diff --git a/home/.chezmoitemplates/lib/common/install-prelude.sh b/home/.chezmoitemplates/lib/common/install-prelude.sh
index 692c3c0..a51f025 100644
--- a/home/.chezmoitemplates/lib/common/install-prelude.sh
+++ b/home/.chezmoitemplates/lib/common/install-prelude.sh
@@ -8,8 +8,12 @@
 #   scripts via chezmoi template rendering, after lib/common/log.sh and before
 #   the install library.
 #
-#   Error-handling convention:
+#   Error-handling conventions for install libraries:
 #     Missing prerequisite tool: call require_command and return on failure.
+#     Per-item install loop: keep going on failure, then warn with a summary.
+#     Single critical command: let it fail the script.
+#     Standalone run: the self-exec guard sources log.sh and this prelude when
+#                     they are not already defined.
 
 if [ "${DOTFILES_DEBUG:-}" ]; then
   set -x
diff --git a/home/.chezmoitemplates/lib/install/apm.sh b/home/.chezmoitemplates/lib/install/apm.sh
index fed3c3b..6e9de0e 100644
--- a/home/.chezmoitemplates/lib/install/apm.sh
+++ b/home/.chezmoitemplates/lib/install/apm.sh
@@ -12,6 +12,8 @@ set -Eeuo pipefail
 # @description Install APM dependencies from `${HOME}/.apm/apm.yml`.
 #
 function apm_install_main() {
+  require_command apm "Ensure run_onchange_03_install-mise-tools ran successfully." || return 1
+
   log_info "[apm] Installing globally from ~/.apm/apm.yml (frozen)..."
   cd "${HOME}/.apm" || {
     log_error "[apm] ~/.apm not found; run 'chezmoi apply' to materialize it."
@@ -31,5 +33,11 @@ function main() {
 }
 
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+  # When run directly, pull in the shared libraries that chezmoi otherwise
+  # concatenates ahead of this file.
+  # shellcheck source=/dev/null
+  command -v log_info >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/log.sh"
+  # shellcheck source=/dev/null
+  command -v require_command >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/install-prelude.sh"
   main
 fi
diff --git a/home/.chezmoitemplates/lib/install/graphify-skills.sh b/home/.chezmoitemplates/lib/install/graphify-skills.sh
index 9786f69..8c69a00 100644
--- a/home/.chezmoitemplates/lib/install/graphify-skills.sh
+++ b/home/.chezmoitemplates/lib/install/graphify-skills.sh
@@ -14,6 +14,7 @@ set -Eeuo pipefail
 function graphify_skills_install_main() {
   local has_platform=0
   local platform
+  local failed=()
 
   for platform in "${GRAPHIFY_PLATFORMS[@]-}"; do
     [[ -z "${platform}" ]] && continue
@@ -32,9 +33,17 @@ function graphify_skills_install_main() {
 
   for platform in "${GRAPHIFY_PLATFORMS[@]-}"; do
     [[ -z "${platform}" ]] && continue
-    graphify install --platform "${platform}"
+
+    if ! graphify install --platform "${platform}"; then
+      failed+=("${platform}")
+    fi
   done
 
+  if ((${#failed[@]} > 0)); then
+    log_warn "[graphify] ${#failed[@]} platform(s) failed to install:"
+    printf '  - %s\n' "${failed[@]}" >&2
+  fi
+
   log_info "[graphify] Graphify agent skills installed."
 }
 
@@ -46,5 +55,11 @@ function main() {
 }
 
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+  # When run directly, pull in the shared libraries that chezmoi otherwise
+  # concatenates ahead of this file.
+  # shellcheck source=/dev/null
+  command -v log_info >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/log.sh"
+  # shellcheck source=/dev/null
+  command -v require_command >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/install-prelude.sh"
   main
 fi
diff --git a/home/.chezmoitemplates/lib/install/homebrew-bundle.sh b/home/.chezmoitemplates/lib/install/homebrew-bundle.sh
index bfbf39c..b086728 100644
--- a/home/.chezmoitemplates/lib/install/homebrew-bundle.sh
+++ b/home/.chezmoitemplates/lib/install/homebrew-bundle.sh
@@ -30,5 +30,11 @@ function main() {
 }
 
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+  # When run directly, pull in the shared libraries that chezmoi otherwise
+  # concatenates ahead of this file.
+  # shellcheck source=/dev/null
+  command -v log_info >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/log.sh"
+  # shellcheck source=/dev/null
+  command -v require_command >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/install-prelude.sh"
   main
 fi
diff --git a/home/.chezmoitemplates/lib/install/homebrew.sh b/home/.chezmoitemplates/lib/install/homebrew.sh
index 184180d..164c972 100644
--- a/home/.chezmoitemplates/lib/install/homebrew.sh
+++ b/home/.chezmoitemplates/lib/install/homebrew.sh
@@ -53,5 +53,9 @@ function main() {
 }
 
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+  # When run directly, pull in the log library that chezmoi otherwise
+  # concatenates ahead of this file.
+  # shellcheck source=/dev/null
+  command -v log_info >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/log.sh"
   main
 fi
diff --git a/home/.chezmoitemplates/lib/install/mise.sh b/home/.chezmoitemplates/lib/install/mise.sh
index e6e9618..d6354f6 100644
--- a/home/.chezmoitemplates/lib/install/mise.sh
+++ b/home/.chezmoitemplates/lib/install/mise.sh
@@ -27,5 +27,11 @@ function main() {
 }
 
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+  # When run directly, pull in the shared libraries that chezmoi otherwise
+  # concatenates ahead of this file.
+  # shellcheck source=/dev/null
+  command -v log_info >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/log.sh"
+  # shellcheck source=/dev/null
+  command -v require_command >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/install-prelude.sh"
   main
 fi
diff --git a/home/.chezmoitemplates/lib/install/opencode-agent-tools.sh b/home/.chezmoitemplates/lib/install/opencode-agent-tools.sh
index 1a52cfa..9216563 100644
--- a/home/.chezmoitemplates/lib/install/opencode-agent-tools.sh
+++ b/home/.chezmoitemplates/lib/install/opencode-agent-tools.sh
@@ -106,5 +106,9 @@ function main() {
 }
 
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+  # When run directly, pull in the log library that chezmoi otherwise
+  # concatenates ahead of this file.
+  # shellcheck source=/dev/null
+  command -v log_info >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/log.sh"
   main
 fi
diff --git a/home/.chezmoitemplates/lib/install/uv-tools.sh b/home/.chezmoitemplates/lib/install/uv-tools.sh
index 262f482..b1ca97f 100644
--- a/home/.chezmoitemplates/lib/install/uv-tools.sh
+++ b/home/.chezmoitemplates/lib/install/uv-tools.sh
@@ -14,12 +14,21 @@ set -Eeuo pipefail
 function uv_tools_install_main() {
   log_info "[uv] Installing uv tools..."
 
+  local failed=()
   local tool
   for tool in "${UV_TOOLS[@]-}"; do
     [[ -z "${tool}" ]] && continue
-    uv tool install --upgrade "${tool}"
+
+    if ! uv tool install --upgrade "${tool}"; then
+      failed+=("${tool}")
+    fi
   done
 
+  if ((${#failed[@]} > 0)); then
+    log_warn "[uv] ${#failed[@]} tool(s) failed to install:"
+    printf '  - %s\n' "${failed[@]}" >&2
+  fi
+
   log_info "[uv] uv tools installed."
 }
 
@@ -33,5 +42,11 @@ function main() {
 }
 
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+  # When run directly, pull in the shared libraries that chezmoi otherwise
+  # concatenates ahead of this file.
+  # shellcheck source=/dev/null
+  command -v log_info >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/log.sh"
+  # shellcheck source=/dev/null
+  command -v require_command >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/install-prelude.sh"
   main
 fi
diff --git a/home/.chezmoitemplates/lib/install/vscode.sh b/home/.chezmoitemplates/lib/install/vscode.sh
index 582db2c..ec10482 100644
--- a/home/.chezmoitemplates/lib/install/vscode.sh
+++ b/home/.chezmoitemplates/lib/install/vscode.sh
@@ -8,21 +8,11 @@
 
 set -Eeuo pipefail
 
-#
-# @description Check if the VS Code CLI is installed.
-#
-function is_vscode_cli_installed() {
-  command -v code >/dev/null 2>&1
-}
-
 #
 # @description Install configured VS Code extensions.
 #
 function vscode_install_extensions_main() {
-  if ! is_vscode_cli_installed; then
-    log_warn "[vscode] VS Code CLI not found. Open VS Code and run: Shell Command: Install 'code' command in PATH"
-    return 0
-  fi
+  require_command code "Open VS Code and run: Shell Command: Install 'code' command in PATH" || return 1
 
   log_info "[vscode] Installing VS Code extensions..."
 
@@ -52,5 +42,11 @@ function main() {
 }
 
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+  # When run directly, pull in the shared libraries that chezmoi otherwise
+  # concatenates ahead of this file.
+  # shellcheck source=/dev/null
+  command -v log_info >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/log.sh"
+  # shellcheck source=/dev/null
+  command -v require_command >/dev/null 2>&1 || source "$(dirname "${BASH_SOURCE[0]}")/../common/install-prelude.sh"
   main
 fi
diff --git a/tests/unit/lib/install/apm.bats b/tests/unit/lib/install/apm.bats
index 7ebfa85..af90969 100644
--- a/tests/unit/lib/install/apm.bats
+++ b/tests/unit/lib/install/apm.bats
@@ -5,6 +5,7 @@
 load '../../../test_helpers/load.bash'
 
 LOG_LIB="$DOTFILES_ROOT/home/.chezmoitemplates/lib/common/log.sh"
+PRELUDE="$DOTFILES_ROOT/home/.chezmoitemplates/lib/common/install-prelude.sh"
 APM_LIB="$DOTFILES_ROOT/home/.chezmoitemplates/lib/install/apm.sh"
 
 setup() {
@@ -24,7 +25,7 @@ APM
 }
 
 @test "apm_install_main: runs apm install globally from ~/.apm" {
-  run bash -c "source '$LOG_LIB' && source '$APM_LIB' && apm_install_main"
+  run bash -c "source '$LOG_LIB' && source '$PRELUDE' && source '$APM_LIB' && apm_install_main"
 
   assert_success
   assert_line "[apm] Installing globally from ~/.apm/apm.yml (frozen)..."
@@ -36,7 +37,7 @@ APM
 @test "apm_install_main: warns and completes when apm install fails" {
   export APM_EXIT_CODE=7
 
-  run bash -c "source '$LOG_LIB' && source '$APM_LIB' && apm_install_main"
+  run bash -c "source '$LOG_LIB' && source '$PRELUDE' && source '$APM_LIB' && apm_install_main"
 
   assert_success
   assert_line --partial "warn: [apm] apm install --frozen exited non-zero"
diff --git a/tests/unit/lib/install/graphify-skills.bats b/tests/unit/lib/install/graphify-skills.bats
index 57877ec..1c5ddc1 100644
--- a/tests/unit/lib/install/graphify-skills.bats
+++ b/tests/unit/lib/install/graphify-skills.bats
@@ -47,6 +47,17 @@ GRAPHIFY
   [ ! -s "$GRAPHIFY_ARGS_FILE" ]
 }
 
+@test "main: warns but succeeds when a platform fails" {
+  export GRAPHIFY_EXIT_CODE=5
+
+  run bash -c "source '$LOG_LIB' && source '$PRELUDE' && source '$LIB' && GRAPHIFY_PLATFORMS=('agents') && main"
+
+  assert_success
+  assert_line "warn: [graphify] 1 platform(s) failed to install:"
+  assert_line "  - agents"
+  assert_line "[graphify] Graphify agent skills installed."
+}
+
 @test "main: fails when graphify is missing" {
   rm -f "$BATS_TEST_TMPDIR/bin/graphify"
 
diff --git a/tests/unit/lib/install/uv-tools.bats b/tests/unit/lib/install/uv-tools.bats
index 04f8650..a03ec7b 100644
--- a/tests/unit/lib/install/uv-tools.bats
+++ b/tests/unit/lib/install/uv-tools.bats
@@ -38,12 +38,15 @@ UV
   [ "$(<"$UV_ARGS_FILE")" = $'tool install --upgrade graphifyy\ntool install --upgrade tavily-cli' ]
 }
 
-@test "uv_tools_install_main: fails when uv tool install fails" {
+@test "uv_tools_install_main: warns but succeeds when a tool fails" {
   export UV_FAIL_TOOL='tavily-cli'
 
   run bash -c "source '$LOG_LIB' && source '$LIB' && UV_TOOLS=('graphifyy' 'tavily-cli') && uv_tools_install_main"
 
-  assert_failure 8
+  assert_success
   assert_line "[uv] Installing uv tools..."
+  assert_line "warn: [uv] 1 tool(s) failed to install:"
+  assert_line "  - tavily-cli"
+  assert_line "[uv] uv tools installed."
   [ "$(<"$UV_ARGS_FILE")" = $'tool install --upgrade graphifyy\ntool install --upgrade tavily-cli' ]
 }
diff --git a/tests/unit/lib/install/vscode.bats b/tests/unit/lib/install/vscode.bats
index db87e46..dffd7bc 100644
--- a/tests/unit/lib/install/vscode.bats
+++ b/tests/unit/lib/install/vscode.bats
@@ -5,6 +5,7 @@
 load '../../../test_helpers/load.bash'
 
 LOG_LIB="$DOTFILES_ROOT/home/.chezmoitemplates/lib/common/log.sh"
+PRELUDE="$DOTFILES_ROOT/home/.chezmoitemplates/lib/common/install-prelude.sh"
 LIB="$DOTFILES_ROOT/home/.chezmoitemplates/lib/install/vscode.sh"
 
 setup() {
@@ -23,7 +24,7 @@ CODE
 }
 
 @test "vscode_install_extensions_main: installs each extension with force" {
-  run bash -c "source '$LOG_LIB' && source '$LIB' && VSCODE_EXTENSIONS=('one.ext' 'two.ext') && vscode_install_extensions_main"
+  run bash -c "source '$LOG_LIB' && source '$PRELUDE' && source '$LIB' && VSCODE_EXTENSIONS=('one.ext' 'two.ext') && vscode_install_extensions_main"
 
   assert_success
   assert_line "[vscode] Installing VS Code extensions..."
@@ -34,10 +35,20 @@ CODE
 @test "vscode_install_extensions_main: warns but succeeds when an extension fails" {
   export CODE_FAIL_EXTENSION='bad.ext'
 
-  run bash -c "source '$LOG_LIB' && source '$LIB' && VSCODE_EXTENSIONS=('good.ext' 'bad.ext') && vscode_install_extensions_main"
+  run bash -c "source '$LOG_LIB' && source '$PRELUDE' && source '$LIB' && VSCODE_EXTENSIONS=('good.ext' 'bad.ext') && vscode_install_extensions_main"
 
   assert_success
   assert_line "warn: [vscode] 1 extension(s) failed to install:"
   assert_line "  - bad.ext"
   assert_line "[vscode] VS Code extensions installed."
 }
+
+@test "vscode_install_extensions_main: fails when the VS Code CLI is missing" {
+  rm -f "$BATS_TEST_TMPDIR/bin/code"
+  export PATH="$BATS_TEST_TMPDIR/bin:/usr/bin:/bin"
+
+  run bash -c "source '$LOG_LIB' && source '$PRELUDE' && source '$LIB' && VSCODE_EXTENSIONS=('one.ext') && vscode_install_extensions_main"
+
+  assert_failure 1
+  assert_line "error: [code] not found. Open VS Code and run: Shell Command: Install 'code' command in PATH"
+}