refactor(cli): scope server discovery to CLI

packages/core/src/flag/flag.ts

@@ -38,6 +38,7 @@ export const Flag = {
   ),
   OPENCODE_EXPERIMENTAL_DISABLE_COPY_ON_SELECT:
     copy === undefined ? process.platform === "win32" : truthy("OPENCODE_EXPERIMENTAL_DISABLE_COPY_ON_SELECT"),
+  OPENCODE_EXPERIMENTAL_MINIMAL_THINKING: truthy("OPENCODE_EXPERIMENTAL_MINIMAL_THINKING"),
   OPENCODE_MODELS_URL: process.env["OPENCODE_MODELS_URL"],
   OPENCODE_MODELS_PATH: process.env["OPENCODE_MODELS_PATH"],
   OPENCODE_DB: process.env["OPENCODE_DB"],

packages/opencode/specs/effect/errors.md

@@ -70,54 +70,11 @@ Endpoint definitions declare which public errors can be emitted. Public
 HTTP error schemas carry their response status with `httpApiStatus` or the
 equivalent HttpApi schema annotation.
 
-Effect's own HttpApi examples follow this pattern:
-
-```ts
-export class Unauthorized extends Schema.TaggedErrorClass<Unauthorized>()(
-  "Unauthorized",
-  { message: Schema.String },
-  { httpApiStatus: 401 },
-) {}
-
-export class Authorization extends HttpApiMiddleware.Service<
-  Authorization,
-  {
-    provides: CurrentUser
-  }
->()("app/Authorization", {
-  security: { bearer: HttpApiSecurity.bearer },
-  error: Unauthorized,
-}) {}
-```
-
-Endpoint-level errors use the same idea:
-
-```ts
-export class ConfigApiError extends Schema.ErrorClass<ConfigApiError>("ConfigApiError")(
-  {
-    name: Schema.Union(Schema.Literal("ConfigInvalidError"), Schema.Literal("ConfigJsonError")),
-    data: Schema.Struct({ message: Schema.optional(Schema.String), path: Schema.String }),
-  },
-  { httpApiStatus: 400 },
-) {}
-
-HttpApiEndpoint.get("get", "/config", {
-  success: Config.Info,
-  error: ConfigApiError,
-})
-```
-
 The service error and HTTP error may be the same class only when the wire
 shape is intentionally public. Use separate HTTP error schemas when the
 service error contains internals, low-level causes, retry hints, or data
 that should not be exposed to API clients.
 
-Do not map every domain error into one universal HTTP error class. Prefer a
-small public error vocabulary by route group: shared shapes like
-`ApiNotFoundError`, route-specific shapes like `ConfigApiError`, and built-in
-empty `HttpApiError.*` only when an empty/no-content body is the intended SDK
-contract.
-
 ## Mapping Guidance
 
 - Keep one-off translations inline in the handler.
@@ -129,35 +86,6 @@ contract.
   breaking API change.
 - Use built-in `HttpApiError.*` only when its generated body and SDK
   surface are intentionally the public contract.
-- Prefer `Schema.ErrorClass` for public HTTP error bodies whose wire shape is
-  not the same as the internal domain error shape.
-- Prefer `Schema.TaggedErrorClass` for service/domain errors and middleware
-  errors that are naturally tagged by `_tag`.
-- If preserving a legacy `{ name, data }` body, model that shape explicitly in
-  the public API error schema instead of relying on `NamedError.toObject()` in
-  generic middleware.
-
-## User-Facing Rendering
-
-HTTP serialization and user rendering are separate boundaries. The server
-should send structured public errors; CLI and TUI code should format those
-structures through one shared formatter.
-
-For SDK calls using `{ throwOnError: true }`, the generated client may wrap the
-decoded response body in an `Error`. The original body should remain available
-under `error.cause.body`; `FormatError` is the right place to unwrap and render
-that body. TUI aggregation helpers should call `FormatError` first, then fall
-back to generic `Error.message` / string rendering.
-
-When several parallel startup requests fail from the same underlying issue,
-group identical rendered messages and list the affected request names once.
-For example:
-
-```text
-Configuration is invalid at /path/to/opencode.json
-↳ Expected object, got "not-object" provider.bad.options
-Affected startup requests: config.providers, provider.list, app.agents, config.get
-```
 
 ## Middleware Guidance
 
@@ -171,15 +99,6 @@ middleware should shrink. It should not gain new name checks.
 Unknown `500` responses should log full details server-side with
 `Cause.pretty(cause)` and return a safe public body.
 
-The config startup regression in #27056 is the failure mode this rule is meant
-to avoid: a user-authored invalid `opencode.json` crossed the HttpApi boundary
-as a defect, so middleware replaced a useful `ConfigInvalidError` with a safe
-generic `UnknownError`. The compatibility fix is to preserve config parse and
-validation errors as client-visible `400`s. The target architecture is better:
-config loading should fail on the typed error channel, config HTTP handlers
-should map those errors to declared `ConfigApiError` responses, and the generic
-middleware should never see them.
-
 ## Migration Order
 
 Prefer small vertical slices:
@@ -194,9 +113,6 @@ Prefer small vertical slices:
 Good early domains are storage not-found, worktree errors, and provider
 auth validation errors because they currently drive HTTP behavior.
 
-Config parse and validation errors are also a good early slice because they
-are startup-blocking and must be rendered clearly in both CLI and TUI flows.
-
 ## Checklist For A PR
 
 - [ ] Expected failures are typed errors, not defects.

packages/opencode/src/cli/cmd/serve.ts

@@ -1,24 +1,42 @@
 import { Effect } from "effect"
 import { Server } from "../../server/server"
+import { ServerDiscovery } from "@/cli/server-discovery"
 import { effectCmd } from "../effect-cmd"
 import { withNetworkOptions, resolveNetworkOptions } from "../network"
 import { Flag } from "@opencode-ai/core/flag/flag"
 
 export const ServeCommand = effectCmd({
   command: "serve",
-  builder: (yargs) => withNetworkOptions(yargs),
+  builder: (yargs) =>
+    withNetworkOptions(yargs).option("discoverable", {
+      type: "boolean",
+      describe: "write this server to the local discovery file for default TUI startup",
+      default: false,
+    }),
   describe: "starts a headless opencode server",
   // Server loads instances per-request via x-opencode-directory header — no
   // need for an ambient project InstanceContext at startup.
   instance: false,
-  handler: Effect.fn("Cli.serve")(function* (args) {
-    if (!Flag.OPENCODE_SERVER_PASSWORD) {
-      console.log("Warning: OPENCODE_SERVER_PASSWORD is not set; server is unsecured.")
-    }
-    const opts = yield* resolveNetworkOptions(args)
-    const server = yield* Effect.promise(() => Server.listen(opts))
-    console.log(`opencode server listening on http://${server.hostname}:${server.port}`)
+  handler: (args) =>
+    Effect.gen(function* () {
+      if (!Flag.OPENCODE_SERVER_PASSWORD) {
+        console.log("Warning: OPENCODE_SERVER_PASSWORD is not set; server is unsecured.")
+      }
+      const opts = yield* resolveNetworkOptions(args)
+      const server = yield* Effect.promise(() => Server.listen(opts))
+      const discovery = args.discoverable ? yield* ServerDiscovery.Service : undefined
+      if (discovery) {
+        yield* discovery.write(server.url)
+        process.on("exit", ServerDiscovery.removeSync)
+      }
+      console.log(`opencode server listening on http://${server.hostname}:${server.port}`)
 
-    yield* Effect.never
-  }),
+      yield* Effect.never.pipe(
+        Effect.ensuring(
+          discovery
+            ? discovery.remove().pipe(Effect.ensuring(Effect.sync(() => process.off("exit", ServerDiscovery.removeSync))))
+            : Effect.void,
+        ),
+      )
+    }).pipe(Effect.provide(ServerDiscovery.defaultLayer)),
 })

packages/opencode/src/cli/cmd/tui/context/aggregate-failures.ts

@@ -1,5 +1,3 @@
-import { FormatError } from "@/cli/error"
-
 /**
  * Aggregate Promise.allSettled results into a single Error that names every
  * failed endpoint, or return null when all fulfilled. Used at TUI bootstrap
@@ -17,19 +15,7 @@ export function aggregateFailures(labeled: LabeledSettled[]): Error | null {
   )
   if (failed.length === 0) return null
 
-  const reasons = Array.from(
-    failed
-      .map((f) => ({ name: f.name, message: reasonMessage(f.result.reason) }))
-      .reduce((grouped, failure) => {
-        grouped.set(failure.message, [...(grouped.get(failure.message) ?? []), failure.name])
-        return grouped
-      }, new Map<string, string[]>())
-      .entries(),
-  )
-    .map(([message, names]) =>
-      names.length === 1 ? `${names[0]}: ${message}` : `${message}\nAffected startup requests: ${names.join(", ")}`,
-    )
-    .join("; ")
+  const reasons = failed.map((f) => `${f.name}: ${reasonMessage(f.result.reason)}`).join("; ")
   const summary = `${failed.length} of ${labeled.length} requests failed: ${reasons}`
   const err = new Error(summary)
   err.cause = { failures: failed.map((f) => ({ name: f.name, reason: f.result.reason })) }
@@ -37,9 +23,6 @@ export function aggregateFailures(labeled: LabeledSettled[]): Error | null {
 }
 
 function reasonMessage(reason: unknown): string {
-  const formatted = FormatError(reason)
-  if (formatted) return formatted
-
   if (reason instanceof Error) return reason.message
   if (typeof reason === "string") return reason
   if (reason && typeof reason === "object") {

packages/opencode/src/cli/cmd/tui/context/thinking.ts

@@ -1,9 +1,10 @@
 import { createMemo, type Setter } from "solid-js"
+import { Flag } from "@opencode-ai/core/flag/flag"
 import { useKV } from "./kv"
 
-export type ThinkingMode = "show" | "hide"
+export type ThinkingMode = "show" | "minimal" | "hide"
 
-const MODES: readonly ThinkingMode[] = ["show", "hide"] as const
+const MODES: readonly ThinkingMode[] = ["show", "minimal", "hide"] as const
 
 // OpenAI's Responses API surfaces reasoning summaries that start with a bolded
 // title line: "**Inspecting PR workflow**\n\n<body>". GitHub Copilot routes
@@ -19,7 +20,7 @@ export function isThinkingMode(value: unknown): value is ThinkingMode {
   return typeof value === "string" && (MODES as readonly string[]).includes(value)
 }
 
-// Cycle order matches the slash command: show → hide → show.
+// Cycle order matches the slash command: show → minimal → hide → show.
 export function nextThinkingMode(current: ThinkingMode): ThinkingMode {
   const idx = MODES.indexOf(current)
   return MODES[(idx + 1) % MODES.length] ?? "show"
@@ -32,7 +33,7 @@ export function useThinkingMode() {
   // The KVProvider only renders children once kv.ready, so reads here are safe.
   const hadStored = kv.get("thinking_mode") !== undefined
   const legacy = kv.get("thinking_visibility")
-  const [stored, setStored] = kv.signal<ThinkingMode>("thinking_mode", "hide")
+  const [stored, setStored] = kv.signal<ThinkingMode>("thinking_mode", "minimal")
 
   // The kv signal exposes its setter typed as `Setter<T>` which carries Solid's
   // overload set; passing an updater fn through a property access loses the
@@ -46,21 +47,21 @@ export function useThinkingMode() {
 
   // Preserve previous experience for users who had explicitly toggled the
   // legacy `thinking_visibility` boolean. First-time users (no legacy key)
-  // get the new "hide" default (collapsed thinking).
+  // get the new "minimal" default.
   if (!hadStored) {
     if (legacy === true) set("show")
     else if (legacy === false) set("hide")
   }
 
-  if ((stored() as string) === "minimal") set("hide")
-
   const mode = createMemo<ThinkingMode>(() => {
+    if (Flag.OPENCODE_EXPERIMENTAL_MINIMAL_THINKING) return "minimal"
     const value = stored()
-    return isThinkingMode(value) ? value : "hide"
+    return isThinkingMode(value) ? value : "minimal"
   })
 
   return {
     mode,
     set,
+    locked: () => Flag.OPENCODE_EXPERIMENTAL_MINIMAL_THINKING === true,
   }
 }

packages/opencode/src/cli/cmd/tui/feature-plugins/system/session-v2.tsx

@@ -392,7 +392,7 @@ function AssistantReasoning(props: {
   const thinking = useThinkingMode()
   const [expanded, setExpanded] = createSignal(false)
   const content = createMemo(() => props.part.text.replace("[REDACTED]", "").trim())
-  const inMinimal = createMemo(() => thinking.mode() === "hide")
+  const inMinimal = createMemo(() => thinking.mode() === "minimal")
   // v2 reasoning parts have no per-part `time.end` (see SessionMessageAssistantReasoning
   // in the v2 SDK); we settle on parent-message completion instead.
   const isDone = createMemo(() => props.completedAt() !== undefined)
@@ -404,7 +404,7 @@ function AssistantReasoning(props: {
   }
 
   return (
-    <Show when={content()}>
+    <Show when={content() && thinking.mode() !== "hide"}>
       <Switch>
         <Match when={!inMinimal() || expanded()}>
           <box

packages/opencode/src/cli/cmd/tui/routes/session/index.tsx

@@ -218,7 +218,7 @@ export function Session() {
   const [conceal, setConceal] = createSignal(true)
   const thinking = useThinkingMode()
   const thinkingMode = thinking.mode
-  const showThinking = createMemo(() => true)
+  const showThinking = createMemo(() => thinkingMode() !== "hide")
   const [timestamps, setTimestamps] = kv.signal<"hide" | "show">("timestamps", "hide")
   const [showDetails, setShowDetails] = kv.signal("tool_details_visibility", true)
   const [showAssistantMetadata, _setShowAssistantMetadata] = kv.signal("assistant_metadata_visibility", true)
@@ -689,8 +689,9 @@ export function Session() {
     {
       title: (() => {
         const next = nextThinkingMode(thinkingMode())
-        if (next === "hide") return "Collapse thinking"
-        return "Expand thinking"
+        if (next === "minimal") return "Switch thinking to minimal"
+        if (next === "hide") return "Hide thinking"
+        return "Show thinking"
       })(),
       value: "session.toggle.thinking",
       category: "Session",
@@ -699,6 +700,16 @@ export function Session() {
         aliases: ["toggle-thinking"],
       },
       run: () => {
+        // Env override forces minimal for the process. Updating KV here would
+        // silently diverge from what's rendered; tell the user instead.
+        if (thinking.locked()) {
+          toast.show({
+            message: "Thinking mode is locked to minimal by OPENCODE_EXPERIMENTAL_MINIMAL_THINKING",
+            variant: "info",
+          })
+          dialog.clear()
+          return
+        }
         thinking.set(nextThinkingMode(thinkingMode()))
         dialog.clear()
       },
@@ -1501,7 +1512,7 @@ const PART_MAPPING = {
 function ReasoningPart(props: { last: boolean; part: ReasoningPart; message: AssistantMessage }) {
   const { theme, subtleSyntax } = useTheme()
   const ctx = use()
-  // Collapsed by default in hide mode: a single line throughout, so the
+  // Collapsed by default in minimal mode: a single line throughout, so the
   // layout never shifts. Click to open the full markdown block, click to close.
   const [expanded, setExpanded] = createSignal(false)
 
@@ -1512,7 +1523,7 @@ function ReasoningPart(props: { last: boolean; part: ReasoningPart; message: Ass
   // Reasoning is finalized when the server sets `time.end` (see processor.ts).
   // Flips independently of the parent message completing.
   const isDone = createMemo(() => props.part.time.end !== undefined)
-  const inMinimal = createMemo(() => ctx.thinkingMode() === "hide")
+  const inMinimal = createMemo(() => ctx.thinkingMode() === "minimal")
   const duration = createMemo(() => {
     const end = props.part.time.end
     return end === undefined ? 0 : Math.max(0, end - props.part.time.start)
@@ -1528,10 +1539,10 @@ function ReasoningPart(props: { last: boolean; part: ReasoningPart; message: Ass
   }
 
   return (
-    <Show when={content()}>
+    <Show when={content() && ctx.thinkingMode() !== "hide"}>
       <Switch>
         <Match when={!inMinimal() || expanded()}>
-          {/* Full markdown block: `show` mode, or `hide` after the user opens it. */}
+          {/* Full markdown block: `show` mode, or `minimal` after the user opens it. */}
           <box
             id={"text-" + props.part.id}
             paddingLeft={2}
@@ -1547,7 +1558,7 @@ function ReasoningPart(props: { last: boolean; part: ReasoningPart; message: Ass
               drawUnstyledText={false}
               streaming={true}
               syntaxStyle={subtleSyntax()}
-              content={(inMinimal() ? "▼ " : "") + (isDone() ? "_Thought:_ " : "_Thinking:_ ") + content()}
+              content={(inMinimal() ? "▼ " : "") + "_Thinking:_ " + content()}
               conceal={ctx.conceal()}
               fg={theme.textMuted}
             />

packages/opencode/src/cli/cmd/tui/thread.ts

@@ -9,6 +9,8 @@ import { errorMessage } from "@/util/error"
 import { withTimeout } from "@/util/timeout"
 import { withNetworkOptions, resolveNetworkOptionsNoConfig } from "@/cli/network"
 import { Filesystem } from "@/util/filesystem"
+import { ServerAuth } from "@/server/auth"
+import { ServerDiscovery } from "@/cli/server-discovery"
 import type { GlobalEvent } from "@opencode-ai/sdk/v2"
 import type { EventSource } from "./context/sdk"
 import { win32DisableProcessedInput, win32InstallCtrlCGuard } from "./win32"
@@ -197,16 +199,26 @@ export const TuiThreadCommand = cmd({
         network.mdns ||
         network.port !== 0 ||
         network.hostname !== "127.0.0.1"
+      const discovered = external ? undefined : await ServerDiscovery.find()
 
       const transport = external
         ? {
             url: (await client.call("server", network)).url,
             fetch: undefined,
+            headers: ServerAuth.headers(),
             events: undefined,
           }
+        : discovered
+          ? {
+              url: discovered,
+              fetch: undefined,
+              headers: ServerAuth.headers(),
+              events: undefined,
+            }
         : {
             url: "http://opencode.internal",
             fetch: createWorkerFetch(client),
+            headers: undefined,
             events: createEventSource(client),
           }
 
@@ -216,6 +228,7 @@ export const TuiThreadCommand = cmd({
           sessionID: args.session,
           directory: cwd,
           fetch: transport.fetch,
+          headers: transport.headers,
         })
       } catch (error) {
         UI.error(errorMessage(error))
@@ -239,6 +252,7 @@ export const TuiThreadCommand = cmd({
           config,
           directory: cwd,
           fetch: transport.fetch,
+          headers: transport.headers,
           events: transport.events,
           args: {
             continue: args.continue,

packages/opencode/src/cli/error.ts

@@ -2,9 +2,16 @@ import { NamedError } from "@opencode-ai/core/util/error"
 import { errorFormat } from "@/util/error"
 import { isRecord } from "@/util/record"
 
+interface ErrorLike {
+  name?: string
+  _tag?: string
+  message?: string
+  data?: Record<string, unknown>
+}
+
 type ConfigIssue = { message: string; path: string[] }
 
-function isTaggedError(error: unknown, tag: string): error is Record<string, unknown> {
+function isTaggedError(error: unknown, tag: string): boolean {
   return isRecord(error) && error._tag === tag
 }
 
@@ -32,27 +39,22 @@ function configIssues(input: Record<string, unknown>): ConfigIssue[] {
     : []
 }
 
-export function FormatError(input: unknown): string | undefined {
-  if (input instanceof Error && isRecord(input.cause) && "body" in input.cause) {
-    const formatted = FormatError(input.cause.body)
-    if (formatted) return formatted
-  }
-
+export function FormatError(input: unknown) {
   // CliError: domain failure surfaced from an effectCmd handler via fail("...")
   if (isTaggedError(input, "CliError")) {
-    if (typeof input.exitCode === "number") process.exitCode = input.exitCode
-    return stringField(input, "message") ?? ""
+    const data = input as ErrorLike & { exitCode?: number }
+    if (data.exitCode != null) process.exitCode = data.exitCode
+    return data.message ?? ""
   }
 
   // MCPFailed: { name: string }
   if (NamedError.hasName(input, "MCPFailed")) {
-    const data = isRecord(input) && isRecord(input.data) ? stringField(input.data, "name") : undefined
-    return `MCP server "${data}" failed. Note, opencode does not support MCP authentication yet.`
+    return `MCP server "${(input as ErrorLike).data?.name}" failed. Note, opencode does not support MCP authentication yet.`
   }
 
   // AccountServiceError, AccountTransportError: TaggedErrorClass
   if (isTaggedError(input, "AccountServiceError") || isTaggedError(input, "AccountTransportError")) {
-    return stringField(input, "message") ?? ""
+    return (input as ErrorLike).message ?? ""
   }
 
   // ProviderModelNotFoundError: { providerID: string, modelID: string, suggestions?: string[] }
@@ -62,7 +64,7 @@ export function FormatError(input: unknown): string | undefined {
       ? providerModelNotFound.suggestions.filter((x) => typeof x === "string")
       : []
     return [
-      `Model not found: ${stringField(providerModelNotFound, "providerID")}/${stringField(providerModelNotFound, "modelID")}`,
+      `Model not found: ${providerModelNotFound.providerID}/${providerModelNotFound.modelID}`,
       ...(suggestions.length ? ["Did you mean: " + suggestions.join(", ")] : []),
       `Try: \`opencode models\` to list available models`,
       `Or check your config (opencode.json) provider/model names`,
@@ -110,7 +112,6 @@ export function FormatError(input: unknown): string | undefined {
   if (isTaggedError(input, "UICancelledError") || NamedError.hasName(input, "UICancelledError")) {
     return ""
   }
-  return undefined
 }
 
 export function FormatUnknownError(input: unknown): string {

packages/opencode/src/cli/server-discovery.ts

@@ -0,0 +1,112 @@
+export * as ServerDiscovery from "./server-discovery"
+
+import { makeRuntime } from "@/effect/run-service"
+import { ServerAuth } from "@/server/auth"
+import { AppFileSystem } from "@opencode-ai/core/filesystem"
+import { Global } from "@opencode-ai/core/global"
+import { Context, Effect, Layer, Option, Schema } from "effect"
+import { readFileSync, unlinkSync } from "fs"
+import path from "path"
+
+export const file = path.join(Global.Path.state, "server.json")
+
+const Entry = Schema.Struct({
+  url: Schema.String,
+  pid: Schema.Number,
+})
+type Entry = typeof Entry.Type
+const decodeEntry = Schema.decodeUnknownOption(Entry)
+
+export interface Interface {
+  readonly write: (url: URL) => Effect.Effect<void>
+  readonly remove: () => Effect.Effect<void>
+  readonly find: () => Effect.Effect<string | undefined>
+}
+
+export class Service extends Context.Service<Service, Interface>()("@opencode/CliServerDiscovery") {}
+
+export const layer = Layer.effect(
+  Service,
+  Effect.gen(function* () {
+    const fs = yield* AppFileSystem.Service
+
+    const read = Effect.fn("CliServerDiscovery.read")(function* () {
+      const entry = yield* fs.readJson(file).pipe(Effect.catch(() => Effect.succeed(undefined)))
+      return Option.getOrUndefined(decodeEntry(entry))
+    })
+
+    const remove = Effect.fn("CliServerDiscovery.remove")(function* () {
+      const entry = yield* read()
+      if (entry?.pid !== process.pid) return
+      yield* fs.remove(file).pipe(Effect.ignore)
+    })
+
+    const removeStale = Effect.fn("CliServerDiscovery.removeStale")(function* (entry: Entry) {
+      const current = yield* read()
+      if (current?.pid !== entry.pid || current.url !== entry.url) return
+      yield* fs.remove(file).pipe(Effect.ignore)
+    })
+
+    return Service.of({
+      write: Effect.fn("CliServerDiscovery.write")(function* (url) {
+        yield* fs.writeJson(file, { url: localURL(url).toString(), pid: process.pid }, 0o600).pipe(Effect.orDie)
+      }),
+      remove,
+      find: Effect.fn("CliServerDiscovery.find")(function* () {
+        const entry = yield* read()
+        if (!entry) return undefined
+        const url = yield* healthy(entry.url)
+        if (url) return url
+        yield* removeStale(entry)
+      }),
+    })
+  }),
+)
+
+export const defaultLayer = layer.pipe(Layer.provide(AppFileSystem.defaultLayer))
+
+const { runPromise } = makeRuntime(Service, defaultLayer)
+
+export const find = () => runPromise((discovery) => discovery.find())
+
+export function removeSync() {
+  const entry = readSync()
+  if (entry?.pid !== process.pid) return
+  try {
+    unlinkSync(file)
+  } catch {}
+}
+
+function readSync() {
+  try {
+    return Option.getOrUndefined(decodeEntry(JSON.parse(readFileSync(file, "utf8"))))
+  } catch {
+    return undefined
+  }
+}
+
+function healthy(input: string) {
+  return Effect.tryPromise({
+    try: async () => {
+      const url = new URL(input)
+      if (url.protocol !== "http:" && url.protocol !== "https:") return undefined
+      const response = await fetch(new URL("/global/health", url), {
+        headers: ServerAuth.headers(),
+        signal: AbortSignal.timeout(1000),
+      })
+      if (!response.ok) return undefined
+      const body = (await response.json()) as unknown
+      if (typeof body === "object" && body !== null && "healthy" in body && body.healthy === true) {
+        return url.toString()
+      }
+    },
+    catch: () => undefined,
+  }).pipe(Effect.catch(() => Effect.succeed(undefined)))
+}
+
+function localURL(url: URL) {
+  const result = new URL(url)
+  if (result.hostname === "0.0.0.0") result.hostname = "127.0.0.1"
+  if (result.hostname === "::") result.hostname = "::1"
+  return result
+}

packages/opencode/src/server/routes/instance/httpapi/middleware/error.ts

@@ -1,6 +1,5 @@
 import { NamedError } from "@opencode-ai/core/util/error"
 import * as Log from "@opencode-ai/core/util/log"
-import { ConfigError } from "@/config/error"
 import { Cause, Effect } from "effect"
 import { HttpRouter, HttpServerError, HttpServerRespondable, HttpServerResponse } from "effect/unstable/http"
 
@@ -19,13 +18,6 @@ export const errorLayer = HttpRouter.middleware<{ handles: unknown }>()((effect)
       if (!defect) return Effect.failCause(cause)
 
       const error = defect.defect
-      if (
-        error instanceof NamedError &&
-        (ConfigError.InvalidError.isInstance(error) || ConfigError.JsonError.isInstance(error))
-      ) {
-        return Effect.succeed(HttpServerResponse.jsonUnsafe(error.toObject(), { status: 400 }))
-      }
-
       log.error("failed", { error, cause: Cause.pretty(cause) })
 
       return Effect.succeed(

packages/opencode/test/cli/cmd/tui/aggregate-failures.test.ts

@@ -5,7 +5,6 @@
  */
 import { describe, expect, test } from "bun:test"
 import { aggregateFailures } from "@/cli/cmd/tui/context/aggregate-failures"
-import { ConfigError } from "@/config/error"
 
 describe("aggregateFailures", () => {
   test("returns null when every result is fulfilled", () => {
@@ -42,48 +41,11 @@ describe("aggregateFailures", () => {
     expect(err!.message).toContain("agents: boom")
   })
 
-  test("formats structured config errors hidden inside SDK error causes", () => {
-    const configError = new ConfigError.InvalidError({
-      path: "/tmp/opencode.json",
-      issues: [{ message: "Expected object", path: ["provider", "anthropic", "options"] }],
-    })
-    const err = aggregateFailures([
-      {
-        name: "config.get",
-        result: {
-          status: "rejected",
-          reason: new Error("ConfigInvalidError", {
-            cause: {
-              body: configError.toObject(),
-            },
-          }),
-        },
-      },
-    ])
-
-    expect(err!.message).toContain("config.get: Configuration is invalid at /tmp/opencode.json")
-    expect(err!.message).toContain("Expected object provider.anthropic.options")
-  })
-
-  test("deduplicates identical failure messages across startup requests", () => {
-    const reason = new Error("same config problem")
-    const err = aggregateFailures([
-      { name: "config.providers", result: { status: "rejected", reason } },
-      { name: "provider.list", result: { status: "rejected", reason } },
-      { name: "app.agents", result: { status: "rejected", reason } },
-      { name: "config.get", result: { status: "rejected", reason } },
-      { name: "project.sync", result: { status: "fulfilled", value: undefined } },
-    ])
-
-    expect(err!.message).toContain("4 of 5 requests failed: same config problem")
-    expect(err!.message).toContain("Affected startup requests: config.providers, provider.list, app.agents, config.get")
-    expect(err!.message.match(/same config problem/g)?.length).toBe(1)
-  })
-
   test("attaches structured failure list under .cause", () => {
     const reason = new Error("nope")
     const err = aggregateFailures([{ name: "providers", result: { status: "rejected", reason } }])
-    expect(err!.cause).toEqual({ failures: [{ name: "providers", reason }] })
+    const cause = err!.cause as { failures: Array<{ name: string; reason: unknown }> }
+    expect(cause.failures).toEqual([{ name: "providers", reason }])
   })
 
   test("falls back to String() for opaque reasons", () => {

packages/opencode/test/server/httpapi-error-middleware.test.ts

@@ -1,7 +1,6 @@
 import { NodeHttpServer, NodeServices } from "@effect/platform-node"
 import { NamedError } from "@opencode-ai/core/util/error"
 import { describe, expect } from "bun:test"
-import { ConfigError } from "../../src/config/error"
 import { Effect, Layer } from "effect"
 import { HttpClient, HttpClientRequest, HttpRouter } from "effect/unstable/http"
 import { errorLayer } from "../../src/server/routes/instance/httpapi/middleware/error"
@@ -51,27 +50,6 @@ describe("HttpApi error middleware", () => {
     }),
   )
 
-  it.live("preserves config defects as client-visible bad requests", () =>
-    Effect.gen(function* () {
-      const configError = new ConfigError.InvalidError({
-        path: "/tmp/opencode.json",
-        issues: [{ message: "Expected object", path: ["provider", "anthropic", "options"] }],
-      })
-
-      yield* HttpRouter.add("GET", "/config-error", Effect.die(configError)).pipe(
-        Layer.provide(errorLayer),
-        HttpRouter.serve,
-        Layer.build,
-      )
-
-      const response = yield* HttpClientRequest.get("/config-error").pipe(HttpClient.execute)
-      const body = yield* response.json
-
-      expect(response.status).toBe(400)
-      expect(JSON.stringify(body)).toBe(JSON.stringify(configError.toObject()))
-    }),
-  )
-
   it.live("does not map storage not-found defects to 404", () =>
     Effect.gen(function* () {
       yield* HttpRouter.add(