feat(MODEL-XOR): juspay/xor MoE decision model with ForwardMoeHidden

[mudler-agent]

MODEL-XOR: juspay/xor MoE decision model

xor (juspay/xor) is a 35B MoE System 1 decision model from Qwen3.6-35B-A3B (~3B activated). Text-only Phase 1 path.

Key new infrastructure

• ForwardMoeHidden: new single-sequence hidden-state extraction for the MoE backbone, mirroring ForwardDenseHidden (dense) but calling RunLayer (MoE) instead of RunDenseLayer. Returns [T, H] f32 post-final-norm hidden states with NO lm_head.
• Forward+reverse option-order evaluation: runs the decision forward twice (original and reversed option order), then calibrates by averaging probabilities.

Architecture

• Decision pipeline: build prompt → forward MoE backbone (ForwardMoeHidden) → extract last-token hidden → apply lm_head for candidate logit readout → forward+reverse → calibrate
• Arch name: "XorModel"
• Reuses Qwen3.5 MoE weights (LoadQwen3_5Moe) and config (ParseQwen3_5Config, MakeQwen3_5KVCache)

New files

• include/vllm/model_executor/models/xor.h — head params, declarations
• include/vllm/model_executor/models/xor_inference.h — XorDecisionResult + XorInference()
• src/vllm/model_executor/models/xor_registry.cpp — factory, load, prepare, forward, inference, registration
• tests/vllm/models/test_xor.cpp — 10 tests, 17 assertions (all pass)

Modified

• include/vllm/model_executor/models/qwen3_5.h — declare ForwardMoeHidden
• src/vllm/model_executor/models/qwen3_5.cpp — implement ForwardMoeHidden
• CMakeLists.txt — add xor_registry.cpp
• tests/CMakeLists.txt — add test_xor
• src/capi/vllm_c.cpp — allowlist XorModel + XorInference dispatch in vllm_decide
• src/vllm/entrypoints/openai/server_main.cpp — XorModel decision dispatch block

Spec

.agents/specs/xor.md

FOLLOWING_AGENTS_PROTOCOL
Following-Agents-Protocol: true
AI-Assisted: true
Assisted-by: AGENT:glm5.2 [nib]

[mudler-agent]

Closing: the model implementation, tests, and docs from this PR were merged to main via #3324 (feat/parakeet-diarization). All model files are on main: clm_head.cpp, clm_registry.cpp, gliner25_decide_head.cpp, gliner25_decide_registry.cpp, xor_registry.cpp, tev1_registry.cpp, and all test files. E2E verified: CLM, GLiNER2.5-Decide, and Tev1-4B all load and serve correctly.