v3.9.0 — Phase 5 Part 7: MCP Networking

[Jovancoding]

v3.9.0 — Phase 5 Part 7: MCP Networking

## Phase 5 Part 7: MCP Networking

Exposes any blackboard as a JSON-RPC 2.0 Model Context Protocol endpoint,
enabling cross-machine agent communication with zero external dependencies.

### Architecture

McpBridgeClient ──► McpTransport ──► McpBlackboardBridge
listTools() (in-process, handleRPC()
callTool() SSE, WS, ├─ tools/list
sendRaw() stdio, ...) └─ tools/call
│
BlackboardMCPTools
(read/write/list/
delete/exists)

### New: `McpBlackboardBridge`

```typescript
import { McpBlackboardBridge, McpBridgeClient, McpInProcessTransport } from 'network-ai';

// Server side — wrap any blackboard
const bridge = new McpBlackboardBridge(myBlackboard, { name: 'prod' });

// Client side — in-process (swap for SSE/WS transport without changing this code)
const client = new McpBridgeClient(new McpInProcessTransport(bridge));

const tools  = await client.listTools();          // all 5 blackboard tools
const result = await client.callTool('blackboard_write', {
  key: 'deploy:status', value: '"stable"', agent_id: 'ci',
});

New: McpBridgeRouter — multi-board routing

import { McpBridgeRouter, McpBlackboardBridge } from 'network-ai';

const router = new McpBridgeRouter();
router.register('prod',    new McpBlackboardBridge(prodBoard));
router.register('staging', new McpBlackboardBridge(stagingBoard));

const prodClient    = router.getClient('prod');
const stagingClient = router.getClient('staging');

// Boards are fully isolated — writes to prod don't appear in staging
await prodClient.callTool('blackboard_write',  { key: 'ver', value: '"1.0"', agent_id: 'ci' });
await stagingClient.callTool('blackboard_write', { key: 'ver', value: '"1.1-rc"', agent_id: 'ci' });

New: McpTransport interface — swap transports without changing callers

import type { McpTransport } from 'network-ai';

// Custom transport example (recording/logging wrapper)
const recordingTransport: McpTransport = {
  async send(req) {
    console.log('→', req.method, req.id);
    const res = await bridge.handleRPC(req);
    console.log('←', res.id, res.error ? 'ERR' : 'OK');
    return res;
  },
};

const client = new McpBridgeClient(recordingTransport);

Features

• Full JSON-RPC 2.0 — standard error codes: -32700 / -32600 / -32601 / -32602 / -32603
• McpCallToolResult — follows MCP CallToolResult shape; isError flag for error detection without parsing content
• Zero external dependencies — in-process transport works with no network stack
• Transport-agnostic — implement McpTransport to add SSE, WebSocket, or stdio delivery
• Works with all Phase 5 backends — pair with CrdtBackend or RedisBackend for distributed blackboard access over MCP

Exports

import {
  McpBlackboardBridge,
  McpBridgeClient,
  McpBridgeRouter,
  McpInProcessTransport,
  type McpJsonRpcRequest,
  type McpJsonRpcResponse,
  type McpTransport,
  type McpListToolsResult,
  type McpCallToolResult,
  type McpBlackboardBridgeOptions,
} from 'network-ai';

Stats

• 121 new tests in test-phase5g.ts
• 1095 tests passing (0 failing)
• No breaking changes

---

Phase 5 complete — all 7 parts shipped.

Version	Part	Feature
v3.4.0	1	Named Multi-Blackboard API
v3.5.0	2	Pluggable Backend API
v3.6.0	3	Redis Backend
v3.7.0	4	CRDT Vector-Clock Backend
v3.7.1	5	Configurable Consistency Levels
v3.8.0	6	Federated Budget Tracking
v3.9.0	7	MCP Networking

Full changelog: https://github.com/jovanSAPFIONEER/Network-AI/blob/main/CHANGELOG.md#390---2026-02-25

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This discussion was created from the release v3.9.0 — Phase 5 Part 7: MCP Networking.