| --- |
| license: mit |
| language: |
| - en |
| pretty_name: Serving-Stack Confounds in Local Tool-Use Evaluation |
| size_categories: |
| - n<1K |
| task_categories: |
| - text-generation |
| tags: |
| - tool-calling |
| - function-calling |
| - llm-evaluation |
| - llm-agents |
| - ollama |
| - vllm |
| - sglang |
| - llama-cpp |
| configs: |
| - config_name: serving_modes |
| default: true |
| data_files: serving_modes.csv |
| - config_name: chain_compare |
| data_files: chain_compare.csv |
| - config_name: crossstack |
| data_files: crossstack.csv |
| - config_name: humaneval_probe |
| data_files: humaneval_probe.csv |
| --- |
| |
| # Serving-Stack Confounds in Local Tool-Use Evaluation |
|
|
| Result tables for **Measuring the Serving Stack Instead of the Model: Hidden Confounds in |
| Local Tool-Use Evaluation** (Lijuan Tang, Yuemeng Zheng; REALM Workshop @ EMNLP 2026). |
|
|
| - Paper: [ACL Anthology](https://aclanthology.org/2026.realm-1.7/) · [arXiv:2609.26693](https://arxiv.org/abs/2609.26693) |
| - Code, configs, and reproduction steps: [github.com/LijuanTang94/serving-confound-repo](https://github.com/LijuanTang94/serving-confound-repo) |
|
|
|  |
|
|
| ## What this measures |
|
|
| **Protocol fidelity** = the rate of valid, in-schema tool calls over the turns the model |
| actually produced. Requests the server refused (for example Ollama's HTTP 400 |
| `does not support tools` for Phi-3 and Gemma-3) are counted separately as rejected and |
| excluded from the denominator. A naive analysis that counts them as model non-calls |
| reports a capable model at 0% even though it never ran. |
|
|
| Serving conditions: |
|
|
| | condition | `tools=` sent | text tool list in prompt | |
| |---|---|---| |
| | `native` (default) | yes | no | |
| | `native_hint` | yes | yes | |
| | `text_tools` / `tt` | no | yes | |
|
|
| All local models run on Ollama 0.30.8 with default (Q4_K_M) quantization; |
| `deepseek-v4-flash` is a cloud anchor. A "seed" indexes a task instance; decoding is |
| sampled at T=1.0. |
|
|
| ## Configs |
|
|
| ### `serving_modes` (default): aggregation task, 8 seeds, three conditions |
| |
| For each condition prefix (`native`, `native_hint`, `text_tools`): |
| |
| | column | meaning | |
| |---|---| |
| | `<cond>_seed` | per-seed mean fidelity | |
| | `<cond>_lo`, `<cond>_hi` | seed-level bootstrap 95% CI | |
| | `<cond>_pooled` | turn-pooled fidelity | |
| | `<cond>_n` | model-produced turns in the pool | |
| | `<cond>_rej` | rejected requests (excluded from the denominator) | |
| | `<cond>_n_seeds` | seeds with at least one produced turn | |
|
|
| Empty cells mean the condition was not run or the rate is undefined (every request was |
| rejected). |
|
|
| ### `chain_compare`: dependency-chain task, 4 seeds |
| |
| `native_*` and `tt_*` (text-tools) with `_seed` (per-seed mean), `_pool` (turn-pooled), |
| `_n` (turns), `_rej` (rejected requests). |
|
|
| ### `crossstack`: same `tools=` request on four serving stacks |
|
|
| One row per model; each cell is the outcome on that stack: `200_native` (native |
| `tool_calls`), `200_text` / `200_text_json_block` (call returned as text), |
| `200_runs_text` (request accepted, model runs), `200_prose_nocall` / `200_text_prose` |
| (prose, no call), `HTTP400_rejected` (Ollama per-model gating), `HTTP400_no_parser` |
| (vLLM without `--enable-auto-tool-choice --tool-call-parser`), `not_probed`, `n/a`. |
| `vllm_configured` is vLLM with tool parsing enabled. The vLLM and SGLang probes cover |
| only the models shown. |
|
|
| ### `humaneval_probe`: single-turn replication on 6 HumanEval problems |
| |
| `native_gating` is the Ollama response to `tools=` (`-` = not probed), then |
| `text_tools_valid` of `n` problems produced a valid call under the text-tools protocol. |
|
|
| ## Citation |
|
|
| ```bibtex |
| @inproceedings{tang-zheng-2026-measuring, |
| title = "Measuring the Serving Stack Instead of the Model: Hidden Confounds in Local Tool-Use Evaluation", |
| author = "Tang, Lijuan and |
| Zheng, Yuemeng", |
| booktitle = "Proceedings of the Second Workshop for {RE}search on Agent Language Models ({REALM} 2026)", |
| month = oct, |
| year = "2026", |
| address = "Budapest, Hungary", |
| publisher = "Association for Computational Linguistics", |
| url = "https://aclanthology.org/2026.realm-1.7/", |
| doi = "10.18653/2026.realm-1.7", |
| pages = "86--94" |
| } |
| ``` |
|
|
