diff --git a/packages/opencode/src/cli/cmd/tui/worker.ts b/packages/opencode/src/cli/cmd/tui/worker.ts
index e63f10ba80c..59ae94d7630 100644
--- a/packages/opencode/src/cli/cmd/tui/worker.ts
+++ b/packages/opencode/src/cli/cmd/tui/worker.ts
@@ -18,18 +18,19 @@ await Log.init({
     if (Installation.isLocal()) return "DEBUG"
     return "INFO"
   })(),
+  path: process.env.OPENCODE_LOG_PATH || undefined,
+  rotate:
+    process.env.OPENCODE_LOG_ROTATE === "daily"
+      ? { kind: "daily", retention: Number(process.env.OPENCODE_LOG_RETENTION) || undefined }
+      : undefined,
 })
 
 process.on("unhandledRejection", (e) => {
-  Log.Default.error("rejection", {
-    e: e instanceof Error ? e.message : e,
-  })
+  Log.Default.error("rejection", { error: e })
 })
 
 process.on("uncaughtException", (e) => {
-  Log.Default.error("exception", {
-    e: e instanceof Error ? e.message : e,
-  })
+  Log.Default.error("exception", { error: e })
 })
 
 // Subscribe to global events and forward them via RPC
diff --git a/packages/opencode/src/index.ts b/packages/opencode/src/index.ts
index 6dc5e99e91e..01ca8bf7c20 100644
--- a/packages/opencode/src/index.ts
+++ b/packages/opencode/src/index.ts
@@ -28,15 +28,11 @@ import { PrCommand } from "./cli/cmd/pr"
 import { SessionCommand } from "./cli/cmd/session"
 
 process.on("unhandledRejection", (e) => {
-  Log.Default.error("rejection", {
-    e: e instanceof Error ? e.message : e,
-  })
+  Log.Default.error("rejection", { error: e })
 })
 
 process.on("uncaughtException", (e) => {
-  Log.Default.error("exception", {
-    e: e instanceof Error ? e.message : e,
-  })
+  Log.Default.error("exception", { error: e })
 })
 
 const cli = yargs(hideBin(process.argv))
@@ -65,6 +61,11 @@ const cli = yargs(hideBin(process.argv))
         if (Installation.isLocal()) return "DEBUG"
         return "INFO"
       })(),
+      path: process.env.OPENCODE_LOG_PATH || undefined,
+      rotate:
+        process.env.OPENCODE_LOG_ROTATE === "daily"
+          ? { kind: "daily", retention: Number(process.env.OPENCODE_LOG_RETENTION) || undefined }
+          : undefined,
     })
 
     process.env.AGENT = "1"
diff --git a/packages/opencode/src/util/log.ts b/packages/opencode/src/util/log.ts
index 6941310bbbd..0ae727fa2aa 100644
--- a/packages/opencode/src/util/log.ts
+++ b/packages/opencode/src/util/log.ts
@@ -40,10 +40,22 @@ export namespace Log {
 
   export const Default = create({ service: "default" })
 
+  export type Rotate =
+    | {
+        kind: "startup"
+        retention?: number
+      }
+    | {
+        kind: "daily"
+        retention?: number
+      }
+
   export interface Options {
     print: boolean
     dev?: boolean
     level?: Level
+    path?: string
+    rotate?: Rotate
   }
 
   let logpath = ""
@@ -55,43 +67,86 @@ export namespace Log {
     return msg.length
   }
 
+  let current = ""
+  let writer: ReturnType<ReturnType<typeof Bun.file>["writer"]> | undefined
+
+  function today() {
+    const d = new Date()
+    return (
+      d.getFullYear() + "-" + String(d.getMonth() + 1).padStart(2, "0") + "-" + String(d.getDate()).padStart(2, "0")
+    )
+  }
+
+  function createWriter(filepath: string, truncate?: boolean) {
+    if (writer) writer.end()
+    logpath = filepath
+    if (truncate) fs.truncate(filepath).catch(() => {})
+    writer = Bun.file(filepath).writer()
+  }
+
+  function flushWriter(msg: any) {
+    const num = writer!.write(msg)
+    writer!.flush()
+    return num
+  }
+
+  function rotate(dir: string) {
+    const date = today()
+    if (date === current && writer) return
+    current = date
+    createWriter(path.join(dir, `opencode-${date}.log`))
+  }
+
+  const writeStrategies: Record<Rotate["kind"], (options: Options) => Promise<void>> = {
+    async startup(options) {
+      const dir = options.path ?? Global.Path.log
+      const retention = options.rotate?.retention ?? 10
+      cleanup(dir, "????-??-??T??????.log", retention)
+      const name = options.dev ? "dev.log" : new Date().toISOString().split(".")[0].replace(/:/g, "") + ".log"
+      createWriter(path.join(dir, name), true)
+      write = flushWriter
+    },
+    async daily(options) {
+      const dir = options.path ?? Global.Path.log
+      const retention = options.rotate?.retention ?? 7
+      await fs.mkdir(dir, { recursive: true })
+      rotate(dir)
+      cleanup(dir, "opencode-????-??-??.log", retention)
+      write = (msg: any) => {
+        rotate(dir)
+        return flushWriter(msg)
+      }
+    },
+  }
+
   export async function init(options: Options) {
     if (options.level) level = options.level
-    cleanup(Global.Path.log)
     if (options.print) return
-    logpath = path.join(
-      Global.Path.log,
-      options.dev ? "dev.log" : new Date().toISOString().split(".")[0].replace(/:/g, "") + ".log",
-    )
-    const logfile = Bun.file(logpath)
-    await fs.truncate(logpath).catch(() => {})
-    const writer = logfile.writer()
-    write = async (msg: any) => {
-      const num = writer.write(msg)
-      writer.flush()
-      return num
-    }
+    return writeStrategies[options.rotate?.kind ?? "startup"](options)
   }
 
-  async function cleanup(dir: string) {
-    const glob = new Bun.Glob("????-??-??T??????.log")
+  async function cleanup(dir: string, pattern: string, retention: number) {
+    const glob = new Bun.Glob(pattern)
     const files = await Array.fromAsync(
       glob.scan({
         cwd: dir,
         absolute: true,
       }),
     )
-    if (files.length <= 5) return
-
-    const filesToDelete = files.slice(0, -10)
+    if (files.length <= retention) return
+    files.sort()
+    const filesToDelete = files.slice(0, -retention)
     await Promise.all(filesToDelete.map((file) => fs.unlink(file).catch(() => {})))
   }
 
-  function formatError(error: Error, depth = 0): string {
-    const result = error.message
-    return error.cause instanceof Error && depth < 10
-      ? result + " Caused by: " + formatError(error.cause, depth + 1)
-      : result
+  function formatError(error: Error): string[] {
+    return Object.getOwnPropertyNames(error).flatMap((k) => {
+      const v = (error as any)[k]
+      if (v == null) return []
+      if (v instanceof Error) return [`${k}=${v.name}: ${v.message}`, ...formatError(v).map((s) => `${k}.${s}`)]
+      if (typeof v === "object") return [`${k}=${JSON.stringify(v)}`]
+      return [`${k}=${v}`]
+    })
   }
 
   let last = Date.now()
@@ -111,12 +166,11 @@ export namespace Log {
         ...tags,
         ...extra,
       })
-        .filter(([_, value]) => value !== undefined && value !== null)
-        .map(([key, value]) => {
-          const prefix = `${key}=`
-          if (value instanceof Error) return prefix + formatError(value)
-          if (typeof value === "object") return prefix + JSON.stringify(value)
-          return prefix + value
+        .flatMap(([key, value]) => {
+          if (value == null) return []
+          if (value instanceof Error) return formatError(value)
+          if (typeof value === "object") return [`${key}=${JSON.stringify(value)}`]
+          return [`${key}=${value}`]
         })
         .join(" ")
       const next = new Date()