Managed agents endpoints addition

netlify/functions/agent-proxy.js

@@ -3,19 +3,29 @@ import Anthropic from '@anthropic-ai/sdk'
 /**
  * Netlify Functions v2 handler.
  *
- * Proxies a request from the React frontend to the Anthropic Messages API,
- * configured for a Managed Agent workflow. We pipe `content_block_delta`
- * events directly to the client through a ReadableStream so we never hit
- * Netlify's 26-second synchronous execution limit.
+ * Proxies a request from the React frontend to a Claude Console-defined
+ * Managed Agent via the /v1/sessions endpoints. The agent's model, system
+ * prompt, tools, MCP servers, and skills are configured in the Console and
+ * referenced here by ID. We open the SSE event stream first, then send a
+ * `user.message` event, and pipe each `agent.message` text block to the
+ * client through a ReadableStream so we never hit Netlify's 26-second
+ * synchronous execution limit.
  */
 
 // ---------------------------------------------------------------------------
 // Managed Agent configuration
 // ---------------------------------------------------------------------------
-// The Managed Agent ID is supplied via the ANTHROPIC_AGENT_ID env var. The
-// agent's system prompt and model are defined in the Claude Console and used
-// by default. ANTHROPIC_MODEL and ANTHROPIC_SYSTEM_PROMPT may optionally
-// override them.
+// The Managed Agent ID and Environment ID come from the Claude Console.
+// Optionally, vault IDs may be passed for MCP credential access.
+const AGENT_ID = process.env.ANTHROPIC_AGENT_ID
+const ENVIRONMENT_ID = process.env.ANTHROPIC_ENVIRONMENT_ID
+const VAULT_IDS = (process.env.ANTHROPIC_VAULT_IDS || '')
+  .split(',')
+  .map((s) => s.trim())
+  .filter(Boolean)
+
+// All Managed Agents endpoints require this beta header.
+const MANAGED_AGENTS_BETA = 'managed-agents-2026-04-01'
 
 // ---------------------------------------------------------------------------
 // Anthropic client (reused across warm Lambda invocations)
@@ -28,6 +38,7 @@ function getClient() {
   }
   _client = new Anthropic({
     apiKey: process.env.ANTHROPIC_API_KEY,
+    defaultHeaders: { 'anthropic-beta': MANAGED_AGENTS_BETA },
   })
   return _client
 }
@@ -60,6 +71,13 @@ export default async (req /*, context */) => {
     return new Response('Invalid station website URL', { status: 400 })
   }
 
+  if (!AGENT_ID || !ENVIRONMENT_ID) {
+    return new Response(
+      'Server is missing ANTHROPIC_AGENT_ID or ANTHROPIC_ENVIRONMENT_ID',
+      { status: 500 },
+    )
+  }
+
   let client
   try {
     client = getClient()
@@ -78,54 +96,83 @@ export default async (req /*, context */) => {
 
 Please follow your instructions to produce the funding outlook brief.`
 
-  // ----- Build the streaming request -----
-  // The Managed Agent's system prompt and model (configured in the Claude
-  // Console) are used by default. Optional env vars can override them.
-  const streamArgs = {
-    model: process.env.ANTHROPIC_MODEL || 'claude-opus-4-6',
-    max_tokens: 20000,
-    messages: [
-      {
-        role: 'user',
-        content: [{ type: 'text', text: userMessage }],
-      },
-    ],
-  }
-  if (process.env.ANTHROPIC_AGENT_ID) {
-    streamArgs.agent_id = process.env.ANTHROPIC_AGENT_ID
-  }
-  if (process.env.ANTHROPIC_SYSTEM_PROMPT) {
-    streamArgs.system = process.env.ANTHROPIC_SYSTEM_PROMPT
+  // ----- Create the session -----
+  let session
+  try {
+    const sessionParams = {
+      agent: AGENT_ID,
+      environment_id: ENVIRONMENT_ID,
+    }
+    if (VAULT_IDS.length) sessionParams.vault_ids = VAULT_IDS
+    session = await client.beta.sessions.create(sessionParams)
+  } catch (err) {
+    return new Response(
+      `Failed to create session: ${err.message || err}`,
+      { status: 500 },
+    )
   }
 
-  const upstream = client.messages.stream(streamArgs)
+  // ----- Open the event stream BEFORE sending the user message -----
+  // (Stream-first ensures we don't miss any events the agent emits.)
+  let upstream
+  try {
+    upstream = await client.beta.sessions.events.stream(session.id)
+  } catch (err) {
+    return new Response(
+      `Failed to open session event stream: ${err.message || err}`,
+      { status: 500 },
+    )
+  }
 
-  // ----- Pipe content_block_delta events straight to the client -----
+  // ----- Send the kickoff user.message event -----
+  try {
+    await client.beta.sessions.events.send(session.id, {
+      events: [
+        {
+          type: 'user.message',
+          content: [{ type: 'text', text: userMessage }],
+        },
+      ],
+    })
+  } catch (err) {
+    return new Response(
+      `Failed to send user message: ${err.message || err}`,
+      { status: 500 },
+    )
+  }
+
+  // ----- Pipe agent.message text blocks to the client -----
   const encoder = new TextEncoder()
+  const seenEventIds = new Set()
   const stream = new ReadableStream({
     async start(controller) {
       try {
         for await (const event of upstream) {
-          if (
-            event.type === 'content_block_delta' &&
-            event.delta?.type === 'text_delta' &&
-            event.delta.text
-          ) {
-            controller.enqueue(encoder.encode(event.delta.text))
+          if (event.id) {
+            if (seenEventIds.has(event.id)) {
+              // Still need to evaluate terminal events even if seen.
+            } else {
+              seenEventIds.add(event.id)
+              if (event.type === 'agent.message' && Array.isArray(event.content)) {
+                for (const block of event.content) {
+                  if (block?.type === 'text' && block.text) {
+                    controller.enqueue(encoder.encode(block.text))
+                  }
+                }
+              } else if (event.type === 'session.error') {
+                const msg = event.error?.message || 'unknown session error'
+                controller.enqueue(encoder.encode(`\n\n[session error: ${msg}]`))
+              }
+            }
           }
 
-          // Surface an explicit message if the agent decides to call a tool.
-          // (Managed Agents may emit `input_json_delta` or `tool_use` blocks.)
+          // Terminal-state gate.
+          if (event.type === 'session.status_terminated') break
           if (
-            event.type === 'content_block_delta' &&
-            event.delta?.type === 'input_json_delta' &&
-            event.delta.partial_json
+            event.type === 'session.status_idle' &&
+            event.stop_reason?.type !== 'requires_action'
           ) {
-            controller.enqueue(
-              encoder.encode(
-                `\n\n_[agent requested tool input: ${event.delta.partial_json}]_\n\n`,
-              ),
-            )
+            break
           }
         }
         controller.close()
@@ -137,8 +184,12 @@ Please follow your instructions to produce the funding outlook brief.`
       }
     },
     cancel() {
-      // If the client disconnects, abort the upstream Anthropic request.
-      upstream.controller?.abort?.()
+      // If the client disconnects, abort the upstream stream.
+      try {
+        upstream.controller?.abort?.()
+      } catch {
+        /* ignore */
+      }
     },
   })