fix: Config.update() writes to wrong file, PATCH /config settings silently lost

packages/drivers/src/sqlserver.ts

@@ -7,7 +7,6 @@ import type { ConnectionConfig, Connector, ConnectorResult, SchemaColumn } from
 export async function connect(config: ConnectionConfig): Promise<Connector> {
   let mssql: any
   try {
-    // @ts-expect-error — mssql has no type declarations; installed as optional peerDependency
     mssql = await import("mssql")
     mssql = mssql.default || mssql
   } catch {

packages/opencode/src/config/config.ts

@@ -1425,7 +1425,11 @@ export namespace Config {
   }
 
   export async function update(config: Info) {
-    const filepath = path.join(Instance.directory, "config.json")
+    // Find an existing project config file, or default to opencode.json.
+    // ConfigPaths.projectFiles("opencode", ...) looks for opencode.jsonc and opencode.json,
+    // so we must write to one of those — not config.json which is never loaded by state().
+    const projectFiles = await ConfigPaths.projectFiles("opencode", Instance.directory, Instance.worktree)
+    const filepath = projectFiles[projectFiles.length - 1] ?? path.join(Instance.directory, "opencode.json")
     const existing = await loadFile(filepath)
     await Filesystem.writeJson(filepath, mergeDeep(existing, config))
     await Instance.dispose()

packages/opencode/test/config/config.test.ts

@@ -699,7 +699,7 @@ test("updates config and writes to file", async () => {
       const newConfig = { model: "updated/model" }
       await Config.update(newConfig as any)
 
-      const writtenConfig = await Filesystem.readJson(path.join(tmp.path, "config.json"))
+      const writtenConfig = await Filesystem.readJson(path.join(tmp.path, "opencode.json"))
       expect(writtenConfig.model).toBe("updated/model")
     },
   })