fix: emit text-start before completion to prevent first char being dropped #178
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…opped When streaming text responses, the first character or word was being dropped because text-start and text-delta were emitted synchronously in the same callback invocation. This caused the AI SDK to miss processing the first text-delta event. The fix emits text-start immediately after stream-start, before the completion callback begins, ensuring there's always an async boundary between text-start and the first text-delta. This matches the behavior of the apple-llm provider. Fixes #171
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grabbou
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Jan 24, 2026
…opped (#178) * fix: emit text-start before completion to prevent first char being dropped When streaming text responses, the first character or word was being dropped because text-start and text-delta were emitted synchronously in the same callback invocation. This caused the AI SDK to miss processing the first text-delta event. The fix emits text-start immediately after stream-start, before the completion callback begins, ensuring there's always an async boundary between text-start and the first text-delta. This matches the behavior of the apple-llm provider. Fixes #171 * chore: remove comments
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When streaming text responses, the
doStreammethod was emittingtext-startandtext-deltasynchronously in the same callback invocation (when the first token arrived). This caused the AI SDK to miss processing the firsttext-deltaevent because the initialization triggered bytext-startwasn't complete yet.The fix matches the behavior of the
apple-llmprovider, which emitstext-startimmediately when the stream is created, before any tokens arrive.Test Plan
streamTextwith llama provider - first character should no longer be missing<think>) to ensure they still work correctlyFixes #171