# XDK developer toolkit Build Paxeer X applications in seven languages with native activities, human journeys, agent tools, exchange integrations, and local proof verification. ## Choose your integration plane XDK is the Paxeer X developer toolkit across native activities, payments, Programs, exchange operations, identity, and verifiable settlement. Package and import names retain `layerx`; use the exact language identifiers below in your application. | Plane | Use it for | Entry points | | --- | --- | --- | | Public JSON-RPC | Principal registration, native submission, balances, receipts, proofs, and subscriptions. | `lx_register`, `lx_requestFunds`, `lx_sendActivity` | | Human API | User journeys with a quote, explicit approval, and an idempotent commit. | `move.quote` / `move.commit` | | Agent API | Daemon registration, policy-bound preparation, external signing, submission, and Programs. | `agent.register`, `prepare`, `submit`, `program.*` | | MCP | Tool calls from assistants through the same agent daemon gates. | [21 scoped tools](https://docs.paxeer.app/mcp) | | Offline verification | Independent receipt, outcome, terminal, and transfer-root checks. | Language-specific local verifiers | ## Seven language SDKs | Language | Package | Payment entry point | Receipt verifier | | --- | --- | --- | --- | | Rust | `layerx-sdk` | `RpcClient::send_activity` | `production::verify_receipt` | | TypeScript | `@sidiora/layerx-sdk` | `JsonRpcClient.sendActivity`; `ProductionClient.human` | `verifyReceipt` | | Python | `layerx-sdk` | `PaymentRpc.send`; `ProductionClient.human` | `verify_receipt` | | Go | `github.com/Sidiora-Labs/LayerX-Network/platform/sdk/go` | `Client.Human` | `VerifyReceipt` | | JVM | `com.sidiora.layerx:layerx-sdk` | `ProductionClient.human` | `LocalVerifier.verifyReceipt` | | Swift | `LayerXSDK` | `humanMoveQuote` / `humanMoveCommit` | `LocalVerifier.verifyReceipt` | | .NET | `LayerX.Sdk` | `HumanMoveQuoteAsync` / `HumanMoveCommitAsync` | `LocalVerifier.VerifyReceiptAsync` | ## Native and application API families | Family | Developer surface | | --- | --- | | Native activities | Canonical encoders, intent construction, account derivation, fee estimation, sequencing, and signed activity submission. | | Programs | Program lifecycle, native program calls, transfer authority, call graphs, runtime terminals, and occupancy settlement. | | Spot and perpetuals | `buildSpotActivity`, `decodeSpotActivity`, `buildPerpsActivity`, and `decodePerpsActivity` construct and inspect native trading payloads. | | Exchange | ABI helpers construct order placement, cancellation, settlement, and margin transactions; event decoders inspect exchange logs. | | Bridge | `bridgeInCall`, `bridgeOutCall`, and `decodeBridgeEvent` bind cross-network transfer requests to the bridge ABI. | | Launchpad | Market creation, buy and sell calls, fee strategies, fee claims, airdrops, burns, LP rewards, and pause controls. | | Streams and mirrors | Bounded pages, stable cursors, subscriptions, and local mirrors support replayable application views. | | XWeb and agent services | XWeb API, web search, native capabilities, gas-station support, and policy-aware transport interfaces. | ## Credentials, amounts, and retries Use Bearer identity sessions for authenticated human journeys and faucet claims. Public activity submission uses a `LayerX-Key` credential with `activity:write`. These credentials authorize different operations. Keep secret material in `SecretBytes` or the language credential wrapper, and keep signing outside application logs. Use protocol integer amounts or decimal strings rather than floating point values. Attach a stable idempotency key to a business action and preserve it across retries. A submission result can be pending; poll or subscribe until the requested commitment is reached, then verify the receipt. ## Transport selection The generated operation catalog defines names and schemas; the transport determines the reachable plane. TypeScript, Python, and Swift agent HTTP transports route Programs operations. Go provides a human HTTP transport. JVM transport accepts separate human and agent origins. Supply an agent-capable transport for daemon operations and use public JSON-RPC for self-service principal registration. Start with [SDK quickstarts](https://docs.paxeer.app/sdk-quickstarts), then continue to [MCP tools](https://docs.paxeer.app/mcp), [Programs](https://docs.paxeer.app/programs), and [public JSON-RPC](https://docs.paxeer.app/public-rpc).