radiochron-mcp

radiochron.com · the chronicle of your radio.

A local-first Model Context Protocol server and command line for Wi-Fi incident diagnosis and Bluetooth Low Energy observation. It combines native radio collection with the radiochron Rust core, then returns typed conclusions instead of forcing an assistant to interpret raw operating-system output.

The two front ends are not two implementations. radiochron analyze and the wifi_analyze tool run the same handler with the same bounds and the same error text, so a conclusion never depends on how you asked for it.

The preferred MCP revision is 2025-11-25; clients that request 2025-06-18 receive the compatible legacy tool shape. Every tool has input and output schemas, structured content, safety annotations, explicit execution semantics, cancellation where work is long-running, and actionable separation between JSON-RPC protocol errors and tool execution errors.

RadioChron repositories remain independent:

• radiochron is the Rust/IoT core.
• radiochron-js is the Node/npm library; it does not ship MCP.
• radiochron-mcp is this pure-Rust MCP server and command line.
• radiochron-agent is the unattended durable collector/exporter and does not depend on MCP.
• radiochron-electron is the standalone desktop app and does not depend on MCP.

Install

The npm package carries verified native binaries for Windows x64, Linux x64/ARM64, Intel Mac, and Apple Silicon:

claude mcp add radiochron -- npx -y radiochron-mcp

Or install the Rust binary from source:

cargo install --git https://github.com/sergii-ziborov/radiochron-mcp

Building on Debian/Ubuntu requires libdbus-1-dev and pkg-config for the BlueZ adapter. Prebuilt npm users do not need a Rust toolchain.

Register an installed binary with any stdio MCP client:

{
  "mcpServers": {
    "radiochron": {
      "command": "radiochron"
    }
  }
}

RADIOCHRON_CHRONICLE_PATH optionally overrides the local chronicle path: %LOCALAPPDATA%\RadioChron on Windows, ~/Library/Application Support/RadioChron on macOS, or the XDG state directory on Linux.

Command line

The same binary is a CLI. Nothing extra to install — npx radiochron status works from the npm package, and cargo install puts radiochron on PATH.

radiochron status                  # association state of every adapter
radiochron scan                    # look again, then list what is there
radiochron analyze                 # findings about the environment
radiochron report                  # the full Markdown diagnostic report
radiochron incident --ble          # one composite answer for "the Wi-Fi is broken"
radiochron connectivity --dns example.com --tcp example.com:443
radiochron ble scan --duration 4000
radiochron chronicle recent --max 20
radiochron --help                  # every command and flag

Add --json to any command for the raw tool result, which is what a script wants:

radiochron networks --json | jq '.networks[] | select(.rssi_dbm > -60) | .ssid'

radiochron tool <name> [--args '<json>'] reaches any tool the catalogue publishes, including ones with no friendly spelling:

radiochron tool ble_evaluate --args '{"now_ms":1717000000000}'

Unknown flags are refused rather than ignored, so a mistyped --durations fails loudly instead of silently running with a default.

Running with no arguments still serves MCP over stdio, exactly as before, so every existing client configuration keeps working. A terminal on stdin means a person typed the name, and prints help instead; a pipe means a client, and speaks the protocol. radiochron mcp forces the server explicitly.

Two commands are CLI-only, because they have no session to live in: chronicle record runs the recorder in the foreground until you stop it, and chronicle path prints where the journal is kept.

MCP versus Node (radiochron-js)

They share one Rust core and one incident classifier. They are not stacked.

Desktop imports radiochron (npm) only. It must never spawn the MCP server for diagnosis — that would duplicate collectors and let cause logic drift.

Same verdict, two entry points

# MCP / CLI — orchestrates collectors, then core::incident::classify
radiochron doctor --json

// Node — same classifier, in-process native bridge
import { getRadioChronCoreClient } from 'radiochron';

const rc = getRadioChronCoreClient();
const report = await rc.diagnose({ includeBle: false });
console.log(report.assessment, report.causes);

// Optional: portable transfer matching MCP incident exports
import { createIncidentBundle, readIncidentBundle } from 'radiochron';

const bytes = createIncidentBundle({
  report,
  producer: {
    surface: 'node',
    surface_version: '0.7.0',
    core_version: '0.6.0'
  }
});
// write bytes to a .rchron file, or round-trip:
const again = readIncidentBundle(bytes);

An assistant that needs radio evidence should call MCP tools. An application that already runs Node should call radiochron directly and skip the MCP process entirely.

Start with one tool

Use diagnose_incident first (CLI alias: radiochron doctor). The tool orchestrates collectors and asks the shared core classifier for one incident verdict. The response keeps independent sections for:

• current Wi-Fi interfaces and association;
• RF/environment analysis;
• radio → authentication → DHCP → gateway → DNS → TCP → Internet stages;
• Windows WLAN event history when available;
• recent change-only chronicle entries;
• an optional native BLE advertisement scan, normalized identities, retained histories, and evidence-based findings.

One unavailable collector does not discard the rest of the incident. Each section has ok, data, or an actionable error, and the top-level problems list is compact enough for an assistant to explain directly. Targets are never contacted unless the caller supplies them.

Tool surface

Seventeen tools are portable. Windows exposes an eighteenth, wifi_history, backed by WLAN AutoConfig.

ble_scan uses WinRT on Windows, BlueZ on Linux, and CoreBluetooth on macOS. It listens only for devices observed during the requested scan window, does not perform GATT connections, and feeds the same privacy-minimized RadioChron tracker used by explicit ble_observe calls. iBeacon and Eddystone UID data can provide stronger protocol identity; generic private addresses remain ephemeral.

On macOS 11+, the host application or terminal launching the MCP process must have Bluetooth permission. An app bundle needs NSBluetoothAlwaysUsageDescription; a terminal-launched server requires Bluetooth access for that terminal in System Settings. Linux requires a running BlueZ service and access to the system D-Bus.

MCP behavior

• Newline-delimited UTF-8 JSON-RPC 2.0 over stdio; stdout contains MCP frames only.
• Negotiates both 2025-11-25 and 2025-06-18, preferring the current revision.
• Current tool definitions declare execution.taskSupport: "forbidden" because this local stdio server uses normal cancelable requests rather than durable experimental tasks.
• Unknown methods and malformed call envelopes use JSON-RPC errors.
• Tool input/radio/platform failures use isError: true so a model can correct arguments or explain the platform problem.
• Structured results are also serialized into text content for older clients.
• Source files are architecture-gated at 300 lines; real stdio conformance tests cover current and legacy lifecycle/catalog/error behavior.