SDK overview

An SDK is the part of Tesseron that lives in your process. It serialises outgoing JSON-RPC, dispatches incoming method calls into your handlers, and wraps the per-invocation protocol glue (progress, cancel, sample, elicit) in a shape that feels natural in the host language.

Today we ship five TypeScript packages. The surface they expose - the SDK contract - is the portable part. A Python or Go implementation reuses the same concepts.

The shipped TypeScript SDK

flowchart LR
core["@tesseron/core<br/>action & resource builders<br/>JSON-RPC dispatcher<br/>protocol types"]
web["@tesseron/web<br/>browser client<br/>WebSocket transport"]
server["@tesseron/server<br/>Node client<br/>ws transport"]
react["@tesseron/react<br/>useTesseronAction<br/>useTesseronResource<br/>useTesseronConnection"]
mcp["@tesseron/mcp<br/>MCP gateway<br/>MCP stdio bridge"]
web -- "re-exports" --> core
server -- "re-exports" --> core
react -- "wraps" --> web
mcp -. "shared types" .-> core

Five packages. core owns the protocol types and builder; the others wrap transport and framework integration.

Quickstart Install one package, declare one action, connect.

@tesseron/core Action & resource builders, JSON-RPC dispatcher, protocol types. Zero runtime deps beyond Standard Schema.

@tesseron/web Browser WebSocket transport + singleton client.

@tesseron/server Node `ws`-backed transport + singleton client.

@tesseron/react `useTesseronAction`, `useTesseronResource`, `useTesseronConnection`.

@tesseron/mcp The MCP gateway itself. CLI, bundled into the Claude Code plugin.

The portable SDK contract

Whatever language you implement Tesseron in, the SDK has to expose these primitives. They correspond 1:1 with the protocol.

Primitive	In TypeScript	Covers
Client lifecycle	`tesseron.app({ id, name, … })` + `tesseron.connect()`	Handshake, session ID, claim code.
Action builder	`.action(name).describe(…).input(…).output(…).handler(fn)`	Declaring a named, typed, handler-backed action.
Resource builder	`.resource(name).read(fn).subscribe(emitter)`	Declaring readable + optionally subscribable state.
Standard Schema bridge	Accepts any `StandardSchemaV1<T>` validator (Zod, Valibot, ArkType, …)	Input / output / sampling / elicitation validation.
Invocation context	`(input, ctx)` passed to every handler	`ctx.signal`, `ctx.progress`, `ctx.sample`, `ctx.confirm`, `ctx.elicit`, `ctx.log`, `ctx.agent`, `ctx.agentCapabilities`, `ctx.client`.
Transport abstraction	`Transport { send, onMessage, onClose, close }`	WebSocket in practice, but the protocol is transport-agnostic.
JSON-RPC dispatcher	`JsonRpcDispatcher`	Request/notification handling, ID correlation, timeout, error mapping.
Structured error model	`TesseronError(code, message, data?)`	Mapping to / from JSON-RPC error objects with the error codes in the catalog.

Other SDKs

Python SDK (planned) Status, intended shape, timeline.

Port Tesseron to your language Step-by-step guide, protocol conformance checklist, test strategy.