DELTAX PREFLIGHT / FREE & OPEN SOURCE

Check the proposal.
Before the next step.

Give your agent an explicit policy boundary. Preflight checks proposed actions against the rules and evidence you supply—and makes unresolved choices visible.

Try the public walkthrough Connect Preflight ↓

Public preview · Apache-2.0 · No DeltaX account, API key, or subscription required. The walkthrough uses synthetic inputs and precomputed validator results.

MEET YOUR WORKFLOW WHERE IT IS

Three ways in.
One local validator.

Install locally to keep documents in your own environment. You choose the policy owner, trusted evidence source, and enforcement rules.

For agent workflows

Connect the MCP server.

Use the separate local MCP adapter in a compatible host. Node.js 20+ is required.

git clone https://github.com/DeltaX-Public/deltax-preflight.git
cd deltax-preflight
npm ci --prefix mcp --ignore-scripts

Point your host’s local server configuration at:

{
  "mcpServers": {
    "deltax-preflight": {
      "command": "node",
      "args": ["/absolute/path/to/deltax-preflight/mcp/bin/server.mjs"]
    }
  }
}

MCP setup & tool arguments

For scripts & applications

Start from the command line.

The npm core package includes the validator and worksheet. It does not install the MCP server.

npm install --global deltax-preflight
deltax-preflight-try --example

Core package on npm

For pull requests

Add a required review check.

Protect policy and evidence on the base branch, then configure the Preflight workflow check as required before merge.

Owner-reviewed GitHub gate

The local MCP tools are preflight_check, preflight_hash_decision, and preflight_hash_policy. They check supplied documents; they do not authenticate facts or execute a proposal.

A USEFUL RESULT, INCLUDING A STOP

Know what remains
before proceeding.

PASS_SINGLE

One admissible option.

Nothing is executed or authorized.

SELECTION_REQUIRED

Several admissible options.

Choose a human or separately authorized selection path.

REFUSE

No admissible option remains.

Stop this proposed path.

EVIDENCE_REQUIRED

Some evidence is unresolved.

Supply the missing evidence before a handoff.

WHEN YOU NEED BOUNDED SELECTION

Preflight first.
Evaluate by choice.

Only a SELECTION_REQUIRED result creates the optional handoff. Your adapter can minimize it into an Evaluate request, submit it with separate credentials, and reconcile the response against the admissible set.

Build the API handoff

Local checks stay independent.

Preflight MCP never calls Evaluate automatically. You can continue with a human reviewer and never subscribe. Builder adds the proposed paid API access, usage, and billing experience. Paid signup and checkout stay disabled until testing is complete.

Explore Builder

Public Preflight MCP is separate from the controlled hosted Evaluate MCP adapter. Neither selection nor a receipt grants execution authority.

OFFICIAL PROJECT & DISTRIBUTION

Choose a trusted
starting point.

Use the source and setup guides for current versions. A directory listing alone does not establish hosted availability.

Interactive Preflight walkthrough Synthetic scenarios with precomputed validator results · no account or download Official MCP Registry Active v0.1.0 entry · local MCPB distribution GitHub Marketplace Preflight Action for your own workflows Glama MCP directory Public listing · hosted availability is separate GitHub repository Source, examples, and documentation npm core package v0.1.1 · local CLI and JavaScript library MCP desktop bundle Separate v0.1.0 local MCPB release

Distribution checked November 3, 2026. The core npm package and MCP bundle are separate releases. Glama is a separate hosting boundary: review its data handling and release state before submitting documents; its listing is not a verified hosted service health check.

Check the proposal.Before the next step.

Three ways in.One local validator.