Configure chat MCP servers from the dashboard

apps/cluster/migrations/0060_chat_mcp_servers.sql

@@ -0,0 +1,13 @@
+-- The MCP servers chat turns can use, configured on the dashboard (EFF-3443).
+-- No secret is stored here: bearer tokens and OAuth state stay in each
+-- server's credential Durable Object, named by the server's id.
+CREATE TABLE chat_mcp_servers (
+  id TEXT PRIMARY KEY,
+  name TEXT NOT NULL UNIQUE CHECK (name ~ '^[a-z0-9_]{1,32}$'),
+  url TEXT NOT NULL CHECK (url LIKE 'https://%'),
+  auth TEXT NOT NULL CHECK (auth IN ('none', 'bearer', 'oauth')),
+  private BOOLEAN NOT NULL DEFAULT TRUE,
+  enabled BOOLEAN NOT NULL DEFAULT TRUE,
+  created_at TIMESTAMPTZ NOT NULL DEFAULT CLOCK_TIMESTAMP(),
+  updated_at TIMESTAMPTZ NOT NULL DEFAULT CLOCK_TIMESTAMP()
+);

apps/cluster/package.json

@@ -20,6 +20,7 @@
     "@effect/platform-node": "catalog:",
     "@effect/sql-pg": "catalog:",
     "@janitor/domain": "workspace:^",
+    "@modelcontextprotocol/sdk": "catalog:",
     "alchemy": "catalog:",
     "clanka": "catalog:",
     "dfx": "catalog:",

apps/cluster/src/Chat/Agent.ts

@@ -1,6 +1,7 @@
 import * as Agent from "clanka/Agent"
 import type * as AgentExecutor from "clanka/AgentExecutor"
 import type * as AgentOutput from "clanka/AgentOutput"
+import type * as McpServers from "clanka/McpServers"
 import type * as AiError from "effect/ai/AiError"
 import * as LanguageModel from "effect/ai/LanguageModel"
 import * as Model from "effect/ai/Model"
@@ -79,6 +80,8 @@ export interface ChatTurnStart {
   readonly onProgress: (progress: ChatProgress) => Effect.Effect<void>
   /** The `attachFile` tool: succeeds or fails with what the model is told. */
   readonly attachFile: (input: typeof AttachFileParameters.Type) => Effect.Effect<string, string>
+  /** MCP servers the loop and its sub-agents get, connected for the loop's lifetime. */
+  readonly mcp?: Layer.Layer<McpServers.McpServers> | undefined
 }
 
 /** An attached image the model sees with the prompt. */
@@ -239,7 +242,11 @@ const make = Effect.gen(function* () {
         }).pipe(
           Effect.scoped,
           Effect.provide(
-            Layer.merge(options.executor, ChatTools.toLayer({ attachFile: options.attachFile })),
+            Layer.mergeAll(
+              options.executor,
+              ChatTools.toLayer({ attachFile: options.attachFile }),
+              options.mcp ?? Layer.empty,
+            ),
           ),
           Effect.provideContext(model),
           Option.isSome(subagentModel)