Clixad
Freemium
Developers who prefer terminal workflows
Code reviews catch logic errors late, tests miss edge cases, and formal correctness stays confined to academic papers — Forall exists for the gap between 'the tests pass' and 'the code is provably correct.'
Forall is an Apache-2.0 CLI agent from Astrio that generates spec-driven code alongside machine-checkable proofs, running entirely in your terminal or wiring into Cursor, Claude Code, or Codex via MCP. You describe what the code must do; the agent produces both the implementation and a formal proof you can verify independently. The verification step is not optional decoration — it runs against the spec, so a failing proof surfaces a real logical flaw before the code ships. The docs describe Rust, TypeScript, and Java as the supported targets, which covers a specific but meaningful slice of production codebases. Teams outside those languages hit a hard wall.
Bottom line: Pick Forall when you are building safety-critical Rust or TypeScript logic and need proof, not confidence — but if your stack is Python, Go, or anything outside the supported trio, the verification layer does not exist yet.
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Freemium
Developers who prefer terminal workflows
Freemium
Developers preferring fully local agent execution
Most confidence in code is probabilistic: tests pass, coverage looks good, the reviewer approved it. Forall takes a different position. The agent reads a specification, generates code against it, and produces a machine-checkable proof that the implementation satisfies the spec — not a lint warning, not a type hint, a formal mathematical proof. The workflow runs from the terminal via a CLI installed with a single curl command, or through an MCP config that plugs the same agent into editors like Cursor or Claude Code, giving teams the verification step inside the tool they already use.
The differentiating feature is the proof artifact itself. Most AI coding agents produce code you then trust or test. Forall produces code paired with a verifiable proof — meaning the correctness claim is checkable by a separate tool, not just by re-running the agent. The vendor describes this as spec-driven development with machine-checkable outputs, which shifts the debugging question from ‘did the tests catch it’ to ‘does the proof hold.’
Forall fits tightest into workflows where correctness is non-negotiable and the stack is Rust, TypeScript, or Java — financial logic, protocol implementations, security-critical parsing. It fits poorly when the project language sits outside those three, when the team has no existing culture around formal specifications, or when the spec-writing overhead outweighs the verification benefit for the task at hand. Teams doing rapid prototyping will find the proof generation step adds friction that serves no purpose until the code stabilizes.
The tool ships under Apache-2.0, self-hosts via the CLI, and exposes a hosted verification path through a FORALL_API_KEY. The MCP integration means the agent surfaces inside Cursor, Claude Code, or Codex without a separate context switch. The GitHub repo sits at astrio-labs/forall and includes an install.sh, examples directory, and a skills directory — the docs describe the agent behavior as autonomous, running specs-to-proof without manual step-by-step prompting.
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