align skills with additive project policy

AGENTS.md

@@ -5,15 +5,16 @@
 ## Layout
 
 - `skills/<name>/SKILL.md` — one narrowly triggered on-demand behavior.
-- `bin/ink-skills` — dependency-free installer; stdout is TSV, diagnostics stderr.
+- `bin/ink-skills` — POSIX linker/importer; stdout is TSV, diagnostics stderr.
 - `test/install-smoke.sh` — installer contract smoke.
 
 ## Rules
 
 - A skill owns reusable judgment, never runtime policy or repeatable mechanics.
-- Ink source and `REQUIREMENTS.md` own host behavior; `toolset` owns external executables.
+- Ink source and `SPEC.md` own host behavior; `toolset` owns external executables.
 - Keep skill names lowercase and hyphenated; directory and frontmatter name must match.
-- The installer only creates symlinks and must refuse collisions. Do not add a registry,
+- `link` only creates symlinks. `import` may materialize only a caller-supplied,
-  network calls, package-manager dependency, prompts, copies, or hidden state.
+  SHA-256-verified local archive in the content-addressed store. Do not add URL,
+  Git, credential, registry, package-manager, prompt, or updater behavior.
 - Run `sh -n bin/ink-skills`, `sh test/install-smoke.sh`, and
   `sh test/skills-smoke.sh` after changes.

README.md

@@ -7,61 +7,58 @@ This repository owns reusable Ink judgment. Ink owns runtime enforcement and
 policy. [`toolset`](https://git.tmk241.com/tmk241/toolset) owns compiled external
 executables. Skills never grant authority by themselves.
 
-## Install
+## Link local skills
 
-Clone once, then symlink the skills you want:
+Clone once, then link every skill shipped by this checkout:
 
 ```sh
 git clone git@git.tmk241.com:tmk241/ink-skills.git
-ink-skills/bin/ink-skills install
+ink-skills/bin/ink-skills link
 ```
 
-If the repository is already under `/opt/repositories`:
+Link selected directories or target one project:
 
 ```sh
-/opt/repositories/ink-skills/bin/ink-skills install
+ink-skills link /opt/repositories/ink-skills/skills/audit-ink-cli
+ink-skills link --project /path/to/project skills/configure-ink-agent
 ```
 
-Install selected skills only:
+`link` only creates absolute symlinks. It performs no network access, copies,
+prompts, registry lookup, or policy mutation. Pulling a linked checkout changes
+its bytes; restart Ink to freeze the updated skill snapshot.
+
+## Import verified artifacts
+
+Transport and authentication remain ordinary shell jobs:
 
 ```sh
-ink-skills install audit-ink-cli configure-ink-agent
+curl -fLo skills.tar https://example/skills.tar
+git archive --format=tar HEAD >skills.tar
 ```
 
-Install into one project instead of the user catalogue:
+The publisher communicates the expected digest out of band. Import only after you
+have that value:
 
 ```sh
-ink-skills install --project /path/to/project configure-ink-agent
+ink-skills import sha256:012345... skills.tar
+ink-skills import --project /path/to/project sha256:012345... skills.tar skills/review-sql
 ```
 
-Install from any Git repository your normal Git credentials can read:
+`import` verifies the complete archive before extraction, accepts only regular
+files and directories with safe relative paths, and rejects symlinks and special
+files. It materializes the tree under
+`$INK_SKILLS_STORE/sha256/HASH` (or the XDG/default data path), then links skills
+from that immutable content-addressed location. `.ink-skills.tsv` records each
+installed skill's archive digest and path without modifying `SKILL.md`.
 
-```sh
+The same artifact works whether it arrived via curl, scp, USB, a browser download,
-ink-skills add --ref main git@git.example:team/skills.git
+or `git archive`. `ink-skills` deliberately has no URL, Git, credential, branch,
-ink-skills add https://git.example/team/skills.git skills/review-sql
+release, or update logic.
-```
 
-`add` resolves the ref to one commit, exports it into a content-addressed store,
+Ink discovers `$HOME/.ink/skills`, `$CWD/.ink/skills`, and colon-separated
-computes a SHA-256 over each selected skill tree, and symlinks that immutable
+`INK_SKILLS_DIRS`. The installer-only `$INK_SKILLS_HOME` overrides the user link
-artifact. Provenance is recorded next to installed links in `.ink-skills.tsv`:
+target. `ink-skills list` emits TSV; `ink-skills --help` is the complete command
-source, requested ref, resolved commit, path, and SHA-256. It deliberately does
+manual. Existing paths and foreign symlinks are refused rather than overwritten.
-not edit `SKILL.md` comments. A moved branch does not silently update an installed
-skill; the existing pin causes a visible provenance collision.
-
-Git SSH agents and credential helpers remain Git's job. Credential-bearing HTTP
-URLs are refused so secrets do not enter manifests or process listings. Remote
-skill trees containing symlinks are also refused.
-
-The local `install` path is intentionally smaller than `npx skills`: no registry,
-package manager, network access, copies, prompts, lockfile, or hidden state. It
-creates absolute symlinks from `$HOME/.ink/skills` (or the installer-only
-`$INK_SKILLS_HOME` target override) to this checkout. Pulling the repository
-updates locally installed skills; restarting Ink freezes the new bytes into the
-next startup snapshot. Ink itself discovers `$HOME/.ink/skills`,
-`$CWD/.ink/skills`, and colon-separated `INK_SKILLS_DIRS`.
-
-`ink-skills list` emits TSV. `ink-skills --help` is the complete command manual.
-Existing paths and foreign symlinks are refused rather than overwritten.
 
 ## Skills
 
@@ -88,6 +85,12 @@ Implement the bounded frontend task and return proof.
 `access: read|write` selects reader/writer scheduling; it does not grant commands
 or tools. Definitions are frozen at startup, so restart Ink after changing one.
 
+Approved rows from `$HOME/.ink/policy` and ancestor project `.ink/policy` files are
+additive alternatives. A project file can introduce a command only through the
+normalized effective-policy digest approval; it is never trusted merely because it
+exists. Empty project policy adds nothing. Child/session policy and the immutable
+host floor may only narrow the approved durable rows.
+
 Current caveat: Ink records `policy:` as frozen metadata but does not yet read the
 named relative file into the child effective policy. Do not treat it as enforced.
 Use the `configure-ink-agent` skill for the exact boundary and blocker.

bin/ink-skills

@@ -4,41 +4,41 @@ set -eu
 usage() {
     cat <<'EOF'
 usage: ink-skills list
-       ink-skills install [--user | --project DIR] [SKILL ...]
+       ink-skills link [--user | --project DIR] [SKILL_DIR ...]
-       ink-skills add [--user | --project DIR] [--ref REF] REPOSITORY [PATH ...]
+       ink-skills import [--user | --project DIR] sha256:HASH ARCHIVE [PATH ...]
 
-Install Ink skills as symlinks from this checkout or a pinned Git artifact.
+Link local Ink skills or import a verified skill archive.
 
 Commands:
-  list             List skills in this checkout as TSV.
+  list      List skills shipped by this checkout as TSV.
-  install          Link named local skills; with no names, link every skill.
+  link      Symlink local skill directories. With no directories, link every
-  add              Fetch REPOSITORY, pin REF to a commit, materialize an
+            skill shipped by this checkout.
-                   immutable snapshot, and link skill PATHs from it. PATH
+  import    Verify ARCHIVE against the required SHA-256, safely materialize its
-                   defaults to every skills/*/SKILL.md directory.
+            immutable tree, then link selected skill PATHs. PATH defaults to
+            every skills/*/SKILL.md directory in the archive.
 
 Targets:
   --user           $INK_SKILLS_HOME or $HOME/.ink/skills (default)
   --project DIR    DIR/.ink/skills
 
-Git storage:
+Artifact store:
   $INK_SKILLS_STORE or $XDG_DATA_HOME/ink-skills, otherwise
-  $HOME/.local/share/ink-skills. Git, tar, and sha256sum are required by `add`.
+  $HOME/.local/share/ink-skills.
-  Authentication belongs to Git's SSH agent or credential helper; credentialed
+
-  HTTP URLs are refused. Installed provenance is written to
+Transport is deliberately external:
-  TARGET/.ink-skills.tsv without modifying SKILL.md.
+  curl -fLo skills.tar URL
+  ink-skills import sha256:HASH skills.tar
 
 Output:
-  TSV with SKILL, TARGET, ACTION, SOURCE, COMMIT, and SHA256 columns.
+  TSV with SKILL, TARGET, ACTION, SOURCE, and SHA256 columns.
 
 Exit status:
-  0 success; 2 usage error; 3 collision, invalid source, or fetch failure.
+  0 success; 2 usage error; 3 invalid skill, collision, digest mismatch, or
+  unsafe archive.
 
-Examples:
+Requirements:
-  ink-skills list
+  POSIX sh and standard text tools. `import` additionally needs tar and one of
-  ink-skills install audit-ink-cli configure-ink-agent
+  sha256sum, shasum, or openssl.
-  ink-skills install --project . create-ink-tool
-  ink-skills add --ref main git@git.example:team/skills.git
-  ink-skills add https://git.example/team/skills.git skills/review-sql
 EOF
 }
 
@@ -47,6 +47,22 @@ die() {
     exit 3
 }
 
+script_dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd -P)
+repo_dir=$(CDPATH= cd -- "$script_dir/.." && pwd -P)
+bundled_dir=$repo_dir/skills
+cleanup_root=
+cleanup_artifact=
+cleanup_lock=
+cleanup_all() {
+    if [ -n "$cleanup_artifact" ]; then
+        chmod -R u+w "$cleanup_artifact" 2>/dev/null || :
+        rm -rf "$cleanup_artifact"
+    fi
+    [ -z "$cleanup_lock" ] || rmdir "$cleanup_lock" 2>/dev/null || :
+    [ -z "$cleanup_root" ] || rm -rf "$cleanup_root"
+}
+trap cleanup_all EXIT HUP INT TERM
+
 reject_record_breaks() {
     case $1 in
         *"	"*|*"
@@ -54,17 +70,20 @@ reject_record_breaks() {
     esac
 }
 
-script_dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd -P)
+frontmatter_name() {
-repo_dir=$(CDPATH= cd -- "$script_dir/.." && pwd -P)
+    sed -n 's/^name:[[:space:]]*//p' "$1/SKILL.md" | sed -n '1p'
-skills_dir=$repo_dir/skills
+}
 
-list_skills() {
+validate_skill_dir() {
-    printf 'SKILL\tSOURCE\n'
+    skill_dir=$1
-    for path in "$skills_dir"/*; do
+    [ -d "$skill_dir" ] && [ -f "$skill_dir/SKILL.md" ] || die "not a skill directory: $skill_dir"
-        [ -d "$path" ] || continue
+    [ ! -L "$skill_dir" ] && [ ! -L "$skill_dir/SKILL.md" ] || die "skill root and SKILL.md must not be symlinks: $skill_dir"
-        [ -f "$path/SKILL.md" ] || continue
+    skill_name=$(frontmatter_name "$skill_dir")
-        printf '%s\t%s\n' "$(basename -- "$path")" "$path"
+    [ -n "$skill_name" ] || die "missing frontmatter name: $skill_dir/SKILL.md"
-    done
+    [ "$skill_name" = "$(basename -- "$skill_dir")" ] || die "frontmatter name does not match directory: $skill_dir"
+    case $skill_name in
+        ''|.*|*/*) die "invalid skill name: $skill_name" ;;
+    esac
 }
 
 select_target() {
@@ -85,11 +104,12 @@ select_target() {
     mkdir -p -- "$target"
 }
 
-parse_target_option() {
+parse_target_options() {
+    while [ "$#" -gt 0 ]; do
         case $1 in
             --user)
                 target_mode=user
-            shift_count=1
+                shift
                 ;;
             --project)
                 [ "$#" -ge 2 ] || {
@@ -98,35 +118,34 @@ parse_target_option() {
                 }
                 target_mode=project
                 target_arg=$2
-            shift_count=2
+                shift 2
                 ;;
-        *) shift_count=0 ;;
+            --)
-    esac
+                shift
-}
+                break
-
+                ;;
-frontmatter_name() {
+            -*)
-    sed -n 's/^name:[[:space:]]*//p' "$1/SKILL.md" | sed -n '1p'
+                usage >&2
-}
+                exit 2
-
+                ;;
-validate_skill_dir() {
+            *) break ;;
-    source_path=$1
-    [ -d "$source_path" ] && [ -f "$source_path/SKILL.md" ] || die "not a skill directory: $source_path"
-    [ ! -L "$source_path" ] && [ ! -L "$source_path/SKILL.md" ] || die "skill root and SKILL.md must not be symlinks: $source_path"
-    skill_name=$(frontmatter_name "$source_path")
-    [ -n "$skill_name" ] || die "missing frontmatter name: $source_path/SKILL.md"
-    [ "$skill_name" = "$(basename -- "$source_path")" ] || die "frontmatter name does not match directory: $source_path"
-    case $skill_name in
-        ''|.*|*/*) die "invalid skill name: $skill_name" ;;
         esac
+    done
+    remaining_count=$#
+    remaining_file=$work_args
+    : >"$remaining_file"
+    for arg do
+        reject_record_breaks "$arg"
+        printf '%s\n' "$arg" >>"$remaining_file"
+    done
 }
 
 link_skill() {
-    skill_name=$1
+    name=$1
     source_path=$2
     source_label=$3
-    commit=$4
+    digest=$4
-    digest=$5
+    destination=$target/$name
-    destination=$target/$skill_name
     if [ -L "$destination" ]; then
         linked=$(readlink "$destination")
         [ "$linked" = "$source_path" ] || die "refusing foreign symlink: $destination -> $linked"
@@ -137,34 +156,58 @@ link_skill() {
         ln -s -- "$source_path" "$destination"
         action=linked
     fi
-    printf '%s\t%s\t%s\t%s\t%s\t%s\n' "$skill_name" "$destination" "$action" "$source_label" "$commit" "$digest"
+    printf '%s\t%s\t%s\t%s\t%s\n' "$name" "$destination" "$action" "$source_label" "$digest"
 }
 
-check_source_record() {
+manifest_check() {
-    skill_name=$1
+    name=$1
-    source_label=$2
+    digest=$2
-    ref=$3
+    archive_path=$3
-    commit=$4
-    skill_path=$5
-    digest=$6
     manifest=$target/.ink-skills.tsv
     record_needed=yes
-    [ -e "$manifest" ] || return 0
+    [ -f "$manifest" ] || return 0
-    if awk -F '\t' -v skill="$skill_name" 'NR > 1 && $1 == skill { found = 1 } END { exit !found }' "$manifest"; then
+    if awk -F '\t' -v name="$name" 'NR > 1 && $1 == name { found = 1 } END { exit !found }' "$manifest"; then
-        existing=$(awk -F '\t' -v skill="$skill_name" 'NR > 1 && $1 == skill { print $0; exit }' "$manifest")
+        existing=$(awk -F '\t' -v name="$name" 'NR > 1 && $1 == name { print $0; exit }' "$manifest")
-        wanted=$(printf '%s\t%s\t%s\t%s\t%s\t%s' "$skill_name" "$source_label" "$ref" "$commit" "$skill_path" "$digest")
+        wanted=$(printf '%s\t%s\t%s' "$name" "$digest" "$archive_path")
-        [ "$existing" = "$wanted" ] || die "provenance collision for installed skill: $skill_name"
+        [ "$existing" = "$wanted" ] || die "provenance collision for installed skill: $name"
         record_needed=no
     fi
 }
 
-append_source_record() {
+manifest_append() {
     [ "$record_needed" = yes ] || return 0
     manifest=$target/.ink-skills.tsv
-    if [ ! -e "$manifest" ]; then
+    [ -e "$manifest" ] || printf 'SKILL\tSHA256\tPATH\n' >"$manifest"
-        printf 'SKILL\tSOURCE\tREF\tCOMMIT\tPATH\tSHA256\n' >"$manifest"
+    printf '%s\t%s\t%s\n' "$name" "$digest" "$archive_path" >>"$manifest"
+}
+
+sha256_file() {
+    file=$1
+    if command -v sha256sum >/dev/null 2>&1; then
+        sha256sum "$file" | awk '{print $1}'
+    elif command -v shasum >/dev/null 2>&1; then
+        shasum -a 256 "$file" | awk '{print $1}'
+    elif command -v openssl >/dev/null 2>&1; then
+        openssl dgst -sha256 "$file" | sed 's/^.*= //'
+    else
+        die 'import requires sha256sum, shasum, or openssl'
     fi
-    printf '%s\t%s\t%s\t%s\t%s\t%s\n' "$skill_name" "$repository" "$ref" "$commit" "$skill_path" "$digest" >>"$manifest"
+}
+
+validate_archive_listing() {
+    archive=$1
+    names=$2
+    types=$3
+    tar -tf "$archive" >"$names" || die "cannot list archive: $archive"
+    [ -s "$names" ] || die 'archive is empty'
+    while IFS= read -r member; do
+        reject_record_breaks "$member"
+        case $member in
+            ''|/*|..|../*|*/../*|*/..) die "unsafe archive path: $member" ;;
+        esac
+    done <"$names"
+    LC_ALL=C tar -tvf "$archive" >"$types" || die "cannot inspect archive: $archive"
+    awk 'substr($1, 1, 1) != "-" && substr($1, 1, 1) != "d" { exit 1 }' "$types" || die 'archive may contain only regular files and directories'
 }
 
 [ "$#" -gt 0 ] || {
@@ -183,10 +226,14 @@ case $command in
             usage >&2
             exit 2
         }
-        list_skills
+        printf 'SKILL\tSOURCE\n'
+        for path in "$bundled_dir"/*; do
+            [ -d "$path" ] && [ -f "$path/SKILL.md" ] || continue
+            printf '%s\t%s\n' "$(basename -- "$path")" "$path"
+        done
         exit 0
         ;;
-    install|add) ;;
+    link|import) ;;
     *)
         usage >&2
         exit 2
@@ -195,74 +242,57 @@ esac
 
 target_mode=user
 target_arg=
-ref=HEAD
+work_root=${TMPDIR:-/tmp}/ink-skills-args-$$
-while [ "$#" -gt 0 ]; do
+(umask 077 && mkdir "$work_root") || die "cannot create temporary directory: $work_root"
-    parse_target_option "$@"
+cleanup_root=$work_root
-    if [ "$shift_count" -gt 0 ]; then
+work_args=$work_root/args
-        shift "$shift_count"
+parse_target_options "$@"
-        continue
+set --
-    fi
+while IFS= read -r arg; do set -- "$@" "$arg"; done <"$work_args"
-    case $1 in
-        --ref)
-            [ "$command" = add ] && [ "$#" -ge 2 ] || {
-                usage >&2
-                exit 2
-            }
-            ref=$2
-            shift 2
-            ;;
-        --)
-            shift
-            break
-            ;;
-        -*)
-            usage >&2
-            exit 2
-            ;;
-        *) break ;;
-    esac
-done
 select_target
 
-printf 'SKILL\tTARGET\tACTION\tSOURCE\tCOMMIT\tSHA256\n'
+printf 'SKILL\tTARGET\tACTION\tSOURCE\tSHA256\n'
 
-if [ "$command" = install ]; then
+if [ "$command" = link ]; then
     if [ "$#" -eq 0 ]; then
         set --
-        for path in "$skills_dir"/*; do
+        for path in "$bundled_dir"/*; do
-            [ -d "$path" ] || continue
+            [ -d "$path" ] && [ -f "$path/SKILL.md" ] || continue
-            [ -f "$path/SKILL.md" ] || continue
+            set -- "$@" "$path"
-            set -- "$@" "$(basename -- "$path")"
         done
     fi
-    for skill do
+    for source_path do
-        case $skill in
+        case $source_path in
-            ''|.*|*/*) die "invalid skill name: $skill" ;;
+            /*) ;;
+            *) source_path=$(CDPATH= cd -- "$(dirname -- "$source_path")" 2>/dev/null && printf '%s/%s\n' "$PWD" "$(basename -- "$source_path")") || die "skill directory not found: $source_path" ;;
         esac
-        source_path=$skills_dir/$skill
         validate_skill_dir "$source_path"
-        link_skill "$skill_name" "$source_path" local - -
+        link_skill "$skill_name" "$source_path" local -
     done
     exit 0
 fi
 
-[ "$#" -gt 0 ] || {
+[ "$#" -ge 2 ] || {
     usage >&2
     exit 2
 }
-repository=$1
+digest_spec=$1
-shift
+archive=$2
-reject_record_breaks "$repository"
+shift 2
-reject_record_breaks "$ref"
+case $digest_spec in
-case $ref in
+    sha256:*) digest=${digest_spec#sha256:} ;;
-    -*) die "invalid ref: $ref" ;;
+    *) die 'digest must use sha256:HASH' ;;
 esac
-case $repository in
+digest=$(printf '%s' "$digest" | tr 'A-F' 'a-f')
-    http://*@*|https://*@*) die 'credentialed HTTP URLs are refused; use an SSH agent or Git credential helper' ;;
+case $digest in
+    *[!0-9a-f]*|'') die 'SHA-256 must contain 64 hexadecimal characters' ;;
 esac
-command -v git >/dev/null 2>&1 || die 'git is required by add'
+[ "${#digest}" -eq 64 ] || die 'SHA-256 must contain 64 hexadecimal characters'
-command -v tar >/dev/null 2>&1 || die 'tar is required by add'
+[ -f "$archive" ] || die "archive not found: $archive"
-command -v sha256sum >/dev/null 2>&1 || die 'sha256sum is required by add'
+command -v tar >/dev/null 2>&1 || die 'import requires tar'
+actual=$(sha256_file "$archive")
+actual=$(printf '%s' "$actual" | tr 'A-F' 'a-f')
+[ "$actual" = "$digest" ] || die "SHA-256 mismatch: expected $digest, got $actual"
 
 if [ -n "${INK_SKILLS_STORE:-}" ]; then
     store=$INK_SKILLS_STORE
@@ -272,48 +302,51 @@ else
     [ -n "${HOME:-}" ] || die 'HOME is unset; set HOME, XDG_DATA_HOME, or INK_SKILLS_STORE'
     store=$HOME/.local/share/ink-skills
 fi
-repo_key=$(printf '%s' "$repository" | git hash-object --stdin) || die 'cannot hash repository identity'
+artifact=$store/sha256/$digest
-mirror=$store/git/$repo_key.git
+tree=$artifact/tree
-mkdir -p -- "$store/git" "$store/artifacts/$repo_key"
+if [ -d "$artifact" ]; then
-if [ ! -d "$mirror" ]; then
+    [ -f "$artifact/complete" ] && [ "$(cat "$artifact/complete")" = "$digest" ] || die "incomplete artifact store entry: $artifact"
-    git clone --quiet --mirror -- "$repository" "$mirror" || die "cannot clone repository: $repository"
+else
+    mkdir -p -- "$store/sha256"
+    lock=$store/sha256/.$digest.lock
+    mkdir "$lock" 2>/dev/null || die "artifact import already in progress: $digest"
+    temporary=$store/sha256/.$digest.tmp.$$
+    cleanup_lock=$lock
+    cleanup_artifact=$temporary
+    mkdir -p -- "$temporary/tree"
+    validate_archive_listing "$archive" "$work_root/names" "$work_root/types"
+    tar -xf "$archive" -C "$temporary/tree" || die "cannot extract archive: $archive"
+    if find "$temporary/tree" -type l -print | grep . >/dev/null 2>&1; then
+        die 'archive extracted symlinks'
     fi
-git --git-dir="$mirror" fetch --quiet --force origin "$ref" || die "cannot fetch ref: $ref"
+    if find "$temporary/tree" ! -type d ! -type f -print | grep . >/dev/null 2>&1; then
-commit=$(git --git-dir="$mirror" rev-parse --verify 'FETCH_HEAD^{commit}') || die "ref does not resolve to a commit: $ref"
+        die 'archive extracted non-file entries'
-artifact=$store/artifacts/$repo_key/$commit
-if [ ! -d "$artifact" ]; then
-    temporary=$artifact.tmp.$$
-    rm -rf -- "$temporary"
-    mkdir -p -- "$temporary"
-    if ! git --git-dir="$mirror" archive "$commit" | tar -x -C "$temporary"; then
-        rm -rf -- "$temporary"
-        die "cannot materialize commit: $commit"
     fi
-    mv -- "$temporary" "$artifact"
+    printf '%s\n' "$digest" >"$temporary/complete"
+    chmod -R a-w "$temporary"
+    mv "$temporary" "$artifact"
+    cleanup_artifact=
+    rmdir "$lock"
+    cleanup_lock=
 fi
 
 if [ "$#" -eq 0 ]; then
     set --
-    for source_path in "$artifact"/skills/*; do
+    for skill_dir in "$tree"/skills/*; do
-        [ -d "$source_path" ] || continue
+        [ -d "$skill_dir" ] && [ -f "$skill_dir/SKILL.md" ] || continue
-        [ -f "$source_path/SKILL.md" ] || continue
+        set -- "$@" "skills/$(basename -- "$skill_dir")"
-        set -- "$@" "skills/$(basename -- "$source_path")"
     done
-    [ "$#" -gt 0 ] || die "repository has no skills/*/SKILL.md at $commit"
+    [ "$#" -gt 0 ] || die 'archive has no skills/*/SKILL.md directories'
 fi
 
-for skill_path do
+for archive_path do
-    reject_record_breaks "$skill_path"
+    case $archive_path in
-    case $skill_path in
+        ''|/*|*:*|..|../*|*/../*|*/..) die "invalid archive skill path: $archive_path" ;;
-        ''|/*|*:*|..|../*|*/../*|*/..) die "invalid repository skill path: $skill_path" ;;
     esac
-    source_path=$artifact/$skill_path
+    source_path=$tree/$archive_path
     validate_skill_dir "$source_path"
-    if find "$source_path" -type l -print | grep . >/dev/null 2>&1; then
+    name=$skill_name
-        die "remote skill contains symlinks: $skill_path"
+    manifest_check "$name" "$digest" "$archive_path"
-    fi
+    link_skill "$name" "$source_path" artifact "$digest"
-    digest=$(git --git-dir="$mirror" archive "$commit:$skill_path" | sha256sum | awk '{print $1}') || die "cannot hash skill artifact: $skill_path"
+    manifest_append
-    check_source_record "$skill_name" "$repository" "$ref" "$commit" "$skill_path" "$digest"
-    link_skill "$skill_name" "$source_path" "$repository" "$commit" "$digest"
-    append_source_record
 done

skills/audit-ink-cli/SKILL.md

@@ -37,14 +37,16 @@ changes belong to Ink's repository authority and implementation workflow.
 - A human/operator may invoke Ink outside the governed agent. Give a copyable
   operator command only when the user asks and its public help contract is proven.
 - Use user-provided runtime output as runtime evidence. Otherwise inspect the
-  installed artifact identity and a demonstrably matching checkout's requirements,
+  installed artifact identity and a demonstrably matching checkout's specification,
   tests, public help text, and source; label those findings as contract/source
   evidence rather than executed runtime proof.
-- Global and project policy files explain only their contribution. Effective
+- Approved global and ancestor-project rows are additive alternatives; each file
-  authority also depends on all policy layers, pinned executable and contract
+  explains only its contribution. Effective authority also depends on the approved
-  bytes, startup freezing, and session decisions.
+  normalized digest, restrictive child/session policy, the host floor, pinned
+  executable and contract bytes, startup freezing, and session decisions. Never
+  interpret a project file as automatically trusted.
 - Treat handovers, READMEs, examples, hidden source branches, and remembered argv
-  as leads. Public help owns operator-facing commands; requirements own intended
+  as leads. Public help owns operator-facing commands; the specification owns intended
   behavior; tests and source establish current checkout behavior.
 
 Distinguish three surfaces explicitly:
@@ -71,7 +73,7 @@ the frozen `tool delegate` subject.
    **source-confirmed**, **missing**, **stale claim**, or **not proven**.
 4. For an operator action, explain that the user—not the hosted agent—must run it.
    Do not inspect or mutate session state as a substitute.
-5. For a missing capability, require Ink's requirements authority before source
+5. For a missing capability, require Ink's specification authority before source
    implementation. Do not model it as a new external executable merely to bypass
    the host boundary.
 
@@ -93,7 +95,7 @@ the frozen `tool delegate` subject.
 EVIDENCE: <runtime output, installed artifact, matching source, or limitation>
 SURFACE: <operator CLI, model built-in, or admitted external command>
 FINDING: <observed/source-confirmed/missing/stale/not proven>
-ACTION: <operator step, requirements step, or none>
+ACTION: <operator step, specification step, or none>
 ```
 
 Positive smoke: “Does Ink have a sessions command, and why can’t you run it?”

skills/configure-ink-agent/SKILL.md

@@ -63,7 +63,7 @@ no ancestor-chain project-agent discovery.
 - `read` children may overlap and receive an immutable host floor with no command,
   file-mutation, lifecycle-mutation, or delegation authority.
 - `write` children are exclusive, operate in the canonical parent cwd, pause
-  parent effects, and still receive only their effective frozen policy.
+  parent mutations, and still receive only their effective frozen policy.
 
 Never infer effective authority from `access`, prompt text, or a `policy:` label.
 Use the child policy snapshot and a real allowed/denied smoke.
@@ -83,11 +83,12 @@ policy. Therefore:
   those are already sufficient.
 
 This gate may be removed only after the provider launch path proves that the
-referenced bytes are pinned and conjoined into the child effective policy.
+referenced bytes are pinned and applied as a restriction to the child's inherited
+approved durable policy.
 
 ## Decision loop
 
-1. Choose `read` unless the child must produce a real effect.
+1. Choose `read` unless the child must perform a real mutation.
 2. Choose the smallest model alias that fits the specialist job.
 3. Put the definition in user scope or exact project cwd according to intended
    precedence.
@@ -107,8 +108,8 @@ referenced bytes are pinned and conjoined into the child effective policy.
 ## Behavior smoke
 
 Positive: “Create a frontend writer child with only formatter and file mutation
-authority” loads this skill and blocks until the named policy is actually
+authority” loads this skill and blocks until the named restrictive policy is
-conjoined or the parent frozen policy already supplies that exact boundary.
+actually enforced or the parent frozen policy already supplies that exact boundary.
 
 Negative: “Ask the existing reviewer to inspect this diff” does not load this
 skill; it is ordinary delegation.

skills/create-ink-tool/SKILL.md

@@ -13,7 +13,7 @@ description: >-
 ## One job
 
 Design a **permission-sized executable** whose name and argv expose its reachable
-effects so Ink can discover, digest-pin, and grant it without granting a platform.
+reads and mutations so Ink can discover, digest-pin, and grant it without granting a platform.
 One executable need not mean one source file: share private build-time modules
 when that does not widen runtime authority.
 
@@ -21,26 +21,26 @@ when that does not widen runtime authority.
 
 Read only what can change the boundary:
 
-- the exact job and every reachable side effect;
+- the exact job and every reachable mutation;
-- Ink's current requirements, policy grammar, and mutation protocol;
+- Ink's current specification, policy grammar, and mutation protocol;
 - neighboring tools and existing executables that may already satisfy the job;
 - resource, credential, selector, target, packaging, and proof contracts;
-- repository requirements and tests.
+- repository specification and tests.
 
 Project authority outranks this skill. Missing selector semantics, credentials,
 recovery rules, or external contracts are blockers—not adapter opportunities.
 
 ```text
-JOB -> REUSE? -> EFFECTS -> BOUNDARY -> CONTRACT -> ARTIFACT -> PROOF
+JOB -> REUSE? -> READS/MUTATIONS -> BOUNDARY -> CONTRACT -> ARTIFACT -> PROOF
 ```
 
 1. Reuse a directly inspectable executable only when granting its whole reachable
    surface is honest; otherwise build the coherent missing boundary, not a wrapper.
-2. Enumerate reads, mutations, network effects, secrets, state, children, and
+2. Enumerate reads, mutations, network calls, secrets, state, children, and
    config/plugin discovery; split where approval, blast radius, or recovery differ.
 3. Define argv, selectors, streams, errors, dependencies, exhaustive versus
    bounded output, and any tool-owned semantic presentation without recreating
-   shell grammar or a host-wide effect ontology.
+   shell grammar or a host-wide mutation ontology.
 4. State the runtime artifact honestly, then falsify its boundary, behavior,
    presentation, and portability claims through Ink's real run entry point.
 
@@ -108,7 +108,7 @@ Shell globs, path filters, and content patterns are different contracts.
 
 `find`/`fd` forms that execute or delete and `rg` forms that launch preprocessors
 are not read boundaries merely because one intended invocation only searches. A
-narrow native search tool is justified when it removes reachable effects, adds
+narrow native search tool is justified when it removes reachable mutations, adds
 canonical path selectors, or supplies the required static portable artifact.
 Implement the coherent missing subset, not a compatibility facade or renamed
 wrapper.
@@ -125,8 +125,8 @@ tool apply <id> <hash>              # revalidate; perform once
 
 Required properties:
 
-- `stage` performs no external effect and resolves no secrets;
+- `stage` performs no mutation and resolves no secrets;
-- the manifest pins executable identity, canonical effect, authority subject,
+- the manifest pins executable identity, canonical mutation, authority subject,
   non-secret inputs, and drift-sensitive hashes;
 - selectors are variable semantic facts, never argv prefixes, shell text, or
   executable invariants;
@@ -149,7 +149,7 @@ layout; the tool owns meaning.
 
 Use the repository's elected projection envelope and bounds exactly; never invent
 per-tool presentation formats. Within that contract, use a small display
-vocabulary rather than universal effect kinds:
+vocabulary rather than universal mutation kinds:
 
 - headline and canonical target;
 - ordered key/value facts;
@@ -159,7 +159,7 @@ vocabulary rather than universal effect kinds:
 Filesystem, HTTP, cloud, and infrastructure tools express their own semantics
 with those primitives. For example, an HTTP mutator supplies method, canonical
 origin/path, bounded body summary, status, and final URL as facts; it does not ask
-Ink to understand an `http` effect type. An infrastructure tool supplies account,
+Ink to understand an `http` mutation type. An infrastructure tool supplies account,
 resource, region, and requested change as facts; it does not create a renderer
 branch for its provider.
 
@@ -169,7 +169,7 @@ The projection is presentation evidence, never authority:
 - derive projection records purely from that value and hash their exact semantic
   bytes with the manifest;
 - render approval from the exact staged projection stored under that identity;
-- apply accepts only staged id plus hash, never replacement target, body, effect,
+- apply accepts only staged id plus hash, never replacement target, body, mutation,
   or projection inputs;
 - the receipt identifies the exact staged manifest and may add only outcome and
   evidence facts; it cannot rewrite approved records;
@@ -189,12 +189,14 @@ otherwise expose manifests, hashes, encoded payloads, or provider internals.
 
 ## CLI and stream contract
 
-`tool --help` is the tested human contract: effects, argv, streams, ordering,
+`tool --help` is the tested human contract: mutations, argv, streams, ordering,
 exits, environment/config precedence, credential timing, dependencies, pattern
 semantics, and one realistic pipeline. Explicit help succeeds on stdout; usage
 errors fail on stderr. Selector help gives value grammar, canonicalization, and a
 least-authority policy row, including AND within one row and alternatives across
-rows.
+approved global and ancestor-project rows. Project rows are not automatically
+trusted: Ink freezes the normalized effective policy and requires digest approval;
+child/session policy and the host floor may only narrow it.
 
 Keep argv unsurprising: options before operands, `--` ends options, `-` denotes a
 natural stream, secrets never enter argv, and unknown, incompatible, or trailing
@@ -250,7 +252,7 @@ interpreters, or generated-client machinery unless they are the named job.
 Use the smallest matrix that can falsify the actual claims:
 
 - help/contract agree with accepted argv and selectors;
-- main path and one forbidden near miss with zero unintended effect;
+- main path and one forbidden near miss with zero unintended mutation;
 - each reader selector has an adjacent no-match before access;
 - each mutator has admitted, approval-required, refused, drift, duplicate, and
   indeterminate/recovery outcomes as applicable;
@@ -278,7 +280,7 @@ Do not:
 - wrap or partially clone a utility whose whole admitted surface already fits;
 - combine read and mutation for code reuse;
 - expose a generic request/admin/registry platform;
-- invent invariant selectors, a universal effect ontology, or executable-name
+- invent invariant selectors, a universal mutation ontology, or executable-name
   branches in Ink's renderer;
 - let tools choose terminal styling or let presentation metadata grant authority;
 - treat argv prefixes, globs, or regexes as canonical path authority;
@@ -312,7 +314,7 @@ Report only:
 - **Presentation:** an HTTP mutator derives method, canonical target, and bounded
   body summary from one staged operation; Ink renders the exact stored projection
   without an `httpsend` branch and overlays receipt-bound status/final URL only.
-- **Presentation sprawl:** “support AWS changes” does not add an AWS effect enum or
+- **Presentation sprawl:** “support AWS changes” does not add an AWS mutation enum or
   renderer branch; the permission-sized infrastructure tool projects account,
   region, resource, requested change, outcome, and evidence through the elected
   generic vocabulary.

test/install-smoke.sh

@@ -3,7 +3,11 @@ set -eu
 
 repo=$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd -P)
 tmp=${TMPDIR:-/tmp}/ink-skills-smoke-$$
-trap 'rm -rf "$tmp"' EXIT HUP INT TERM
+cleanup() {
+    chmod -R u+w "$tmp" 2>/dev/null || :
+    rm -rf "$tmp"
+}
+trap cleanup EXIT HUP INT TERM
 mkdir -p "$tmp/home" "$tmp/project"
 
 list=$($repo/bin/ink-skills list)
@@ -11,28 +15,34 @@ printf '%s\n' "$list" | grep '^SKILL' >/dev/null
 printf '%s\n' "$list" | grep '^audit-ink-cli' >/dev/null
 printf '%s\n' "$list" | grep '^configure-ink-agent' >/dev/null
 
-HOME=$tmp/home $repo/bin/ink-skills install audit-ink-cli >"$tmp/install.tsv"
+HOME=$tmp/home $repo/bin/ink-skills link >"$tmp/link.tsv"
-grep "audit-ink-cli.*linked" "$tmp/install.tsv" >/dev/null
+grep "audit-ink-cli.*linked.*local" "$tmp/link.tsv" >/dev/null
 [ -L "$tmp/home/.ink/skills/audit-ink-cli" ]
 [ "$(readlink "$tmp/home/.ink/skills/audit-ink-cli")" = "$repo/skills/audit-ink-cli" ]
 
-HOME=$tmp/home $repo/bin/ink-skills install audit-ink-cli >"$tmp/reinstall.tsv"
+HOME=$tmp/home $repo/bin/ink-skills link "$repo/skills/audit-ink-cli" >"$tmp/relink.tsv"
-grep "audit-ink-cli.*unchanged" "$tmp/reinstall.tsv" >/dev/null
+grep "audit-ink-cli.*unchanged" "$tmp/relink.tsv" >/dev/null
 
-mkdir -p "$tmp/home/.ink/skills/configure-ink-agent"
+mkdir -p "$tmp/home/.ink/skills/collision"
-if HOME=$tmp/home $repo/bin/ink-skills install configure-ink-agent >/dev/null 2>"$tmp/collision.err"; then
+mkdir -p "$tmp/collision"
+cat >"$tmp/collision/SKILL.md" <<'EOF'
+---
+name: collision
+description: Fixture.
+---
+EOF
+if HOME=$tmp/home $repo/bin/ink-skills link "$tmp/collision" >/dev/null 2>"$tmp/collision.err"; then
     echo 'expected collision refusal' >&2
     exit 1
 fi
 grep 'refusing existing path' "$tmp/collision.err" >/dev/null
 
-HOME=$tmp/home $repo/bin/ink-skills install --project "$tmp/project" create-ink-tool >"$tmp/project.tsv"
+HOME=$tmp/home $repo/bin/ink-skills link --project "$tmp/project" "$repo/skills/create-ink-tool" >"$tmp/project.tsv"
 [ -L "$tmp/project/.ink/skills/create-ink-tool" ]
-grep "create-ink-tool.*linked" "$tmp/project.tsv" >/dev/null
+grep "create-ink-tool.*linked.*local" "$tmp/project.tsv" >/dev/null
 
-remote=$tmp/remote
+mkdir -p "$tmp/archive-tree/skills/remote-review"
-mkdir -p "$remote/skills/remote-review"
+cat >"$tmp/archive-tree/skills/remote-review/SKILL.md" <<'EOF'
-cat >"$remote/skills/remote-review/SKILL.md" <<'EOF'
 ---
 name: remote-review
 description: Review one remote fixture.
@@ -40,43 +50,53 @@ description: Review one remote fixture.
 
 # Remote review
 EOF
-git -C "$remote" init -q
+tar -cf "$tmp/skills.tar" -C "$tmp/archive-tree" skills
-git -C "$remote" config user.email ink-skills@example.invalid
+digest=$(sha256sum "$tmp/skills.tar" | awk '{print $1}')
-git -C "$remote" config user.name 'Ink Skills Test'
-git -C "$remote" add skills/remote-review/SKILL.md
-git -C "$remote" commit -qm fixture
-commit=$(git -C "$remote" rev-parse HEAD)
 
-mkdir -p "$tmp/remote-home"
+mkdir -p "$tmp/import-home"
-HOME=$tmp/remote-home INK_SKILLS_STORE=$tmp/store $repo/bin/ink-skills add --ref HEAD "$remote" skills/remote-review >"$tmp/add.tsv"
+HOME=$tmp/import-home INK_SKILLS_STORE=$tmp/store $repo/bin/ink-skills import "sha256:$digest" "$tmp/skills.tar" >"$tmp/import.tsv"
-remote_link=$tmp/remote-home/.ink/skills/remote-review
+remote_link=$tmp/import-home/.ink/skills/remote-review
 [ -L "$remote_link" ]
-case $(readlink "$remote_link") in
+[ "$(readlink "$remote_link")" = "$tmp/store/sha256/$digest/tree/skills/remote-review" ]
-    "$tmp/store/artifacts/"*"/$commit/skills/remote-review") ;;
+grep "remote-review.*linked.*artifact.*$digest" "$tmp/import.tsv" >/dev/null
-    *) echo 'remote link is not pinned to resolved commit' >&2; exit 1 ;;
+manifest=$tmp/import-home/.ink/skills/.ink-skills.tsv
-esac
-grep "remote-review.*linked.*$commit" "$tmp/add.tsv" >/dev/null
-manifest=$tmp/remote-home/.ink/skills/.ink-skills.tsv
 [ "$(wc -l <"$manifest")" -eq 2 ]
-awk -F '\t' -v commit="$commit" 'NR == 2 { exit !($1 == "remote-review" && $4 == commit && length($6) == 64) }' "$manifest"
+awk -F '\t' -v digest="$digest" 'NR == 2 { exit !($1 == "remote-review" && $2 == digest && $3 == "skills/remote-review") }' "$manifest"
 
-HOME=$tmp/remote-home INK_SKILLS_STORE=$tmp/store $repo/bin/ink-skills add --ref HEAD "$remote" skills/remote-review >"$tmp/readd.tsv"
+HOME=$tmp/import-home INK_SKILLS_STORE=$tmp/store $repo/bin/ink-skills import "sha256:$digest" "$tmp/skills.tar" skills/remote-review >"$tmp/reimport.tsv"
-grep 'remote-review.*unchanged' "$tmp/readd.tsv" >/dev/null
+grep 'remote-review.*unchanged' "$tmp/reimport.tsv" >/dev/null
 [ "$(wc -l <"$manifest")" -eq 2 ]
 
-printf '\nchanged\n' >>"$remote/skills/remote-review/SKILL.md"
+zero_digest=$(awk 'BEGIN { for (i = 0; i < 64; i++) printf "0" }')
-git -C "$remote" add skills/remote-review/SKILL.md
+if HOME=$tmp/import-home INK_SKILLS_STORE=$tmp/store $repo/bin/ink-skills import "sha256:$zero_digest" "$tmp/skills.tar" >/dev/null 2>"$tmp/digest.err"; then
-git -C "$remote" commit -qm changed
+    echo 'expected digest mismatch' >&2
-if HOME=$tmp/remote-home INK_SKILLS_STORE=$tmp/store $repo/bin/ink-skills add --ref HEAD "$remote" skills/remote-review >/dev/null 2>"$tmp/pin.err"; then
-    echo 'expected provenance collision after ref moves' >&2
     exit 1
 fi
-grep 'provenance collision' "$tmp/pin.err" >/dev/null
+grep 'SHA-256 mismatch' "$tmp/digest.err" >/dev/null
 
-if HOME=$tmp/remote-home INK_SKILLS_STORE=$tmp/store $repo/bin/ink-skills add 'https://user:secret@example.invalid/skills.git' >/dev/null 2>"$tmp/credential.err"; then
+printf '\nchanged\n' >>"$tmp/archive-tree/skills/remote-review/SKILL.md"
-    echo 'expected credentialed URL refusal' >&2
+tar -cf "$tmp/changed.tar" -C "$tmp/archive-tree" skills
+changed_digest=$(sha256sum "$tmp/changed.tar" | awk '{print $1}')
+if HOME=$tmp/import-home INK_SKILLS_STORE=$tmp/store $repo/bin/ink-skills import "sha256:$changed_digest" "$tmp/changed.tar" >/dev/null 2>"$tmp/provenance.err"; then
+    echo 'expected provenance collision after artifact changes' >&2
     exit 1
 fi
-grep 'credentialed HTTP URLs are refused' "$tmp/credential.err" >/dev/null
+grep 'provenance collision' "$tmp/provenance.err" >/dev/null
+
+mkdir -p "$tmp/unsafe/skills/unsafe"
+cat >"$tmp/unsafe/skills/unsafe/SKILL.md" <<'EOF'
+---
+name: unsafe
+description: Unsafe fixture.
+---
+EOF
+ln -s /etc/passwd "$tmp/unsafe/skills/unsafe/passwd"
+tar -cf "$tmp/unsafe.tar" -C "$tmp/unsafe" skills
+unsafe_digest=$(sha256sum "$tmp/unsafe.tar" | awk '{print $1}')
+if HOME=$tmp/import-home INK_SKILLS_STORE=$tmp/store $repo/bin/ink-skills import "sha256:$unsafe_digest" "$tmp/unsafe.tar" >/dev/null 2>"$tmp/unsafe.err"; then
+    echo 'expected symlink archive refusal' >&2
+    exit 1
+fi
+grep 'regular files and directories' "$tmp/unsafe.err" >/dev/null
 
 printf 'ok\n'

test/skills-smoke.sh

@@ -23,13 +23,20 @@ configure=$repo/skills/configure-ink-agent/SKILL.md
 grep 'access.*read.*write' "$configure" >/dev/null
 grep 'named agent policy is metadata-only' "$configure" >/dev/null
 grep 'no `INK_AGENT_HOME` contract' "$configure" >/dev/null
+grep 'applied as a restriction' "$configure" >/dev/null
 
 audit_cli=$repo/skills/audit-ink-cli/SKILL.md
 grep 'ink agent catalog' "$audit_cli" >/dev/null
 grep 'frozen `tool delegate` subject' "$audit_cli" >/dev/null
+grep 'additive alternatives' "$audit_cli" >/dev/null
+grep 'automatically trusted' "$audit_cli" >/dev/null
 
 create_tool=$repo/skills/create-ink-tool/SKILL.md
 grep 'stage/match/apply' "$create_tool" >/dev/null
 grep 'projection' "$create_tool" >/dev/null
+grep 'approved global and ancestor-project rows' "$create_tool" >/dev/null
+grep 'requires digest approval' "$create_tool" >/dev/null
+
+grep 'Empty project policy adds nothing' "$repo/README.md" >/dev/null
 
 printf 'ok\n'