import "dotenv/config";
import { z } from "zod";
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { makeOpenAIClient } from "./openai.js";
import { makeChromaClient } from "./chroma.js";
import { toolEmbedText, toolIndexDocuments, toolVectorSearch } from "./tools.js";
const openai = makeOpenAIClient();
const chroma = makeChromaClient();
const embedModel = process.env.OPENAI_EMBED_MODEL || "text-embedding-3-small";
const server = new McpServer({
name: "mcp-tooling-lab",
version: "0.1.0"
});
/**
* embed_text
* Input: { texts: string[] }
* Output: JSON string containing embeddings
*/
server.tool(
"embed_text",
"Generate OpenAI embeddings for an array of texts.",
{
texts: z.array(z.string().min(1)).min(1)
},
async ({ texts }) => {
const out = await toolEmbedText({
openai,
model: embedModel,
texts
});
return {
content: [{ type: "text", text: JSON.stringify(out, null, 2) }]
};
}
);
/**
* index_documents
* Input: { docs: { id: string, text: string, metadata?: object }[] }
* Output: { indexed: number }
*/
server.tool(
"index_documents",
"Embed and index documents into Chroma.",
{
docs: z
.array(
z.object({
id: z.string().min(1),
text: z.string().min(1),
metadata: z.record(z.any()).optional()
})
)
.min(1)
},
async ({ docs }) => {
const out = await toolIndexDocuments({
openai,
model: embedModel,
chroma,
docs
});
return {
content: [{ type: "text", text: JSON.stringify(out, null, 2) }]
};
}
);
/**
* vector_search
* Input: { query: string, topK?: number, where?: object }
* Output: { hits: [...] }
*/
server.tool(
"vector_search",
"Semantic search using embeddings + Chroma. Optional metadata filter via `where`.",
{
query: z.string().min(1),
topK: z.number().int().min(1).max(20).optional(),
where: z.record(z.any()).optional()
},
async ({ query, topK, where }) => {
const out = await toolVectorSearch({
openai,
model: embedModel,
chroma,
query,
topK: topK ?? 5,
where
});
return {
content: [{ type: "text", text: JSON.stringify(out, null, 2) }]
};
}
);
async function main() {
// MCP servers typically run over stdio so hosts (Claude Desktop, etc.) can spawn them.
const transport = new StdioServerTransport();
await server.connect(transport);
}
main().catch((err) => {
console.error("MCP server failed to start:", err);
process.exit(1);
});
