diff --git a/hosts/index.ts b/hosts/index.ts
index cc1c213b53..18728b6eb0 100644
--- a/hosts/index.ts
+++ b/hosts/index.ts
@@ -16,9 +16,10 @@ import cursor from './cursor';
 import openclaw from './openclaw';
 import hermes from './hermes';
 import gbrain from './gbrain';
+import pi from './pi';
 
 /** All registered host configs. Add new hosts here. */
-export const ALL_HOST_CONFIGS: HostConfig[] = [claude, codex, factory, kiro, opencode, slate, cursor, openclaw, hermes, gbrain];
+export const ALL_HOST_CONFIGS: HostConfig[] = [claude, codex, factory, kiro, opencode, slate, cursor, openclaw, hermes, gbrain, pi];
 
 /** Map from host name to config. */
 export const HOST_CONFIG_MAP: Record<string, HostConfig> = Object.fromEntries(
@@ -65,4 +66,4 @@ export function getExternalHosts(): HostConfig[] {
 }
 
 // Re-export individual configs for direct import
-export { claude, codex, factory, kiro, opencode, slate, cursor, openclaw, hermes, gbrain };
+export { claude, codex, factory, kiro, opencode, slate, cursor, openclaw, hermes, gbrain, pi };
diff --git a/hosts/pi.ts b/hosts/pi.ts
new file mode 100644
index 0000000000..663f29cadf
--- /dev/null
+++ b/hosts/pi.ts
@@ -0,0 +1,49 @@
+import type { HostConfig } from '../scripts/host-config';
+
+const pi: HostConfig = {
+  name: 'pi',
+  displayName: 'Pi Coding Agent',
+  cliCommand: 'pi',
+  cliAliases: [],
+
+  globalRoot: '.pi/agent/skills/gstack',
+  localSkillRoot: '.pi/skills/gstack',
+  hostSubdir: '.pi',
+  usesEnvVars: true,
+
+  frontmatter: {
+    mode: 'allowlist',
+    keepFields: ['name', 'description'],
+    descriptionLimit: 1024,
+    descriptionLimitBehavior: 'warn',
+  },
+
+  generation: {
+    generateMetadata: false,
+    skipSkills: ['codex'],
+  },
+
+  pathRewrites: [
+    { from: '~/.claude/skills/gstack', to: '~/.pi/agent/skills/gstack' },
+    { from: '.claude/skills/gstack', to: '.pi/skills/gstack' },
+    { from: '.claude/skills', to: '.pi/skills' },
+  ],
+
+  suppressedResolvers: ['GBRAIN_CONTEXT_LOAD', 'GBRAIN_SAVE_RESULTS'],
+
+  runtimeRoot: {
+    globalSymlinks: ['bin', 'browse/dist', 'browse/bin', 'design/dist', 'gstack-upgrade', 'ETHOS.md', 'review/specialists', 'qa/templates', 'qa/references', 'plan-devex-review/dx-hall-of-fame.md'],
+    globalFiles: {
+      'review': ['checklist.md', 'design-checklist.md', 'greptile-triage.md', 'TODOS-format.md'],
+    },
+  },
+
+  install: {
+    prefixable: false,
+    linkingStrategy: 'symlink-generated',
+  },
+
+  learningsMode: 'basic',
+};
+
+export default pi;
diff --git a/setup b/setup
index f812511e4d..e7233550c0 100755
--- a/setup
+++ b/setup
@@ -24,6 +24,8 @@ FACTORY_SKILLS="$HOME/.factory/skills"
 FACTORY_GSTACK="$FACTORY_SKILLS/gstack"
 OPENCODE_SKILLS="$HOME/.config/opencode/skills"
 OPENCODE_GSTACK="$OPENCODE_SKILLS/gstack"
+PI_SKILLS="$HOME/.pi/agent/skills"
+PI_GSTACK="$PI_SKILLS/gstack"
 
 IS_WINDOWS=0
 case "$(uname -s)" in
@@ -43,7 +45,7 @@ TEAM_MODE=0
 NO_TEAM_MODE=0
 while [ $# -gt 0 ]; do
   case "$1" in
-    --host) [ -z "$2" ] && echo "Missing value for --host (expected claude, codex, kiro, factory, opencode, openclaw, hermes, gbrain, or auto)" >&2 && exit 1; HOST="$2"; shift 2 ;;
+    --host) [ -z "$2" ] && echo "Missing value for --host (expected claude, codex, kiro, factory, opencode, openclaw, hermes, gbrain, pi, or auto)" >&2 && exit 1; HOST="$2"; shift 2 ;;
     --host=*) HOST="${1#--host=}"; shift ;;
     --local) LOCAL_INSTALL=1; shift ;;
     --prefix)    SKILL_PREFIX=1; SKILL_PREFIX_FLAG=1; shift ;;
@@ -56,7 +58,7 @@ while [ $# -gt 0 ]; do
 done
 
 case "$HOST" in
-  claude|codex|kiro|factory|opencode|auto) ;;
+  claude|codex|kiro|factory|opencode|pi|auto) ;;
   openclaw)
     echo ""
     echo "OpenClaw integration uses a different model — OpenClaw spawns Claude Code"
@@ -91,7 +93,7 @@ case "$HOST" in
     echo "GBrain setup and brain skills ship from the GBrain repo."
     echo ""
     exit 0 ;;
-  *) echo "Unknown --host value: $HOST (expected claude, codex, kiro, factory, opencode, openclaw, hermes, gbrain, or auto)" >&2; exit 1 ;;
+  *) echo "Unknown --host value: $HOST (expected claude, codex, kiro, factory, opencode, openclaw, hermes, gbrain, pi, or auto)" >&2; exit 1 ;;
 esac
 
 # ─── Resolve skill prefix preference ─────────────────────────
@@ -155,14 +157,16 @@ INSTALL_CODEX=0
 INSTALL_KIRO=0
 INSTALL_FACTORY=0
 INSTALL_OPENCODE=0
+INSTALL_PI=0
 if [ "$HOST" = "auto" ]; then
   command -v claude >/dev/null 2>&1 && INSTALL_CLAUDE=1
   command -v codex >/dev/null 2>&1 && INSTALL_CODEX=1
   command -v kiro-cli >/dev/null 2>&1 && INSTALL_KIRO=1
   command -v droid >/dev/null 2>&1 && INSTALL_FACTORY=1
   command -v opencode >/dev/null 2>&1 && INSTALL_OPENCODE=1
+  command -v pi >/dev/null 2>&1 && INSTALL_PI=1
   # If none found, default to claude
-  if [ "$INSTALL_CLAUDE" -eq 0 ] && [ "$INSTALL_CODEX" -eq 0 ] && [ "$INSTALL_KIRO" -eq 0 ] && [ "$INSTALL_FACTORY" -eq 0 ] && [ "$INSTALL_OPENCODE" -eq 0 ]; then
+  if [ "$INSTALL_CLAUDE" -eq 0 ] && [ "$INSTALL_CODEX" -eq 0 ] && [ "$INSTALL_KIRO" -eq 0 ] && [ "$INSTALL_FACTORY" -eq 0 ] && [ "$INSTALL_OPENCODE" -eq 0 ] && [ "$INSTALL_PI" -eq 0 ]; then
     INSTALL_CLAUDE=1
   fi
 elif [ "$HOST" = "claude" ]; then
@@ -175,6 +179,8 @@ elif [ "$HOST" = "factory" ]; then
   INSTALL_FACTORY=1
 elif [ "$HOST" = "opencode" ]; then
   INSTALL_OPENCODE=1
+elif [ "$HOST" = "pi" ]; then
+  INSTALL_PI=1
 fi
 
 migrate_direct_codex_install() {
@@ -311,6 +317,17 @@ if [ "$INSTALL_FACTORY" -eq 1 ] && [ "$NEEDS_BUILD" -eq 0 ]; then
   )
 fi
 
+# 1e. Generate .pi/ Pi skill docs
+if [ "$INSTALL_PI" -eq 1 ] && [ "$NEEDS_BUILD" -eq 0 ]; then
+  log "Generating .pi/ skill docs..."
+  (
+    cd "$SOURCE_GSTACK_DIR"
+    bun install --frozen-lockfile 2>/dev/null || bun install
+    bun run gen:skill-docs --host pi
+  )
+fi
+
+
 # 1d. Generate .opencode/ OpenCode skill docs
 if [ "$INSTALL_OPENCODE" -eq 1 ] && [ "$NEEDS_BUILD" -eq 0 ]; then
   log "Generating .opencode/ skill docs..."
@@ -763,6 +780,92 @@ link_opencode_skill_dirs() {
   fi
 }
 
+create_pi_runtime_root() {
+  local gstack_dir="$1"
+  local pi_gstack="$2"
+  local pi_dir="$gstack_dir/.pi/skills"
+
+  if [ -L "$pi_gstack" ]; then
+    rm -f "$pi_gstack"
+  elif [ -d "$pi_gstack" ] && [ "$pi_gstack" != "$gstack_dir" ]; then
+    rm -rf "$pi_gstack"
+  fi
+
+  mkdir -p "$pi_gstack" "$pi_gstack/browse" "$pi_gstack/design" "$pi_gstack/gstack-upgrade" "$pi_gstack/review" "$pi_gstack/qa" "$pi_gstack/plan-devex-review"
+
+  if [ -f "$pi_dir/gstack/SKILL.md" ]; then
+    ln -snf "$pi_dir/gstack/SKILL.md" "$pi_gstack/SKILL.md"
+  fi
+  if [ -d "$gstack_dir/bin" ]; then
+    ln -snf "$gstack_dir/bin" "$pi_gstack/bin"
+  fi
+  if [ -d "$gstack_dir/browse/dist" ]; then
+    ln -snf "$gstack_dir/browse/dist" "$pi_gstack/browse/dist"
+  fi
+  if [ -d "$gstack_dir/browse/bin" ]; then
+    ln -snf "$gstack_dir/browse/bin" "$pi_gstack/browse/bin"
+  fi
+  if [ -d "$gstack_dir/design/dist" ]; then
+    ln -snf "$gstack_dir/design/dist" "$pi_gstack/design/dist"
+  fi
+  if [ -f "$pi_dir/gstack-upgrade/SKILL.md" ]; then
+    ln -snf "$pi_dir/gstack-upgrade/SKILL.md" "$pi_gstack/gstack-upgrade/SKILL.md"
+  fi
+  for f in checklist.md design-checklist.md greptile-triage.md TODOS-format.md; do
+    if [ -f "$gstack_dir/review/$f" ]; then
+      ln -snf "$gstack_dir/review/$f" "$pi_gstack/review/$f"
+    fi
+  done
+  if [ -d "$gstack_dir/review/specialists" ]; then
+    ln -snf "$gstack_dir/review/specialists" "$pi_gstack/review/specialists"
+  fi
+  if [ -d "$gstack_dir/qa/templates" ]; then
+    ln -snf "$gstack_dir/qa/templates" "$pi_gstack/qa/templates"
+  fi
+  if [ -d "$gstack_dir/qa/references" ]; then
+    ln -snf "$gstack_dir/qa/references" "$pi_gstack/qa/references"
+  fi
+  if [ -f "$gstack_dir/plan-devex-review/dx-hall-of-fame.md" ]; then
+    ln -snf "$gstack_dir/plan-devex-review/dx-hall-of-fame.md" "$pi_gstack/plan-devex-review/dx-hall-of-fame.md"
+  fi
+  if [ -f "$gstack_dir/ETHOS.md" ]; then
+    ln -snf "$gstack_dir/ETHOS.md" "$pi_gstack/ETHOS.md"
+  fi
+}
+
+link_pi_skill_dirs() {
+  local gstack_dir="$1"
+  local skills_dir="$2"
+  local pi_dir="$gstack_dir/.pi/skills"
+  local linked=()
+
+  if [ ! -d "$pi_dir" ]; then
+    echo "  Generating .pi/ skill docs..."
+    ( cd "$gstack_dir" && bun run gen:skill-docs --host pi )
+  fi
+
+  if [ ! -d "$pi_dir" ]; then
+    echo "  warning: .pi/skills/ generation failed — run 'bun run gen:skill-docs --host pi' manually" >&2
+    return 1
+  fi
+
+  for skill_dir in "$pi_dir"/gstack*/; do
+    if [ -f "$skill_dir/SKILL.md" ]; then
+      skill_name="$(basename "$skill_dir")"
+      [ "$skill_name" = "gstack" ] && continue
+      target="$skills_dir/$skill_name"
+      if [ -L "$target" ] || [ ! -e "$target" ]; then
+        ln -snf "$skill_dir" "$target"
+        linked+=("$skill_name")
+      fi
+    fi
+  done
+  if [ ${#linked[@]} -gt 0 ]; then
+    echo "  linked skills: ${linked[*]}"
+  fi
+}
+
+
 # 4. Install for Claude (default)
 SKILLS_BASENAME="$(basename "$INSTALL_SKILLS_DIR")"
 SKILLS_PARENT_BASENAME="$(basename "$(dirname "$INSTALL_SKILLS_DIR")")"
@@ -968,6 +1071,17 @@ if [ "$INSTALL_OPENCODE" -eq 1 ]; then
   echo "  opencode skills: $OPENCODE_SKILLS"
 fi
 
+# 6d. Install for Pi Coding Agent
+if [ "$INSTALL_PI" -eq 1 ]; then
+  mkdir -p "$PI_SKILLS"
+  create_pi_runtime_root "$SOURCE_GSTACK_DIR" "$PI_GSTACK"
+  link_pi_skill_dirs "$SOURCE_GSTACK_DIR" "$PI_SKILLS"
+  echo "gstack ready (pi)."
+  echo "  browse: $BROWSE_BIN"
+  echo "  pi skills: $PI_SKILLS"
+fi
+
+
 # 7. Create .agents/ sidecar symlinks for the real Codex skill target.
 # The root Codex skill ends up pointing at $SOURCE_GSTACK_DIR/.agents/skills/gstack,
 # so the runtime assets must live there for both global and repo-local installs.