# PacketExchange > PacketExchange is the live carrier marketplace for wholesale voice and SMS, connecting carriers, operators and developers on one exchange. Carriers list voice and SMS routes in about two minutes from their own rate sheet and reach buyers worldwide, with every call settled to the seller as it ends. Operators run a hosted Class-4 switch with no hardware, operated in plain English through AI Control, with traffic, margin and settlement in one live view. Developers get one API key and one prepaid balance for SMS, voice calls, the Verify API (one-time codes by SMS or voice call), phone numbers, AI voice agents, least-cost routing and caller ID tests, at the route rate plus a platform fee of 2%, capped at $0.001 per message or call. Key facts: - REST API base URL: https://packetexchange.io/api/v1. JSON over HTTPS. Authenticate with `Authorization: Bearer `. - API keys: live keys (`wmmn_live_sk_...`) send real traffic and charge the balance; test keys (`wmmn_test_sk_...`) simulate against test credit and return `simulated: true`. Keys can be limited to scopes such as `sms:send`, `voice:send`, `verify:write`, `routes:read`, `numbers:write`, `dialer:write` and `billing:write`. - Pricing: the route rate plus 2% (0.5% over your own SIP trunk), capped at $0.001 per message or call. Prepaid: top up from $5 by card or crypto, from $100 by wire, or with USDC on Base over x402 ($5 to $50,000). No contract, no monthly fee. - Money fields are USD decimal strings with exactly 6 places, for example "0.012500". - Errors: `{ "success": false, "error": { "code", "message", "details" } }`. 429 responses carry Retry-After. Send `X-Idempotency-Key` on requests that send, dial or buy. - The SMS send response status is the send-time outcome (accepted, sent or failed). Delivered or failed follows on GET /comms/sms/{id} and the sms.delivered / sms.failed webhooks only when the route returns a carrier receipt; a message that fails on its receipt is refunded. - Route quality on listings: `measured` carries ASR, ACD, NER and median PDD measured by PacketExchange on real buyer calls, once a listing has at least 50 calls from at least two buyers (null before that); expectedAsr, expectedAcd and expectedPdd are the figures the seller states. Seller identities are never exposed. - MCP: https://packetexchange.io/mcp/http (Streamable HTTP, stateless). Send the API key as the connection's `Authorization: Bearer` header; no tool takes a key argument. - Webhooks are signed: `X-PX-Signature: v1=.">`. Reject timestamps more than 5 minutes old. ## Carriers and operators - [List your routes](https://packetexchange.io/list-instantly): Sell voice and SMS termination: upload the rate sheet you already have, destinations and rates are read for you, and you sign in at the end. Free to list; the seller keeps its full rate. - [The Switch and AI Control](https://packetexchange.io/solutions/switch): A hosted Class-4 switch with least-cost routing, failover, A-Z rating, invoicing and netting, run in plain English through AI Control. No hardware. Includes PacketScope SIP packet views and CallGuard call screening. - [Why PacketExchange](https://packetexchange.io/why): How the platform widens margins: no hardware or licences, live settlement, automated operations. - [Marketplace](https://packetexchange.io/marketplace): Every listed route with its rate, caller ID type, capacity and quality. ## Developer docs - [Developer platform](https://packetexchange.io/developers): What the API does, how to start and what it costs. - [API reference](https://packetexchange.io/api-docs): Every endpoint, request, response, error code, scope and rate limit. - [API reference index](https://packetexchange.io/api-docs/reference): Every operation, grouped, each linking to its parameters and schemas. - [OpenAPI specification](https://packetexchange.io/api/v1/docs/json): The OpenAPI 3 document for the whole REST API, as JSON. - [SDKs](https://packetexchange.io/developers/sdks): Node.js and Python SDKs, the OpenAPI spec and the MCP server. - [Example gallery](https://packetexchange.io/developers/examples): Runnable examples for every product in eight languages. - [API changelog](https://packetexchange.io/developers/changelog): Dated changes to the API and what keeps working. - [Documentation](https://packetexchange.io/docs): Guides for the marketplace, the Switch and the API. ## Quickstarts - [Send an SMS](https://packetexchange.io/developers/quickstarts/send-sms): Send a transactional text from a number or an alphanumeric sender, and get its cost back in the response. Endpoints: POST /comms/sms, GET /comms/sms/{messageId}. - [Verify a phone number by SMS](https://packetexchange.io/developers/quickstarts/verify-sms): Text a one-time code and check what the user typed. We generate the code and keep only a hash of it. Endpoints: POST /verify/start, POST /verify/check. - [Verify a phone number by voice call](https://packetexchange.io/developers/quickstarts/verify-voice): Call the user and read a one-time code aloud, digit by digit, in English, Spanish, French, German, Portuguese or Hindi. Endpoints: POST /verify/start, POST /verify/check. - [Make a phone call](https://packetexchange.io/developers/quickstarts/make-a-call): Place an outbound call on a wholesale route and get back its outcome, duration and exact cost when it ends. Endpoints: POST /comms/calls. - [Build an AI voice agent](https://packetexchange.io/developers/quickstarts/ai-voice-agents): Create an agent from a script and rules, rehearse it in a simulated conversation, then attach it to an outbound campaign. Endpoints: POST /ai-agents, POST /ai-agents/{id}/simulate, PUT /dialer/campaigns/{id}. - [Buy a phone number](https://packetexchange.io/developers/quickstarts/buy-a-number): Search the number store by digits, buy a number and point its calls at your SIP server or another phone. Endpoints: GET /dids/search, POST /dids/buy, PATCH /dids/{id}/routing. - [Price a number (least-cost routing)](https://packetexchange.io/developers/quickstarts/price-a-number): See every route that serves a number at the rate it would charge for it, cheapest first, then preview which one Smart Routing would pick. Endpoints: GET /routes/price-number, GET /routes/resolve. - [Test a caller ID on a route](https://packetexchange.io/developers/quickstarts/caller-id-testing): Place a real test call over a route to a handset in the destination country and see which caller ID it displayed. Endpoints: POST /cli-tests, GET /cli-tests/{id}, GET /cli-tests/quota. - [Check routes before you buy](https://packetexchange.io/developers/quickstarts/check-routes): Place one short real call over up to three routes, read a plain verdict for each, then buy the ones that work with your routing order set. Endpoints: POST /routes/check, GET /routes/check/{id}, GET /routes/check/coverage, POST /routes/check/{id}/purchase, POST /routes/check/sms. - [Receive webhooks and verify signatures](https://packetexchange.io/developers/quickstarts/webhooks): Receive sends, completed calls and inbound messages as signed POSTs, and reject anything forged or replayed. Headers: X-PX-Signature, X-PX-Timestamp, X-Webhook-Event, X-Webhook-Id. - [Connect an AI agent over MCP](https://packetexchange.io/developers/quickstarts/mcp): Give Claude, Cursor or your own agent the marketplace as tools: price routes, verify numbers, send and check its balance. Endpoints: POST https://packetexchange.io/mcp/http. ## AI agents - [Build with AI agents](https://packetexchange.io/developers/agents): MCP set-up for Claude Code, Cursor, VS Code, Claude Desktop and Codex, the tool list and x402. - [MCP server](https://packetexchange.io/mcp): The hosted MCP server and every tool with its parameters. - [x402 top-ups](https://packetexchange.io/x402): Fund the balance with USDC on Base over HTTP 402: a balance top-up, not per-request payment. - [Full text for agents](https://packetexchange.io/llms-full.txt): This file plus every quickstart inlined with code and response shapes. ## Pricing - [Developer pricing](https://packetexchange.io/pricing/developers): The fee model and live rates for API traffic. - [Pricing](https://packetexchange.io/pricing): Pricing overview for carriers, the Switch and developers. - [Wholesale pricing](https://packetexchange.io/pricing/wholesale): Pricing for carriers trading on the marketplace. - [Price a number](https://packetexchange.io/developers/quickstarts/price-a-number): Every route for a number at the rate it would charge, cheapest first: GET https://packetexchange.io/api/v1/routes/price-number?number=&type=voice (no key needed). - [Marketplace](https://packetexchange.io/marketplace): Every listed route with its price and caller ID type. ## Products - [SMS messaging](https://packetexchange.io/solutions/sms): Send A2P SMS worldwide on routes bought direct from carriers, at wholesale rates, from one API. - [OTP & verification](https://packetexchange.io/solutions/verification): Send one-time codes by SMS or by a call that reads them aloud, check them with one request, and pay only for the message or call. - [Bulk & marketing SMS](https://packetexchange.io/solutions/marketing): Send promotions, reminders and lifecycle messages in bulk, on operator-direct routes priced from the wholesale market. - [Voice & numbers](https://packetexchange.io/solutions/voice): Outbound termination, inbound numbers and IVR over carrier routes, with the CLI type of every route stated before you buy. - [AI voice agents](https://packetexchange.io/solutions/ai-voice): Write the brief in plain English and the agent calls every number in the campaign: a natural voice, a real conversation and the answers captured as data, over wholesale routes you choose. - [Dialer & outbound](https://packetexchange.io/solutions/dialer): Run voice and SMS campaigns over the carrier routes you choose, with concurrency, calling windows, retries, CLI rotation and DNC suppression under your control. - [Phone numbers](https://packetexchange.io/solutions/numbers): Give your business a local presence in the markets you serve. Buy local, national, mobile and toll-free numbers, point them at your SIP switch or any phone, and take calls in about a minute. - [Wholesale marketplace](https://packetexchange.io/solutions/exchange): Buy voice termination from carriers who list their own routes, compare price and stated quality before you send a call, and pay as you go. Selling? List your routes and reach buyers without chasing bilateral contracts. - [Global connectivity](https://packetexchange.io/solutions/connectivity): Every route comes with its interconnect: a SIP trunk, digest credentials or IP authorisation, and standard codecs, issued with the purchase. - [Switch](https://packetexchange.io/solutions/switch): Bring your suppliers, sign your customers and keep the spread, with least-cost routing, A-Z rating, invoicing and settlement on one account. - [Smart Routing](https://packetexchange.io/solutions/smart-routing): Every call goes down the cheapest route you hold, and in a route group on your Switch it rolls to the next the moment a supplier fails. - [Revenue Turbine](https://packetexchange.io/solutions/route-blending): Revenue Turbine blends several routes into one sellable product: one weighted rate, pooled capacity and a blended quality profile, sold on the marketplace or run on your own switch. - [Caller ID testing](https://packetexchange.io/solutions/caller-id-testing): Real calls to real handsets in the destination country, with the number you presented set beside the number that arrived. - [Route quality & disputes](https://packetexchange.io/solutions/route-quality): Every route shows its ASR, ACD and PDD before you buy, your own calls are measured on each purchase, and when a route slips there is a formal way to raise it and get it fixed. - [Conference introductions](https://packetexchange.io/solutions/introductions): One scan connects two carriers on the exchange, with each other's routes and rates on screen, instead of swapping cards and chasing email for a fortnight. ## Optional - [Platform status](https://packetexchange.io/status): Live health checks of the platform. - [Terms](https://packetexchange.io/terms): Terms of service. - [Privacy](https://packetexchange.io/privacy): Privacy policy. - [Contact](https://packetexchange.io/contact): Sales and support.