fix(server): theme set help names which clients apply the theme

apps/server/src/cli/theme.ts

@@ -408,7 +408,9 @@ const themeSetCommand = Command.make("set", {
     ),
   ),
 }).pipe(
-  Command.withDescription("Set the environment's theme; connected clients switch to it."),
+  Command.withDescription(
+    "Set the environment's theme. The web app this server serves and the desktop app on this machine switch to it; a desktop app connected from another machine does not.",
+  ),
   Command.withHandler((flags) =>
     Effect.gen(function* () {
       const fs = yield* FileSystem.FileSystem;

apps/server/src/mcp/toolkits/theme/tools.ts

@@ -53,7 +53,7 @@ const ThemeReadTool = Tool.make("t3_theme_read", {
 const ThemeSetTool = Tool.make("t3_theme_set", {
   ...shared,
   description:
-    "Restyle T3 Code itself, only when the user asks. With `theme`, publish it as `themeId` (the same id updates it) and switch this machine's web and desktop clients to it. Without `theme`, switch to a built-in or published `themeId`. `appearance` switches them to light, dark, or system mode, with or without a theme. Live full-access or default caller thread only.",
+    "Restyle T3 Code itself, only when the user asks. With `theme`, publish it as `themeId` (same id updates it) and switch this server's web app and this machine's desktop app to it, not remote desktop apps. Without `theme`, switch to a built-in or published `themeId`. `appearance` sets light, dark, or system mode. Live full-access or default caller thread only.",
   parameters: Schema.Struct({
     themeId: Schema.optionalKey(EnvironmentThemeId),
     theme: Schema.optionalKey(EnvironmentThemeFile),

apps/server/src/provider/agentContextBudget.json

@@ -1,5 +1,5 @@
 {
   "claudeSystemAppendBytes": 5930,
   "codexAdditionalContextBytes": 7324,
-  "mcpToolListJsonBytes": 49738
+  "mcpToolListJsonBytes": 49736
 }

evals/mcp-tool-use/cases/themes.ndjson

@@ -1,3 +1,3 @@
 {"id": "restyle-t3-code-uses-theme-set", "area": "themes", "kind": "guard", "pattern": "restyle T3 Code itself", "experience": "Asked to change how T3 Code itself looks, an agent reads the theme guide, then publishes a theme with t3_theme_set. It does not write theme files by hand or edit the project.", "rule": "t3_theme_set: Restyle T3 Code itself, only when the user asks.", "privacy": "commit-safe", "source": {"pullRequest": "https://github.com/pingdotgg/t3code/pull/29293", "note": "A user needed a look the app had no setting for."}, "setup": {"role": "top", "mocks": {"t3_theme_read": {"current": "", "builtIn": ["t3-chat", "grove", "ocean", "ember", "iris"], "published": [], "guide": "Themes restyle T3 Code on web and desktop. `canvas` and `accent` (hex) derive a full palette. `css` applies after the app's styles."}, "t3_theme_set": {"themeId": "night-terminal", "published": true}}}, "prompt": "Make T3 Code itself look like a late-night terminal: near-black background with a green accent.", "expect": {"calls": [{"tool": "t3_theme_set", "args": {"theme.appearance": "dark"}}], "order": ["t3_theme_read", "t3_theme_set"]}, "maxSteps": 6}
 {"id": "control-project-theme-edit-leaves-t3-code-alone", "area": "themes", "kind": "control", "pattern": "ordinary task: edit the project's own theme", "experience": "The user's project has a theme of its own. A request to change it is a file edit. T3 Code's look must not change.", "rule": "t3_theme_set: Restyle T3 Code itself, only when the user asks.", "privacy": "commit-safe", "setup": {"role": "top", "world": {"files": {"src/theme.css": ":root { --accent: #3b82f6; }\n.dark { --accent: #60a5fa; }\n"}}}, "prompt": "Change the dark theme accent to green.", "expect": {"notCalls": ["t3_theme_set", "t3_theme_read"], "textMust": ["theme\\.css"]}, "maxSteps": 6, "source": {"pullRequest": "https://github.com/pingdotgg/t3code/pull/35247", "note": "A real Haiku turn in the dev app during this work: asked to change a project's theme file, it edited the file and left T3 Code alone."}}
-{"id": "dark-mode-request-sets-appearance", "area": "themes", "kind": "guard", "pattern": "switch T3 Code to dark mode", "experience": "Asked to switch T3 Code to dark mode, an agent sets the appearance with t3_theme_set. It does not tell the user to do it by hand, and it does not publish a new theme.", "rule": "t3_theme_set: `appearance` switches them to light, dark, or system mode, with or without a theme.", "privacy": "commit-safe", "source": {"pullRequest": "https://github.com/pingdotgg/t3code/pull/35247", "note": "In the dev app, an agent asked to swap to dark mode said it could not and sent the user to Settings."}, "setup": {"role": "top", "mocks": {"t3_theme_read": {"current": "sumi", "builtIn": ["t3-chat", "grove", "ocean", "ember", "iris"], "published": [{"id": "sumi", "name": "Sumi", "hasCss": true}], "guide": "Themes restyle T3 Code on web and desktop."}, "t3_theme_set": {"appearance": "dark", "published": false}}}, "prompt": "swap me to dark mode", "expect": {"calls": [{"tool": "t3_theme_set", "args": {"appearance": "dark"}}]}, "maxSteps": 4}
+{"id": "dark-mode-request-sets-appearance", "area": "themes", "kind": "guard", "pattern": "switch T3 Code to dark mode", "experience": "Asked to switch T3 Code to dark mode, an agent sets the appearance with t3_theme_set. It does not tell the user to do it by hand, and it does not publish a new theme.", "rule": "t3_theme_set: `appearance` sets light, dark, or system mode.", "privacy": "commit-safe", "source": {"pullRequest": "https://github.com/pingdotgg/t3code/pull/35247", "note": "In the dev app, an agent asked to swap to dark mode said it could not and sent the user to Settings."}, "setup": {"role": "top", "mocks": {"t3_theme_read": {"current": "sumi", "builtIn": ["t3-chat", "grove", "ocean", "ember", "iris"], "published": [{"id": "sumi", "name": "Sumi", "hasCss": true}], "guide": "Themes restyle T3 Code on web and desktop."}, "t3_theme_set": {"appearance": "dark", "published": false}}}, "prompt": "swap me to dark mode", "expect": {"calls": [{"tool": "t3_theme_set", "args": {"appearance": "dark"}}]}, "maxSteps": 4}