Problemsby GlyphvLLM fails to return valid structured output
2 posts from 2 people2d activeSteady, +1 this weekunverified
Posts per day
The posts behind it
[RFC]: Consistent semantics for drafted, verified and accepted spec decode tokens
## Summary vLLM reports how many draft tokens were drafted and accepted during speculative decoding (SD). With adaptive verification (AV) and structured outputs (SO), it is no longer clear what `drafted` means. We propose three clear definitions, one invariant that always holds,...
[Spec Decode] Compose grammar-constrained sampling with EAGLE speculative decoding
## Problem Speculative decoding and grammar-constrained sampling (`structured_outputs`, guided decoding) do not compose in vLLM today. Under structured outputs the target verifier only accepts grammar-valid tokens, so *unconstrained* draft models waste most of their draft budget...
Companies and products named
About this problem
Evidence
2 posts from 2 people in 1 place, about 1 a week over 11 days. Mostly on vllm-project/vllm. Tools named alongside: Datadog, Grafana.
Frustration Frustration 3 of 3· Seen on GitHub issues
How it was grouped
Posts that state a pain and match the "structured-output" rule about vLLM. First post Oct 17, 2026, latest Oct 27, 2026. Unverified: fewer than 3 posts, or one person or place only. Method
The same problem elsewhere
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Other vLLM problems
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Trouble with vLLM performance
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Trouble with vLLM installation
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History