#!/usr/bin/env node
/**
* mcp-steer - CLI tool for injecting steering messages into MCP Inspector sessions
*
* Usage:
* mcp-steer "your message here"
* mcp-steer --session sess_abc123 "your message"
* mcp-steer --list
*/
const STEERING_URL = "http://127.0.0.1:9847";
async function main() {
const args = process.argv.slice(2);
// Show help
if (args.length === 0 || args.includes("--help") || args.includes("-h")) {
console.log(`
mcp-steer - Inject steering messages into MCP Inspector sessions
Usage:
mcp-steer <message> Send steering to most recent session
mcp-steer -s <session_id> <msg> Send steering to specific session
mcp-steer --list List active sessions
mcp-steer --help Show this help
Examples:
mcp-steer "focus on error handling"
mcp-steer --session sess_abc123 "pause after this test"
mcp-steer -s sess_abc123 "check the logs"
`);
process.exit(0);
}
// List sessions
if (args.includes("--list") || args.includes("-l")) {
try {
const res = await fetch(`${STEERING_URL}/api/sessions`);
const data = await res.json();
if (data.count === 0) {
console.log("No active sessions");
} else {
console.log(`Active sessions (${data.count}):\n`);
for (const session of data.sessions) {
const idle = session.idleSeconds < 60
? `${session.idleSeconds}s`
: `${Math.floor(session.idleSeconds / 60)}m`;
console.log(` ${session.sessionId}`);
console.log(` Server: ${session.serverInfo?.name || 'unknown'}`);
console.log(` Idle: ${idle}`);
console.log();
}
}
} catch (error) {
console.error("Error: Could not connect to MCP Inspector");
console.error("Make sure the inspector is running with an active session.");
process.exit(1);
}
return;
}
// Parse session ID and message
let sessionId = undefined;
let message = "";
for (let i = 0; i < args.length; i++) {
if (args[i] === "--session" || args[i] === "-s") {
sessionId = args[i + 1];
i++; // skip next arg
} else if (!args[i].startsWith("-")) {
message = args.slice(i).join(" ");
break;
}
}
if (!message) {
console.error("Error: No message provided");
process.exit(1);
}
// Send steering
try {
const res = await fetch(`${STEERING_URL}/api/steer`, {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({ session_id: sessionId, message }),
});
const data = await res.json();
if (res.ok) {
console.log(`✓ Steering sent to ${data.session_id}`);
console.log(` Message: "${message}"`);
} else {
console.error(`Error: ${data.error}`);
process.exit(1);
}
} catch (error) {
console.error("Error: Could not connect to MCP Inspector");
console.error("Make sure the inspector is running with an active session.");
process.exit(1);
}
}
main();
