fix(agent): add error handling and plugin tools (#53)

* fix(agent): add error handling and plugin tools

Replace useless try/catch with streaming-aware error
callbacks. streamText is lazy so errors occur during
streaming, not at call time. Now unwraps RetryError
to extract the actual APICallError with status code
and response body from OpenRouter.

Also adds API key validation, model ID fallback, and
includes plugin tools in the streamText call.

* chore(db): fix file permissions on 0015 snapshot

---------

Co-authored-by: Nicholai <nicholaivogelfilms@gmail.com>

src/app/api/agent/route.ts

@@ -2,12 +2,15 @@ import {
   streamText,
   stepCountIs,
   convertToModelMessages,
+  RetryError,
   type UIMessage,
 } from "ai"
+import { APICallError } from "@ai-sdk/provider"
 import { getCloudflareContext } from "@opennextjs/cloudflare"
 import {
   resolveModelForUser,
   createModelFromId,
+  DEFAULT_MODEL_ID,
 } from "@/lib/agent/provider"
 import { agentTools } from "@/lib/agent/tools"
 import { githubTools } from "@/lib/agent/github-tools"
@@ -28,14 +31,28 @@ export async function POST(req: Request): Promise<Response> {
   const db = getDb(env.DB)
   const envRecord = env as unknown as Record<string, string>
 
+  const apiKey = envRecord.OPENROUTER_API_KEY
+  if (!apiKey) {
+    return new Response(
+      JSON.stringify({
+        error: "OPENROUTER_API_KEY not configured",
+      }),
+      {
+        status: 500,
+        headers: { "Content-Type": "application/json" },
+      }
+    )
+  }
+
   const [memories, registry] = await Promise.all([
     loadMemoriesForPrompt(db, user.id),
     getRegistry(db, envRecord),
   ])
 
   const pluginSections = registry.getPromptSections()
+  const pluginTools = registry.getTools()
 
-  const body = await req.json() as {
+  const body = (await req.json()) as {
     messages: UIMessage[]
   }
 
@@ -47,14 +64,16 @@ export async function POST(req: Request): Promise<Response> {
     req.headers.get("x-conversation-id") ||
     crypto.randomUUID()
 
-  const modelId = await resolveModelForUser(
-    db,
-    user.id
-  )
-  const model = createModelFromId(
-    envRecord.OPENROUTER_API_KEY,
-    modelId
-  )
+  let modelId = await resolveModelForUser(db, user.id)
+  if (!modelId || !modelId.includes("/")) {
+    console.error(
+      `Invalid model ID resolved: "${modelId}",` +
+        ` falling back to default`
+    )
+    modelId = DEFAULT_MODEL_ID
+  }
+
+  const model = createModelFromId(apiKey, modelId)
 
   const result = streamText({
     model,
@@ -67,9 +86,34 @@ export async function POST(req: Request): Promise<Response> {
       pluginSections,
       mode: "full",
     }),
-    messages: await convertToModelMessages(body.messages),
-    tools: { ...agentTools, ...githubTools },
+    messages: await convertToModelMessages(
+      body.messages
+    ),
+    tools: {
+      ...agentTools,
+      ...githubTools,
+      ...pluginTools,
+    },
     stopWhen: stepCountIs(10),
+    onError({ error }) {
+      const apiErr = unwrapAPICallError(error)
+      if (apiErr) {
+        console.error(
+          `Agent API error [model=${modelId}]`,
+          `status=${apiErr.statusCode}`,
+          `body=${apiErr.responseBody}`
+        )
+      } else {
+        const msg =
+          error instanceof Error
+            ? error.message
+            : String(error)
+        console.error(
+          `Agent error [model=${modelId}]:`,
+          msg
+        )
+      }
+    },
   })
 
   ctx.waitUntil(
@@ -82,5 +126,29 @@ export async function POST(req: Request): Promise<Response> {
     )
   )
 
-  return result.toUIMessageStreamResponse()
+  return result.toUIMessageStreamResponse({
+    onError(error) {
+      const apiErr = unwrapAPICallError(error)
+      if (apiErr) {
+        return (
+          apiErr.responseBody ??
+          `Provider error (${apiErr.statusCode})`
+        )
+      }
+      return error instanceof Error
+        ? error.message
+        : "Unknown error"
+    },
+  })
+}
+
+function unwrapAPICallError(
+  error: unknown
+): APICallError | undefined {
+  if (APICallError.isInstance(error)) return error
+  if (RetryError.isInstance(error)) {
+    const last: unknown = error.lastError
+    if (APICallError.isInstance(last)) return last
+  }
+  return undefined
 }