Open Math Harness is the open-source runtime of Open Math OS, and this repository holds its kernel, services and agents, written in Rust. Its first generation is named Nucleus.

Open Math OS is infrastructure for Math 2.0: the operating system for collaborative math research, with open frontier models, a scientific compute cloud and collaboration tools in one system, and the mathematical community in control of its data.

On Open Math OS, Open Math Harness runs agents on open models, parallel exploration with Ultramath and proofs checked by Lean. Its capability-based microkernel holds every agent to the authority it was given: agents propose, mathematicians decide.

Apply for a team on Open Math OS.

Open Math Harness is developed as the runtime of Open Math OS. We publish its source so that its design and implementation can be inspected, studied and built on.

We plan to reduce these deployment dependencies and make individual components easier to run independently in future releases.

• Agents on open models. Every chat has an agent on the open-weight model and the reasoning depth chosen for the task, with streaming replies, tool use, sub-agents and persistent session history.
• Ultramath. Several agents explore different approaches to one hard problem and bring their findings back to the chat. You decide what holds.
• Proof search. A tree search over candidate proofs of a fixed Lean statement, with confined prover agents working its branches in parallel.
• Proofs checked by Lean. Every candidate is checked by Lean in a confined workspace, with a deadline. Whether a proof holds is decided by Lean, never by what a model says about it.
• Tools and memory for every project. Projects are git repositories. Agents work with files and the shell, web and PDF tools, the project's skills, MCP servers (stdio and Streamable HTTP) and plugins they build, and keep a project memory across sessions.
• People in charge. A protected action waits for a person's approval, and a session's records are scanned for secrets before the platform shows them.

Agents propose; mathematicians review and decide. Open Math Harness is designed so that this holds in the runtime, not only in the prompts:

• Every program, agents included, is a confined process that holds only the capabilities its composition grants it, and what it starts receives no more.
• Model output, tool results and repository content are untrusted input. Text cannot grant authority, approve an action or decide a verification result.
• Credentials stay with narrowly privileged providers. They never reach a model, a transcript or a log.
• Agent loops, model providers, tools and memory are replaceable services. The kernel keeps only the mechanisms every service must share: identity, capabilities, IPC and lifetimes.

AGENTS.md states these requirements; each module's docs say what its code guarantees.

Ultramath coordinates multiple agents exploring different approaches to a hard problem. Each member registers a proposed direction, which a model-based duplicate check compares against other registered directions. Members share lemmas, partial results, counterexamples and unsuccessful approaches on a common board, and keep their working files in separate directories.

Exploration runs asynchronously alongside the conversation. Members submit reports and supporting files to the coordinating agent for review. The coordinator can return feedback for revision or accept a solution, which stops the remaining members. The run records directions, findings and review decisions for later inspection.

Proof search starts from a fixed Lean statement and preserves candidate proofs in a tree. An exploration policy selects which saved workspaces to continue, and workers explore those branches in parallel. The harness evaluates submitted candidates through the Lean verifier and records the results, so later rounds can build on earlier work.

The discovery interface manages runs and exposes their progress and search trees. The explore interface gives each worker its assignment, lets workers share research plans, and receives their candidates. A proof counts as solved only when it passes verification against the original statement.

Memory is maintained per project. After a session becomes quiet, the memory service extracts material from its history and consolidates selected material into MEMORY.md. Later sessions receive that memory as context and cite what they use; citation history helps select material for future consolidation. Memory carries no authority to grant permissions or override the user's current instructions.

• Linux, with a C compiler and linker for native dependencies. Windows and macOS are not supported as native runtime hosts.
• Rust installed through rustup. rust-toolchain.toml pins the toolchain and includes the formatting and linting components.
• bubblewrap, with bwrap on PATH and permission to create unprivileged user namespaces. Host security policy must allow bubblewrap to create its sandbox; startup fails if confinement is unavailable.

git clone https://github.com/openmathmodel/open-math-harness.git
cd open-math-harness
cargo build --locked --workspace

This builds the launcher and service binaries into target/debug/.

Running interactive agents additionally requires a service configuration, model provider credentials and a client. Proof search also requires a configured Lean and Mathlib environment. The files in deploy/vm/ target the managed Open Math OS VM and are not a standalone installer for a personal machine.

The slice example runs a scripted agent, a worker and a filesystem service to demonstrate capability checks and delegation. It does not call a model or start interactive chat, Ultramath, memory or proof search. It needs no model credentials or Open Math OS deployment, but still requires Linux and working bubblewrap confinement. After building, run this command from the repository root:

cargo run --locked --manifest-path cli/Cargo.toml -- run examples/slice/config.json

The agent reads permitted files, delegates access to a smaller directory to its worker, and attempts operations that the kernel refuses. Calls and results are recorded in examples/slice/out/agent/transcript.jsonl and examples/slice/out/agent/worker/transcript.jsonl. The filesystem service records the calls it receives in examples/slice/log/access.jsonl.

The example also creates examples/slice/data/work/report.txt. To repeat that creation successfully, remove the generated report before running the example again.

Run the Rust tests from the repository root after building:

cargo test --workspace

The default tests require no paid model API or production credentials. Integration tests exercise real child processes and bubblewrap; tests requiring external providers or a Lean installation are explicitly opt-in.

The CI workflow defines the full checks and their environment, including formatting, Clippy, Python tooling tests and Node.js MCP integration tests. See CONTRIBUTING.md for contribution requirements, including AI review, testing and the information to include in a pull request.

We welcome discussion and contributions. Join the Open-Math-Model channel on the SAIR Foundation Zulip, and see Community discussion for how to take part.

Open Math Harness is licensed under the Apache License 2.0. Attributions and license terms for incorporated third-party material are in third-party/NOTICES.txt.

The current release is Open Math Harness 0.41.0, the Nucleus generation.