Open Primitive

io.github.writesdavidPublished by GitHub account writesdavidv1.2.0Updated Oct 28, 2026

33 tools, 30 US federal data domains. Ed25519 signed, provenance chains, entity graph. Free.

The publisher's own server: Email

VerifiedSTDIODesktop onlyDeveloper ToolsData & Analytics

Overview

AI-generated overview

Local MCP server exposing US federal data domains through the Open Primitive Protocol, with signed, cited responses.

What you can do
  • Query US federal data domains (such as drug and adverse-event data) through the Open Primitive Protocol
  • Receive responses carrying domain, source, freshness, confidence and citation fields
  • Get Ed25519-signed responses with provenance chains and an entity graph
  • Use a client library, provider helper and validator for the protocol
When to use it
Useful when an assistant needs US federal public data with verifiable provenance and citations, or when you want to consume or validate Open Primitive Protocol providers from a local MCP client.
Requirements
Runs as a local stdio process, started for example with npx open-primitive-mcp, so Node.js and network access to the provider API are needed. No authentication, environment variables or headers are declared.
Before you install
The README and description disagree on the tool count (33 versus 13), so verify the actual tool set after installing. Data is fetched from a third-party API, so queries leave your machine; no credentials are requested.

Installation

In SourceWeft

  1. Open Open Primitive in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

Open Primitive Protocol (OPP)

The data layer of the agent internet.

OPP defines how data providers make their data agent-consumable, verifiable, and discoverable. Three components: provider manifest, response envelope, query interface.

The Problem

Agents get data naked. No provenance. No freshness guarantee. No confidence score. No way to verify the source. The agent internet is missing its data envelope.

The Protocol

ComponentWhat it does
Manifest (/.well-known/opp.json)Declares what data a provider serves, how fresh it is, how to verify it
Response EnvelopeEvery response carries domain, source, freshness, confidence, citation, Ed25519 signature
Query InterfaceStandardized HTTP GET endpoints with predictable parameters

Conformance Levels

  • Level 1 (Basic): Manifest + envelope with domain/source/freshness
  • Level 2 (Cited): Level 1 + confidence scores + citations
  • Level 3 (Verified): Level 2 + Ed25519 cryptographic proof

Reference Implementation

Live at api.openprimitive.com. 16 US federal data domains across 11 agencies. Level 3 compliant — every response is signed.

bash
curl https://api.openprimitive.com/v1/drugs?name=aspirin# Returns OPP envelope with proof.type: "DataIntegrityProof"

Quick Start

Use data from an OPP provider:

javascript
const res = await fetch('https://api.openprimitive.com/v1/drugs?name=aspirin');const data = await res.json();console.log(data.citations.statement);// "According to FDA FAERS, aspirin has 601,477 reported adverse events"

Implement OPP for your own data:

javascript
// 1. Create /.well-known/opp.json (see spec)// 2. Wrap responses in the OPP envelope// 3. Optionally sign with Ed25519

Specification

Full spec: openprimitive.com/protocol.html

Detailed spec: api.openprimitive.com/spec.html

SDK

  • sdk/opp-client.js — Client library for consuming OPP providers
  • sdk/opp-provider.js — Helper for implementing OPP
  • sdk/opp-validator.js — Validate OPP conformance

MCP Server

13 tools for Claude, Cursor, and MCP-compatible agents:

bash
npx open-primitive-mcp

Links

License

MIT

Source: README.md at commit 8f848c5

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

1
  1. v1.2.0LatestSep 16, 2026

Score

50% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts

    Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.

  • Auth declared10 pts

    Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.

  • Tools listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts

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Email

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