diff --git a/src/Config.zig b/src/Config.zig
index c885f527..afe5459d 100644
--- a/src/Config.zig
+++ b/src/Config.zig
@@ -220,7 +220,6 @@ pub const Agent = struct {
     common: Common = .{},
     provider: AiProvider = .anthropic,
     model: ?[:0]const u8 = null,
-    api_key: ?[:0]const u8 = null,
     system_prompt: ?[:0]const u8 = null,
     repl: bool = true,
     script_file: ?[]const u8 = null,
@@ -501,11 +500,11 @@ pub fn printUsageAndExit(self: *const Config, success: bool) void {
         \\--model         The model name to use.
         \\                Defaults to a sensible default per provider.
         \\
-        \\--api-key       The API key. Can also be set via environment variable:
-        \\                ANTHROPIC_API_KEY, OPENAI_API_KEY, or GOOGLE_API_KEY.
-        \\
         \\--system-prompt Override the default system prompt.
         \\
+        \\The API key is read from the environment:
+        \\ANTHROPIC_API_KEY, OPENAI_API_KEY, or GOOGLE_API_KEY.
+        \\
     ++ common_options ++
         \\
         \\version command
@@ -927,15 +926,6 @@ fn parseAgentArgs(
             continue;
         }
 
-        if (std.mem.eql(u8, "--api-key", opt) or std.mem.eql(u8, "--api_key", opt)) {
-            const str = args.next() orelse {
-                log.fatal(.app, "missing argument value", .{ .arg = opt });
-                return error.InvalidArgument;
-            };
-            result.api_key = try allocator.dupeZ(u8, str);
-            continue;
-        }
-
         if (std.mem.eql(u8, "--repl", opt)) {
             result.repl = true;
             continue;
diff --git a/src/agent/Agent.zig b/src/agent/Agent.zig
index 84236dbd..0441b868 100644
--- a/src/agent/Agent.zig
+++ b/src/agent/Agent.zig
@@ -84,9 +84,9 @@ pub fn init(allocator: std.mem.Allocator, app: *App, opts: Config.Agent) !*Self
     const is_script_mode = opts.script_file != null;
 
     // API key is only required for REPL mode and self-healing
-    const api_key: ?[:0]const u8 = opts.api_key orelse getEnvApiKey(opts.provider) orelse if (!is_script_mode) {
+    const api_key: ?[:0]const u8 = getEnvApiKey(opts.provider) orelse if (!is_script_mode) {
         log.fatal(.app, "missing API key", .{
-            .hint = "Set the API key via --api-key or environment variable",
+            .hint = "Set ANTHROPIC_API_KEY, OPENAI_API_KEY, or GOOGLE_API_KEY",
         });
         return error.MissingApiKey;
     } else null;