 2026
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Summary
"developer"as an alias for"system", but llama.cpp passed this role through verbatim to Jinja chat templatesraise_exception('Unexpected message role.'), while permissive templates silently lost the system promptdeveloper→systemremapping in three places:common_chat_msgs_parse_oaicompat(), the chat completions message loop, and the Responses API conversion layerinstructions-derived system message to prevent duplicate system messages that trigger "System message must be at the beginning" template errorsTest plan
POST /v1/chat/completionswithrole: "developer"+ tools returns 200 (was 500)POST /v1/responseswithinstructions+developerrole input + tools returns 200 (was 500)wire_api = "responses") works end-to-end with Qwen3.5🤖 Generated with Claude Code