greentic-mcp-client

Client for remote MCP servers over Streamable HTTP (JSON-RPC 2.0, protocol 2025-06-18).

Not to be confused with greentic-mcp (greentic-mcp-exec), which loads and executes wasix:mcp WASM components locally. This crate is the network-client side.

Layout

• proto — sans-io protocol core: request builders, SSE-aware response parsing, tool mapping. Compiles for wasm32-wasip2 (default-features = false).
• client — McpHttpClient (feature native, default): reqwest transport, Mcp-Session-Id threading, configurable auth header.

Usage (native)

use greentic_mcp_client::{McpAuth, McpClientOptions, McpHttpClient};
use url::Url;

let mut client = McpHttpClient::new(
    Url::parse("https://example.com/mcp")?,
    Some(McpAuth::bearer("token")),
    McpClientOptions::default(),
)?;
let info = client.initialize().await?;
let tools = client.list_tools().await?;
let out = client.call_tool("echo", &serde_json::json!({ "msg": "hi" })).await?;

Usage (wasm extension)

greentic-mcp-client = { version = "0.1", default-features = false }

Use the proto builders/parsers with your host's HTTP imports.

Consumers

• greentic-designer-admin — tenant MCP-server test-connection endpoint
• greentic-designer — flow-prompt MCP tool source (planned)
• greentic-aw-runtime — agentic-worker MCP tool dispatch (planned)
• component-github-mcp-ext — proto layer inside the WASM extension (planned refactor)