Retell AI runs on your own machine — the client starts it, so there is no endpoint to ping. 104 installs a week from npm. Last commit 13 Sep 2026.
Retell AI MCP server: voice agent phone calls, agent management, LLMs, and voice discovery
We read the source, 21 h ago · rules 3dff92dd89df
A value the model can set ends up inside a file or shell call. That is not a flaw by itself — for a terminal server it is the job — but it is where things go wrong when it is not.
fs.writeFileSync(outFd, pdfBuffer);
What this server is able to do. For an MCP server this is often the job itself — a terminal server runs commands because that is what it is for. Listed so you know what you are plugging in, not as an accusation.
const fullPath = path.join(stagingDir, filename);
const child = spawn(process.execPath, [script], {
if (isUnder(resolvedAbs, sshDir)) return { hit: true, reason: '~/.ssh/** is sensitive' };
<script src="https://appsforoffice.microsoft.com/lib/1.1/hosted/office.js"></script>
const entries = fs.readdirSync(workspacePath, { withFileTypes: true });
Is this your server and something here is wrong? Tell us — corrections are free and do not require a plan.
That is not a flaw by itself — but it is where things go wrong when it is not the job. We re-read this code on every release. Watch it and you hear from us the day another one appears.
This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.
claude mcp add mcp-server-retell-ai -- npx -y @mindstone/mcp-server-retell-ai
{
"mcpServers": {
"mcp-server-retell-ai": {
"args": [
"-y",
"@mindstone/mcp-server-retell-ai"
],
"command": "npx"
}
}
}
[mcp_servers.mcp-server-retell-ai]
command = "npx"
args = ["-y", "@mindstone/mcp-server-retell-ai"]
{
"mcpServers": {
"mcp-server-retell-ai": {
"args": [
"-y",
"@mindstone/mcp-server-retell-ai"
],
"command": "npx"
}
}
}
{
"mcpServers": {
"mcp-server-retell-ai": {
"args": [
"-y",
"@mindstone/mcp-server-retell-ai"
],
"command": "npx"
}
}
}
This one needs environment variables set before it will start:
RETELL_API_KEY (Retell AI API key (from retellai.com/dashboard)), MCP_WORKSPACE_PATH (Optional workspace directory for local files uploaded as knowledge-base sources. File reads are sandboxed to this directory (defaults to the system temp directory when unset).).
The author declared them in the registry entry; get the values from the project itself.
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