INVARA MCP server

<!-- mcp-name: io.github.Jujitae/invara -->

INVARA

Engineering invariants for AI-built software.

INVARA works with Claude Code, Codex, and any coding agent that can use a shell. It verifies declared constraints against observable evidence; it does not prove software correctness.

seal before work -> agent does the work -> judge
                                             |
                    PASS / BLOCK / UNVERIFIABLE / HUMAN_REVIEW

Start with the path that matches your environment:

/plugin marketplace add Jujitae/invara, then /plugin install invara.

• Claude Code: install the bundled editor/plugin experience with

uvx --from invara==0.3.0 invara list, or install persistently with python -m pip install invara==0.3.0.

• Codex or another shell-capable agent: run

AI Agent Quickstart, then preserve the exact verdict it receives.

• Tell your agent: use the copy-paste instructions in

The first result is a verdict, not an agent self-report. PASS means every declared check returned what it promised and protected paths stayed unchanged. BLOCK, UNVERIFIABLE, and HUMAN_REVIEW stay exactly that; none is success by reinterpretation.

Current public release: 0.3.0. Status: Alpha. INVARA Free is distributed publicly; INVARA Pro is a separate paid product. INVARA is not autonomous authorization and not an enterprise compliance control.

Transformation assurance in 0.3.0, Gen 1

Two local CLI workflows can now check a declared behavior envelope around a refactor or migration:

Manifest and can search for a minimized counterexample.

• invara assure compares an existing before/after pair under an Equivalence

after the declared checks accept it.

• invara repair governs a repair one unit at a time, keeping a unit only

Gen 1 measures only the inputs, observations, policies, and claims declared in the manifest. A PASS is bounded to that envelope; it is not a general proof of correctness, security, or bug-free software. The workflows run user-named commands with the user's permissions. They make no outbound network call; an HTTP probe may connect only to a loopback service that the manifest starts for the session.

Start with the CLI guide and the manifest guide. Synthetic examples and display reports are under fixtures/ and docs/transformation-assurance/samples/.

What this is not

Read this part before the install line. It is short on purpose, and the word that carries the promise above is verifiable — not correct.

INVARA does not prove software correctness.

It verifies declared constraints against observable evidence.

Specifically:

good, whether the architecture holds, or whether the tests are the right tests. Stack a new floor on junk and, if this floor was built to the declared spec, the verdict is PASS.

• It does not inspect your codebase. It never asks whether the code is

strong as your suite. INVARA reports the exit code; it does not have an opinion about coverage.

• It does not find bugs. A completion check that runs your suite is only as

contract. A weak contract earns a weak PASS, and the contract is stored verbatim so anyone can see how weak it was.

• It does not decide what should have been promised. You write the

your permissions. Do not seal a contract you have not read.

• It is not a sandbox. Completion checks are commands and they run with

work matched it. The checks are what bind.

• It does not judge intent. intent is prose; nothing checks that the

no model anywhere in the verdict path.

• It is not an AI code generator and not an LLM code-review bot. There is

The narrow claim, which is what the machine actually does:

It decides, independently, whether this change kept the promises it made.

CLI first verdict, in more detail

Shortened. The full README is on GitHub.