OpenAdmin 20B
OpenAdmin is the community model for Microsoft 365 administrators who want an open-source, local-first model. It is a fine-tune of gpt-oss-20b specialized for tenant administration work: planning Microsoft Graph calls with least-privilege scopes, drafting OpenAdminOS agent manifests, reasoning over device fleets, answering from retrieved Microsoft Learn documentation, and saying "not in the docs" instead of guessing.
It is built by OpenAdminOS, the open-source, local-first agent platform for Microsoft 365 admins, and ships as the default local model there. It runs on a single machine with 16 GB of memory in the MXFP4 quantization (see the GGUF repo).
Benchmarks
Scored on the OpenAdmin eval suite: 108 mechanically-scored tasks (schema validation, exact match, regex constraints; no LLM judges) across doc-grounded facts, abstention, Graph call planning (including held-out endpoints), agent-manifest drafting, fleet reasoning, and report voice. "With retrieval" pairs the model with a local index of Microsoft Learn documentation (Intune, Entra, Defender), which is how OpenAdminOS runs it.
| Model | No retrieval | With retrieval |
|---|---|---|
| gpt-oss-20b (base) | 49/108 (45%) | 73/108 (68%) |
| OpenAdmin 20B | 69/108 (64%) | 96/108 (89%) |
Category detail (with retrieval): doc facts 44/45, abstention 15/15, reasoning 21/23 (base: 11/23), Graph planning improved on both trained and held-out endpoints. Tasks and per-run results are published in openadmin-evals.
Training
QLoRA (rank 16) on 499 supervised examples, published in full at openadmin-sft. Every example is synthetic and machine-validated before admission: agent manifests are schema-validated, Graph plans come from a curated endpoint table, and reasoning examples carry mechanically-computed reasoning traces (the arithmetic is correct by construction). No tenant data, no scraped conversations, and no distillation from proprietary APIs were used at any point.
Intended use and limitations
Built for read-oriented administration assistance: queries, reports, classification, drafting. It is not a substitute for admin judgment; in OpenAdminOS every write to a tenant requires human confirmation regardless of what any model suggests, and we recommend the same posture elsewhere. The model inherits the general limitations of its 20B base; for current product or licensing facts, pair it with retrieval over current documentation rather than trusting parametric memory.
License
Apache 2.0, same as the base model. Base model copyright OpenAI; Microsoft, Intune, Entra, and Defender are trademarks of Microsoft Corporation, and this community project is not affiliated with or endorsed by Microsoft or OpenAI.
Files
The ready-to-run GGUF is available now in openadmin-20b-GGUF. Full-precision safetensors weights are being prepared and will be added to this repository shortly.