Model · Language model
Hermes 4 405B
Nous Research's August 2025 Hermes 4 hybrid-reasoning release at 405B parameters, fine-tuned from Llama-3.1-405B with toggleable think chains, tool use, and 131K context, published as open weights under the Llama 3.1 Community License with its acceptable-use policy. No developer API serves this exact model. Reviewed by automation under ADR 055 with human spot-checks; verify against the cited evidence.
- Developer
- Nous Research
- Distribution
- Downloadable weights
- Artifact licensing
- Restricted artifact terms
- License scope
- Reviewed release artifacts and mandatory terms; not an assessment of training code or training data openness.
- Licenses
- Llama 3.1 Community License · Llama 3.1 Acceptable Use Policy
- Boundary
- This record represents the Hermes-4-405B flagship of the Hermes 4 family. The 14B and 70B siblings, the Hermes 4.3 line, the Hermes 3 line, the base Llama-3.1-405B weights, the Hermes Agent system, and Portal-hosted agents are separate boundaries.
Risk statements
The developer publishes no risk-threshold statement for this release. Absence is not evidence of safety.
Page the reviewer checked ↗ · 2026-10-13 · Research confidence: High
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