$0.16

per minute, AI processing

< 1.2s

typical AI response latency

2,000+

companies in production

0

vendor hops per turn

The five-vendor problem

What the Multi-Vendor Stack Costs You

Integration overhead that never ends

Weeks of glue code to connect five APIs, handle format mismatches, and manage WebSocket lifecycle. Every vendor API change, deprecation, or rate limit adjustment requires engineering attention.

Cross-provider debugging at 2am

An alert fires. Callers hear silence. Each vendor says their service is healthy. Four hours of log correlation across three time zones before you discover the TTS provider ran out of characters three days ago.

Double-billing and race conditions

Mixing telephony and orchestration vendors creates overlapping charges and timing conflicts. Multiple providers meter the same minutes from different angles.

Five contracts, five SLAs, zero accountability

When something breaks in the gap between vendors, nobody is responsible. Each vendor points at the others. Your team absorbs the incident.

Five vendors vs. one platform

Typical Voice AI Stack

Telephony from one provider
STT from another provider
TTS from a third provider
LLM from a fourth provider
Orchestration from a fifth provider
Five invoices, five failure domains, zero unified logs

SignalWire

Telephony, STT, TTS, and LLM orchestration in one media engine
One invoice, one set of logs, one support channel
No WebSocket piping between vendors
Sub-second AI response latency (800-1200ms typical)
Built by the team that wrote FreeSWITCH

Build a Voice AI Agent

from signalwire_agents import AgentBase
from signalwire_agents.core.function_result import SwaigFunctionResult

class SupportAgent(AgentBase):
    def __init__(self):
        super().__init__(name="Support Agent", route="/support")
        self.prompt_add_section("Instructions",
            body="You are a customer support agent. "
                 "Greet the caller and resolve their issue.")
        self.add_language("English", "en-US", "rime.spore:mistv2")

    @AgentBase.tool(name="check_order")
    def check_order(self, order_id: str):
        """Check the status of a customer order.

        Args:
            order_id: The order ID to look up
        """
        return SwaigFunctionResult(f"Order {order_id}: shipped, ETA April 2nd")

agent = SupportAgent()
agent.run()

import { AgentBase, FunctionResult } from '@signalwire/sdk';

const agent = new AgentBase({
  name: 'Support Agent',
  route: '/support',
});

agent.promptAddSection('Instructions',
  'You are a customer support agent. Greet the caller and resolve their issue.');

agent.addLanguage({ name: 'English', code: 'en-US', voice: 'rime.spore:mistv2' });

agent.defineTool({
  name: 'check_order',
  description: 'Check the status of a customer order',
  parameters: {
    type: 'object',
    properties: {
      order_id: { type: 'string', description: 'The order ID to look up' },
    },
    required: ['order_id'],
  },
  handler: (args) => {
    return new FunctionResult(`Order ${args.order_id}: shipped, ETA April 2nd`);
  },
});

agent.run();

package main

import (
	"fmt"

	"github.com/signalwire/signalwire-go/pkg/agent"
	"github.com/signalwire/signalwire-go/pkg/swaig"
)

func main() {
	a := agent.NewAgentBase(
		agent.WithName("Support Agent"),
		agent.WithRoute("/support"),
	)

	a.PromptAddSection("Instructions",
		"You are a customer support agent. Greet the caller and resolve their issue.")

	a.AddLanguage(map[string]any{
		"name": "English", "code": "en-US", "voice": "rime.spore:mistv2",
	})

	a.DefineTool(agent.ToolDefinition{
		Name:        "check_order",
		Description: "Check the status of a customer order",
		Parameters: map[string]any{
			"type": "object",
			"properties": map[string]any{
				"order_id": map[string]any{
					"type": "string", "description": "The order ID to look up",
				},
			},
			"required": []string{"order_id"},
		},
		Handler: func(args map[string]any, rawData map[string]any) *swaig.FunctionResult {
			orderID := args["order_id"]
			return swaig.NewFunctionResult(
				fmt.Sprintf("Order %v: shipped, ETA April 2nd", orderID),
			)
		},
	})

	a.Run()
}

import com.signalwire.sdk.agent.AgentBase;
import com.signalwire.sdk.swaig.FunctionResult;

import java.util.List;
import java.util.Map;

public class SupportAgent {
    public static void main(String[] args) throws Exception {
        var agent = AgentBase.builder()
                .name("Support Agent")
                .route("/support")
                .build();

        agent.promptAddSection("Instructions",
                "You are a customer support agent. "
              + "Greet the caller and resolve their issue.");

        agent.addLanguage("English", "en-US", "rime.spore:mistv2");

        agent.defineTool(
                "check_order",
                "Check the status of a customer order",
                Map.of("type", "object",
                       "properties", Map.of(
                           "order_id", Map.of(
                               "type", "string",
                               "description", "The order ID to look up")),
                       "required", List.of("order_id")),
                (toolArgs, rawData) -> {
                    var orderId = toolArgs.get("order_id");
                    return new FunctionResult(
                        "Order " + orderId + ": shipped, ETA April 2nd");
                }
        );

        agent.run();
    }
}

# frozen_string_literal: true

require 'signalwire'

agent = SignalWire::AgentBase.new(name: 'Support Agent', route: '/support')

agent.prompt_add_section('Instructions',
  'You are a customer support agent. Greet the caller and resolve their issue.')

agent.add_language(name: 'English', code: 'en-US', voice: 'rime.spore:mistv2')

agent.define_tool(
  name:        'check_order',
  description: 'Check the status of a customer order',
  parameters:  {
    'order_id' => { 'type' => 'string', 'description' => 'The order ID to look up' }
  }
) do |args, _raw|
  SignalWire::Swaig::FunctionResult.new(
    "Order #{args['order_id']}: shipped, ETA April 2nd"
  )
end

agent.run

<?php
require 'vendor/autoload.php';

use SignalWire\Agent\AgentBase;
use SignalWire\SWAIG\FunctionResult;

$agent = new AgentBase(['name' => 'Support Agent', 'route' => '/support']);

$agent->promptAddSection('Instructions',
    'You are a customer support agent. Greet the caller and resolve their issue.');

$agent->addLanguage('English', 'en-US', 'rime.spore:mistv2');

$agent->defineTool(
    name: 'check_order',
    description: 'Check the status of a customer order',
    parameters: [
        'order_id' => ['type' => 'string', 'description' => 'The order ID to look up'],
    ],
    handler: function (array $args): FunctionResult {
        return new FunctionResult("Order {$args['order_id']}: shipped, ETA April 2nd");
    }
);

$agent->run();

#!/usr/bin/env perl
use strict;
use warnings;
use lib 'lib';
use SignalWire::Agent::AgentBase;
use SignalWire::SWAIG::FunctionResult;

my $agent = SignalWire::Agent::AgentBase->new(
    name  => 'Support Agent',
    route => '/support',
);

$agent->prompt_add_section('Instructions',
    'You are a customer support agent. Greet the caller and resolve their issue.');

$agent->add_language(name => 'English', code => 'en-US', voice => 'rime.spore:mistv2');

$agent->define_tool(
    name        => 'check_order',
    description => 'Check the status of a customer order',
    parameters  => {
        order_id => { type => 'string', description => 'The order ID to look up' },
    },
    handler => sub {
        my ($args, $raw) = @_;
        return SignalWire::SWAIG::FunctionResult->new(
            response => "Order $args->{order_id}: shipped, ETA April 2nd"
        );
    },
);

$agent->run;

#include <signalwire/agent/agent_base.hpp>

using namespace signalwire;
using json = nlohmann::json;

class SupportAgent : public agent::AgentBase {
public:
    SupportAgent() : AgentBase("Support Agent", "/support") {
        prompt_add_section("Instructions",
            "You are a customer support agent. "
            "Greet the caller and resolve their issue.");

        add_language({"English", "en-US", "rime.spore:mistv2"});

        define_tool({
            .name = "check_order",
            .description = "Check the status of a customer order",
            .parameters = {
                {"order_id", {{"type", "string"},
                              {"description", "The order ID to look up"}}}
            },
            .handler = [](const json& args, const json&) {
                auto order_id = args.value("order_id", "unknown");
                return swaig::FunctionResult(
                    "Order " + order_id + ": shipped, ETA April 2nd");
            }
        });
    }
};

int main() {
    SupportAgent().run();
}

using SignalWire.Agent;
using SignalWire.SWAIG;

var agent = new AgentBase(new AgentOptions { Name = "Support Agent", Route = "/support" });

agent.PromptAddSection("Instructions",
    "You are a customer support agent. Greet the caller and resolve their issue.");

agent.AddLanguage("English", "en-US", "rime.spore:mistv2");

agent.DefineTool("check_order", "Check the status of a customer order",
    new { type = "object", properties = new {
        order_id = new { type = "string", description = "The order ID to look up" }
    }, required = new[] { "order_id" } },
    (args, rawData) =>
    {
        var orderId = args.TryGetValue("order_id", out var id) ? id : "unknown";
        return new FunctionResult($"Order {orderId}: shipped, ETA April 2nd");
    });

agent.Run();

use signalwire::agent::AgentBase;
use signalwire::swaig::FunctionResult;
use serde_json::json;

fn main() {
    let mut agent = AgentBase::builder()
        .name("Support Agent")
        .route("/support")
        .build();

    agent
        .prompt_add_section("Instructions",
            "You are a customer support agent. Greet the caller and resolve their issue.", &[])
        .add_language("English", "en-US", "rime.spore:mistv2");

    agent.define_tool(
        "check_order",
        "Check the status of a customer order",
        json!({"type": "object", "properties": {
            "order_id": {"type": "string", "description": "The order ID to look up"}
        }, "required": ["order_id"]}),
        Box::new(|args, _raw| {
            let order_id = args.get("order_id").and_then(|v| v.as_str()).unwrap_or("unknown");
            FunctionResult::with_response(&format!("Order {order_id}: shipped, ETA April 2nd"))
        }),
    );

    agent.run();
}

Real numbers

Metric	Five-Vendor Stack	SignalWire
Per-minute cost	$0.20-$0.33 all-in	$0.16/min all AI components
Invoices	5	1
Typical AI response latency	950ms-3,000ms	800-1200ms
Vendor hops per turn	6+	0
Time to production	Months	Days
2am incident resolution	Hours (cross-provider)	Minutes (single log)

The migration path

1

Start with one agent

Define a voice AI agent in YAML or Python. Point a phone number at it. Test against your existing stack.

2

Compare side by side

Measure latency, reliability, and cost. SignalWire delivers 800-1200ms typical response latency because there are no vendor hops.

3

Expand at your pace

Move additional call flows as confidence grows. Bring your own LLM, STT, or TTS providers, or use the integrated defaults.

4

Consolidate

Replace five invoices with one. Replace five support channels with one. Replace five failure domains with one.

Who gets the 2am ticket? In a five-vendor stack, each provider reports healthy while callers hear silence. The root cause hides in the gap between vendors. In a single stack, one set of logs covers the entire call lifecycle from PSTN to AI and back.

FAQ

Can I bring my own AI providers?

Yes. Use your preferred LLM, STT, or TTS provider alongside the integrated defaults. The platform handles codec conversion, streaming, and orchestration regardless of which providers you choose.

How does pricing work?

AI processing (STT, LLM inference, TTS, and orchestration) at $0.16 per minute. Transport (SIP, PSTN) billed separately at carrier rates. No hidden markup chain from separate providers. No minimum commitment. One invoice covers everything.

What about existing phone numbers?

Port your existing numbers or provision new ones. Global coverage with inbound and outbound, SIP and PSTN native.

Who built this platform?

The team that wrote FreeSWITCH, the open-source telephony engine processing trillions of minutes across the industry. Over 2,000 companies run production workloads on SignalWire.

Trusted by 2,000+ companies

Stop stitching. Start shipping.

One platform from PSTN to AI. One invoice. One set of logs. Built by the FreeSWITCH team.

Get Started Free Read the Docs

One Stack Replaces Your Vendor Chain