configs/nixos/AGENTS.md

@@ -32,11 +32,11 @@
 
 - Use produced literals for Herdr key names that include shifted punctuation.
   For example, use `prefix+<` instead of `prefix+shift+comma`.
-- Put global Pi extension sources in `configs/nixos/modules/shell/pi/extensions/`.
-  Home Manager deploys them to `~/.pi/agent/extensions/`.
-- Treat Home Manager-managed Pi extension, prompt, and skill directories as generated output.
-  Do not edit those directories except for throwaway development or local experiments.
-  Promote finished work into the NixOS configuration before treating it as deployed.
+- Put monorepo Pi extension sources in `.pi/extensions/`.
+  Pi discovers them from subdirectories through the local ancestor-resource patch.
+- Treat Home Manager-managed Pi settings as generated output.
+  Do not edit them except for throwaway development or local experiments.
+  Promote finished settings into the NixOS configuration before treating them as deployed.
 
 ## Gotchas
 

configs/nixos/modules/shell/pi/default.nix

@@ -13,6 +13,7 @@ let
   piDir = "${config.users.users.${user}.home}/.pi/agent";
   patchedPi = pkgs.pi-coding-agent.overrideAttrs (old: {
     patches = (old.patches or [ ]) ++ [
+      ./patches/pi-project-resource-ancestors.patch
       ./patches/pi-tool-lookup-validation.patch
     ];
   });
@@ -44,12 +45,6 @@ in
         # The first declarative rollout replaces the interactive settings file.
         # Login state stays in auth.json, which this module does not manage.
         "${piDir}/settings.json".force = true;
-
-        "${piDir}/extensions" = {
-          source = ./extensions;
-          recursive = true;
-          force = true;
-        };
       };
     };
   };

configs/nixos/modules/shell/pi/patches/pi-project-resource-ancestors.patch

@@ -0,0 +1,140 @@
+diff --git a/packages/coding-agent/src/core/package-manager.ts b/packages/coding-agent/src/core/package-manager.ts
+--- a/packages/coding-agent/src/core/package-manager.ts
++++ b/packages/coding-agent/src/core/package-manager.ts
+@@ -459,14 +459,14 @@ function findGitRepoRoot(startDir: string): string | null {
+ 	}
+ }
+ 
+-function collectAncestorAgentsSkillDirs(startDir: string): string[] {
+-	const skillDirs: string[] = [];
++function collectAncestorConfigDirs(startDir: string, configDirName: string): string[] {
++	const configDirs: string[] = [];
+ 	const resolvedStartDir = resolve(startDir);
+ 	const gitRepoRoot = findGitRepoRoot(resolvedStartDir);
+ 
+ 	let dir = resolvedStartDir;
+ 	while (true) {
+-		skillDirs.push(join(dir, ".agents", "skills"));
++		configDirs.push(join(dir, configDirName));
+ 		if (gitRepoRoot && dir === gitRepoRoot) {
+ 			break;
+ 		}
+@@ -477,7 +477,7 @@ function collectAncestorAgentsSkillDirs(startDir: string): string[] {
+ 		dir = parent;
+ 	}
+ 
+-	return skillDirs;
++	return configDirs;
+ }
+ 
+ function collectAutoPromptEntries(dir: string): string[] {
+@@ -2388,16 +2388,13 @@ export class DefaultPackageManager implements PackageManager {
+ 			prompts: join(globalBaseDir, "prompts"),
+ 			themes: join(globalBaseDir, "themes"),
+ 		};
+-		const projectDirs = {
+-			extensions: join(projectBaseDir, "extensions"),
+-			skills: join(projectBaseDir, "skills"),
+-			prompts: join(projectBaseDir, "prompts"),
+-			themes: join(projectBaseDir, "themes"),
+-		};
+ 		const userAgentsSkillsDir = join(getHomeDir(), ".agents", "skills");
+ 		const projectTrusted = this.settingsManager.isProjectTrusted();
+-		const projectAgentsSkillDirs = projectTrusted
+-			? collectAncestorAgentsSkillDirs(this.cwd).filter((dir) => resolve(dir) !== resolve(userAgentsSkillsDir))
++		const projectConfigDirs = projectTrusted
++			? collectAncestorConfigDirs(this.cwd, CONFIG_DIR_NAME).filter((dir) => resolve(dir) !== resolve(globalBaseDir))
++			: [];
++		const projectAgentsDirs = projectTrusted
++			? collectAncestorConfigDirs(this.cwd, ".agents").filter((dir) => resolve(dir) !== resolve(dirname(userAgentsSkillsDir)))
+ 			: [];
+ 
+ 		const addResources = (
+@@ -2414,56 +2411,54 @@ export class DefaultPackageManager implements PackageManager {
+ 			}
+ 		};
+ 
+-		if (projectTrusted) {
+-			// Project extensions from .pi/
++		// Project resources from .pi/ in cwd and ancestors.
++		for (const configDir of projectConfigDirs) {
++			const configMetadata: PathMetadata = {
++				...projectMetadata,
++				baseDir: configDir,
++			};
+ 			addResources(
+ 				"extensions",
+-				collectAutoExtensionEntries(projectDirs.extensions),
+-				projectMetadata,
++				collectAutoExtensionEntries(join(configDir, "extensions")),
++				configMetadata,
+ 				projectOverrides.extensions,
+-				projectBaseDir,
++				configDir,
+ 			);
+-
+-			// Project skills from .pi/
+ 			addResources(
+ 				"skills",
+-				collectAutoSkillEntries(projectDirs.skills, "pi"),
+-				projectMetadata,
++				collectAutoSkillEntries(join(configDir, "skills"), "pi"),
++				configMetadata,
+ 				projectOverrides.skills,
+-				projectBaseDir,
++				configDir,
++			);
++			addResources(
++				"prompts",
++				collectAutoPromptEntries(join(configDir, "prompts")),
++				configMetadata,
++				projectOverrides.prompts,
++				configDir,
++			);
++			addResources(
++				"themes",
++				collectAutoThemeEntries(join(configDir, "themes")),
++				configMetadata,
++				projectOverrides.themes,
++				configDir,
+ 			);
+ 		}
+ 
+-		// Project skills from .agents/ (each with its own baseDir)
+-		for (const agentsSkillsDir of projectAgentsSkillDirs) {
+-			const agentsBaseDir = dirname(agentsSkillsDir); // the .agents directory
++		// Project skills from .agents/ in cwd and ancestors.
++		for (const agentsDir of projectAgentsDirs) {
+ 			const agentsMetadata: PathMetadata = {
+ 				...projectMetadata,
+-				baseDir: agentsBaseDir,
++				baseDir: agentsDir,
+ 			};
+ 			addResources(
+ 				"skills",
+-				collectAutoSkillEntries(agentsSkillsDir, "agents"),
++				collectAutoSkillEntries(join(agentsDir, "skills"), "agents"),
+ 				agentsMetadata,
+ 				projectOverrides.skills,
+-				agentsBaseDir,
+-			);
+-		}
+-
+-		if (projectTrusted) {
+-			addResources(
+-				"prompts",
+-				collectAutoPromptEntries(projectDirs.prompts),
+-				projectMetadata,
+-				projectOverrides.prompts,
+-				projectBaseDir,
+-			);
+-			addResources(
+-				"themes",
+-				collectAutoThemeEntries(projectDirs.themes),
+-				projectMetadata,
+-				projectOverrides.themes,
+-				projectBaseDir,
++				agentsDir,
+ 			);
+ 		}
+