Continuously monitoring 259 active endpoints

LLM API outputs are unstable over time.

LLM APIs are opaque black boxes, even for open-weight models. TrackLLM continuously monitors them for undisclosed changes — cheaply — with logprob tracking (LT) where logprobs are exposed, and black-box border input tracking (B3IT) where they aren't. Small changes are fine, but they should be disclosed.

Endpoints monitored
809
259 active · 550 retired · 1,707 in the catalog
Models tracked
262
across 53 orgs
Providers
77
178 serving variants
Queries logged
15.1M
since Jun 2025
Changes detected
186
77 LT · 109 B3IT

Inria IRISA CNRS
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Latest changes

how far each endpoint moved from its baseline All 186 changes →
5 Sep
Probe-prompt outputs shifted (total variation 0.28)
B3IT
4 Sep
Probe-prompt outputs shifted (total variation 0.34)
B3IT
3 Sep
Probe-prompt outputs shifted (total variation 0.55)
B3IT
2 Sep
Probe-prompt outputs shifted (total variation 0.34)
B3IT
1 Sep
Probe-prompt outputs shifted (total variation 0.34)
B3IT
1 Sep
Probe-prompt outputs shifted (total variation 0.75)
B3IT
1 Sep
Probe-prompt outputs shifted (total variation 0.55)
B3IT
1 Sep
Logprob averages moved 7.18 nats from baseline
LT
1 Sep
Probe-prompt outputs shifted (total variation 0.34)
B3IT
29 Aug
Probe-prompt outputs shifted (total variation 0.52)
B3IT
More…

Providers

detected changes per endpoint-year of LT monitoring All 77 providers →
More…

Endpoints

809 endpoints monitored, of 1,707 in the catalog · 186 changes across 147 endpoints All endpoints →
Endpoint Status Changes Methods Last change Drift from baseline
hy3atlas-cloud/fp8changed 3 B3IT 28 Aug
deepseek-v4-flash-0731streamlake/fp8changed 2 B3IT 1 Sep
deepseek-v4-procoreweave/fp8changed 2 LTB3IT 20 Aug
glm-5.2cloudflarechanged 2 B3IT 14 Aug
glm-5.2decart/fp4changed 2 B3IT 11 Aug
glm-5.2togetherchanged 2 B3IT 24 Aug
glm-5.2z-ai/fp8changed 2 B3IT 19 Aug
gpt-4o-2024-05-13azurechanged 2 LT 21 May
gpt-4o-miniazurechanged 2 LTB3IT 23 May
hy3deepinfra/fp8changed 2 B3IT 20 Aug
More…

Timothée Chauvin, Erwan Le Merrer, François Taïani, Gilles Tredan (2026), "Log Probability Tracking of LLM APIs". ICLR 2026. https://arxiv.org/abs/2512.03816

Timothée Chauvin, Clément Lalanne, Erwan Le Merrer, Jean-Michel Loubes, François Taïani, Gilles Tredan (2026), "Token-Efficient Change Detection in LLM APIs". ICML 2026. https://arxiv.org/abs/2602.11083

@inproceedings{
chauvin2026log,
title={Log Probability Tracking of {LLM} {API}s},
author={Timothee Chauvin and Erwan Le Merrer and Francois Taiani and Gilles Tredan},
booktitle={The Fourteenth International Conference on Learning Representations},
year={2026},
url={https://openreview.net/forum?id=hFxivbAgVP}
}

@inproceedings{
chauvin2026tokenefficient,
title={Token-Efficient Change Detection in {LLM} {API}s},
author={Timothee Chauvin and Cl{\'e}ment Lalanne and Erwan Le Merrer and Jean-Michel Loubes and Francois Taiani and Gilles Tredan},
booktitle={Forty-third International Conference on Machine Learning},
year={2026},
url={https://openreview.net/forum?id=7cMlZZYZT0}
}