diff --git a/.claude-plugin/plugin.json b/.claude-plugin/plugin.json
index c75259f..34aa46b 100644
--- a/.claude-plugin/plugin.json
+++ b/.claude-plugin/plugin.json
@@ -1,6 +1,6 @@
 {
   "name": "compose-expert",
-  "version": "2.3.0",
+  "version": "2.3.1",
   "description": "Compose and Compose Multiplatform expert skill — state, animations, navigation, performance, design-to-code, PR review mode, M3 motion.",
   "author": {
     "name": "Adit Lal",
diff --git a/.copilot/plugin.yaml b/.copilot/plugin.yaml
index 9980e39..61c0a79 100644
--- a/.copilot/plugin.yaml
+++ b/.copilot/plugin.yaml
@@ -1,5 +1,5 @@
 name: compose-expert
-version: 2.3.0
+version: 2.3.1
 description: >
   Compose and Compose Multiplatform expert skill — state, animations, navigation,
   performance, design-to-code, PR review mode, M3 motion.
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c4906b8..124d1b1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,6 +22,9 @@ jobs:
       - name: Validate plugin manifest schema
         run: bash scripts/validate-plugin-manifest.sh
 
+      - name: Check SKILL.md description length (Codex/Copilot 1024-char cap)
+        run: bash scripts/check-description-length.sh
+
       - name: Run manifest schema tests
         run: bats scripts/validate-plugin-manifest.bats
 
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index f2d1b3f..7511500 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -22,6 +22,9 @@ jobs:
       - name: Validate plugin manifest schema
         run: bash scripts/validate-plugin-manifest.sh
 
+      - name: Check SKILL.md description length (Codex/Copilot 1024-char cap)
+        run: bash scripts/check-description-length.sh
+
       - name: Assert version consistency
         run: bash scripts/check-versions.sh "${GITHUB_REF_NAME}"
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index b67fde7..391ac94 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,33 @@
 
 All notable changes to this project will be documented in this file.
 
+## [2.3.1] - 2026-05-03
+
+### Fixed
+
+- **`SKILL.md` `description:` frontmatter no longer exceeds Codex / Copilot
+  CLI's 1024-character cap** (issue #12). Both hosts rejected the manifest
+  with `invalid description: exceeds maximum length of 1024 characters`. The
+  field is now 843 chars; Claude Code continues to load it identically.
+
+### Changed
+
+- Long trigger-keyword surface previously packed into the `description:`
+  field (TV phrases, casual phrasings, Compose Multiplatform symbol lists,
+  Review Mode triggers) is preserved in a new **`## When this skill applies`**
+  section in the SKILL.md body. Body content is not subject to the 1024-char
+  cap, so the keyword surface remains available to Claude after the skill
+  loads.
+
+### Added
+
+- **`scripts/check-description-length.sh`** — a regression check that
+  asserts the SKILL.md frontmatter `description:` is ≤ 1024 chars.
+- Wired the new check into both `.github/workflows/ci.yml` (every PR) and
+  `.github/workflows/release.yml` (every tag push) so a future regression
+  fails CI loudly instead of shipping green on Claude Code and breaking
+  Codex / Copilot installs.
+
 ## [2.3.0] - 2026-05-03
 
 ### Added
diff --git a/scripts/check-description-length.sh b/scripts/check-description-length.sh
new file mode 100755
index 0000000..209542d
--- /dev/null
+++ b/scripts/check-description-length.sh
@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Asserts the SKILL.md frontmatter `description:` field is <= 1024 characters.
+# Codex CLI and Copilot CLI both reject the manifest when this field exceeds
+# 1024 characters (see issue #12). Claude Code does not enforce the cap, so
+# without this check a regression ships green on Claude and breaks downstream.
+
+SKILL_FILE="${1:-skills/compose-expert/SKILL.md}"
+LIMIT=1024
+
+if [[ ! -f "$SKILL_FILE" ]]; then
+  echo "FAIL: $SKILL_FILE not found"
+  exit 1
+fi
+
+# Extract the description: block from the frontmatter (between first two `---`).
+# Handles both inline (`description: ...`) and folded (`description: >\n  ...`)
+# YAML forms. Stops at the next top-level frontmatter key.
+desc=$(awk '
+  /^---$/ { c++; next }
+  c == 1 && /^description:/ {
+    flag = 1
+    sub(/^description: */, "")
+    print
+    next
+  }
+  c == 1 && flag && /^[a-zA-Z_]+:/ { exit }
+  c == 1 && flag { print }
+' "$SKILL_FILE")
+
+len=${#desc}
+
+if (( len > LIMIT )); then
+  echo "FAIL: description is $len chars, exceeds $LIMIT-char Codex/Copilot limit"
+  echo "      file: $SKILL_FILE"
+  echo "      issue: https://github.com/aldefy/compose-skill/issues/12"
+  exit 1
+fi
+
+echo "OK: description is $len chars (limit $LIMIT)"
diff --git a/scripts/check-versions.bats b/scripts/check-versions.bats
index b282d6d..a427cf8 100644
--- a/scripts/check-versions.bats
+++ b/scripts/check-versions.bats
@@ -4,6 +4,9 @@ setup() {
   TEST_DIR=$(mktemp -d)
   cp -R "$BATS_TEST_DIRNAME/.." "$TEST_DIR/repo"
   cd "$TEST_DIR/repo"
+  # Read the current version from plugin.json so the test does not rot at
+  # every release. Tests verify the script's logic, not a fixed version.
+  CURRENT=$(jq -r .version .claude-plugin/plugin.json)
 }
 
 teardown() {
@@ -11,21 +14,21 @@ teardown() {
 }
 
 @test "passes when all five versions match (tag passed as arg)" {
-  run bash scripts/check-versions.sh v2.1.2
+  run bash scripts/check-versions.sh "v${CURRENT}"
   [ "$status" -eq 0 ]
   [[ "$output" == *"versions aligned"* ]]
 }
 
 @test "fails when plugin.json version diverges" {
-  sed -i.bak 's/"version": "2.1.2"/"version": "2.0.1"/' .claude-plugin/plugin.json
-  run bash scripts/check-versions.sh v2.1.2
+  sed -i.bak "s/\"version\": \"${CURRENT}\"/\"version\": \"0.0.1\"/" .claude-plugin/plugin.json
+  run bash scripts/check-versions.sh "v${CURRENT}"
   [ "$status" -ne 0 ]
   [[ "$output" == *"plugin.json"* ]]
 }
 
 @test "fails when SKILL.md frontmatter version diverges" {
-  sed -i.bak 's/^version: 2.1.2$/version: 2.0.1/' skills/compose-expert/SKILL.md
-  run bash scripts/check-versions.sh v2.1.2
+  sed -i.bak "s/^version: ${CURRENT}$/version: 0.0.1/" skills/compose-expert/SKILL.md
+  run bash scripts/check-versions.sh "v${CURRENT}"
   [ "$status" -ne 0 ]
   [[ "$output" == *"SKILL.md"* ]]
 }
diff --git a/skills/compose-expert/SKILL.md b/skills/compose-expert/SKILL.md
index 91e35e8..ea7b45f 100644
--- a/skills/compose-expert/SKILL.md
+++ b/skills/compose-expert/SKILL.md
@@ -1,27 +1,18 @@
 ---
 name: compose-expert
 description: >
-  Compose and Compose Multiplatform expert skill for UI development across Android, Desktop,
-  iOS, and Web. Guides state management, view composition, animations, navigation, performance,
-  design-to-code workflows, and production crash patterns. Backed by actual source code analysis
-  from both androidx/androidx and JetBrains/compose-multiplatform-core.
-  Use this skill whenever the user mentions Compose, @Composable, remember, LaunchedEffect,
-  Scaffold, NavHost, MaterialTheme, LazyColumn, Modifier, recomposition, Style, styleable,
-  MutableStyleState, Compose Multiplatform, CMP, KMP, commonMain, expect, actual,
-  ComposeUIViewController, Window composable, UIKitView, ComposeViewport, Res.drawable,
-  Res.string, or any Compose API. Also trigger when the user says "Android UI", "Kotlin UI",
-  "compose layout", "compose navigation", "compose animation", "material3", "compose styles",
-  "compose multiplatform", "desktop compose", "iOS compose", "compose web", "design to compose",
-  "build this UI", "implement this design", "Android TV", "Google TV", "tv-material",
-  "tv-foundation", "Carousel", "NavigationDrawer", "D-pad", "focus indication",
-  "10-foot UI", "living room", "tv compose", "review this PR", "review this code",
-  "check this diff", or any GitHub PR URL (github.com/.*/pull/),
-  "design system", "component library", "atomic", "reusable component",
-  "design tokens", "atoms", "molecules", or asks about modern
-  Kotlin UI development patterns. Even casual mentions like "my compose screen is slow"
-  or "how do I pass data between screens" or "how do I build a TV app" should trigger this skill.
-  Also trigger on session_start to auto-detect Compose projects — see references/auto-init.md.
-version: 2.3.0
+  Compose and Compose Multiplatform expert for UI development across Android, Desktop,
+  iOS, and Web. Use whenever the user mentions Compose APIs (@Composable, remember,
+  LaunchedEffect, NavHost, MaterialTheme, LazyColumn, Modifier, recomposition),
+  Compose Multiplatform (commonMain, expect/actual, Res.*, ComposeUIViewController,
+  UIKitView, ComposeViewport), Android TV (tv-material, D-pad, focus, Carousel),
+  Material 3 motion, atomic design systems, design-to-code workflows, Paging 3, or
+  navigation. Activates Review Mode on GitHub PR URLs and review phrases ("review
+  this PR", "what's wrong with this"). Auto-detects Compose projects on
+  session_start. Backed by actual androidx/androidx and JetBrains/compose-multiplatform-core
+  source receipts. See "## When this skill applies" in SKILL.md for the full trigger
+  surface.
+version: 2.3.1
 ---
 
 > **Installation notice:** This skill is now distributed as a plugin.
@@ -34,6 +25,57 @@ version: 2.3.0
 > See [MIGRATION.md](../docs/MIGRATION.md) for Codex and Copilot CLI instructions.
 > This banner will remain through v2.x and escalate in v3.0.
 
+## When this skill applies
+
+The frontmatter `description:` is intentionally short to satisfy Codex / Copilot
+CLI's 1024-character cap on that field (see issue #12). The full trigger surface
+lives here so it stays available to Claude after the skill loads.
+
+### Compose API mentions
+`@Composable`, `remember`, `mutableStateOf`, `derivedStateOf`, `rememberSaveable`,
+`LaunchedEffect`, `DisposableEffect`, `SideEffect`, `rememberCoroutineScope`,
+`Scaffold`, `NavHost`, `NavController`, `MaterialTheme`, `ColorScheme`,
+`Typography`, `LazyColumn`, `LazyRow`, `LazyVerticalGrid`, `HorizontalPager`,
+`Modifier`, `Modifier.Node`, `recomposition`, `CompositionLocal`, `Style`,
+`styleable`, `MutableStyleState`.
+
+### Compose Multiplatform / KMP
+`Compose Multiplatform`, `CMP`, `KMP`, `commonMain`, `expect`, `actual`,
+`ComposeUIViewController`, `Window` composable, `UIKitView`, `ComposeViewport`,
+`Res.drawable`, `Res.string`, `SkikoMain`.
+
+### Android TV
+`tv-material`, `tv-foundation`, `Carousel`, `NavigationDrawer` (TV),
+`D-pad`, `focus indication`, `FocusRequester` on TV, `10-foot UI`,
+`living room`, `tv compose`, `Android TV`, `Google TV`, `leanback migration`.
+
+### Paging 3
+`PagingSource`, `Pager`, `PagingConfig`, `PagingData`, `LazyPagingItems`,
+`collectAsLazyPagingItems`, `RemoteMediator`, `LoadState`,
+`asSnapshot`, `TestPager`, `cachedIn`.
+
+### Design system / design-to-code
+`atomic design`, `atoms`, `molecules`, `organisms`, `templates`,
+`design tokens`, `design system`, `component library`, `reusable component`,
+`Figma to Compose`, `design to compose`, `build this UI`, `implement this design`,
+`spec to code`, `redline`.
+
+### Casual phrasing
+"my compose screen is slow", "my recomposition is broken",
+"how do I pass data between screens", "how do I build a TV app",
+"Android UI", "Kotlin UI", "compose layout", "compose navigation",
+"compose animation", "compose styles", "desktop compose", "iOS compose",
+"compose web".
+
+### Review Mode triggers
+Any GitHub PR URL matching `github.com/.*/pull/\d+`, or phrases:
+"review this PR", "review this diff", "review this code",
+"check this code", "check this diff", "what's wrong with this".
+On match, follow `references/pr-review.md` exclusively.
+
+### Session start
+Auto-detect Compose projects on `session_start` — see `references/auto-init.md`.
+
 ## Quick Routing
 
 Use this table first. Match the user's signal to one reference file and read it before