feat(adapters): add Cline CLI adapter

.gitignore

@@ -29,6 +29,7 @@ env/
 adapters/codex/skills/adr-toolkit
 adapters/gemini-cli/skills/adr-toolkit
 adapters/antigravity/skills/adr-toolkit
+.cline/skills/adr-toolkit
 
 # Task-by-task implementation plans (superpowers subagent-driven-development
 # artifacts) — kept locally for reference, not part of the public tree.

README.md

@@ -39,6 +39,7 @@ of these adapters at it:
 | [Codex CLI](adapters/codex/) | Agent Plugins 1.0.0 manifest | [`adapters/codex/README.md`](adapters/codex/README.md) |
 | [Gemini CLI](adapters/gemini-cli/) | Extension manifest | [`adapters/gemini-cli/README.md`](adapters/gemini-cli/README.md) |
 | [Antigravity CLI](adapters/antigravity/) | Plugin manifest | [`adapters/antigravity/README.md`](adapters/antigravity/README.md) |
+| [Cline CLI](adapters/cline/) | Open Agent Skills (no manifest) | [`adapters/cline/README.md`](adapters/cline/README.md) |
 | Anything else | Generic fallback | [`adapters/generic/README.md`](adapters/generic/README.md) — needs only markdown-reading and shell |
 
 **No AI harness at all?** `create --interactive` runs the same interview

adapters/cline/README.md

@@ -0,0 +1,116 @@
+# Cline CLI adapter
+
+Cline CLI installs skills through the **open Agent Skills** standard — the same
+`SKILL.md` + `skills/` convention this toolkit already ships — rather than a
+harness-specific manifest file like the Codex, Gemini, and Antigravity adapters
+use. There is no `plugin.json`/`gemini-extension.json` equivalent for Cline
+skills, so this adapter is **README-only** (like `adapters/generic/`): it
+documents how to point Cline at the existing `skills/adr-toolkit/` package.
+**Manually verified against Cline CLI 3.0.61** (`cline --version`): discovery,
+install, and the installed script layer all work — see "Verification status"
+below.
+
+Cline CLI exposes a `skill` subcommand that forwards to the open skills CLI
+(`npx skills`), and it discovers skills from the standard agent locations
+(`~/.agents/skills/` globally, `.cline/skills/` per project). Because
+`skills/adr-toolkit/SKILL.md` already carries the two fields Cline requires —
+`name` matching its directory and `description` (under 1024 characters) — the
+package installs as-is with no wrapper.
+
+## Install
+
+### From the published repository (recommended)
+
+The repository is public, so Cline installs the skill straight from GitHub:
+
+```bash
+cline skill add SHcommit/ADR-toolkit --global
+```
+
+Add `-y`/`--yes` to skip the confirmation prompt. Drop `--global` to install
+project-level (into the current project's `.cline/skills/`) instead of globally.
+
+### From a local clone
+
+A local checkout works the same way:
+
+```bash
+cline skill add "$(pwd)/skills/adr-toolkit" --global
+```
+
+or symlink the package into Cline's skill directory yourself:
+
+```bash
+# project-level
+mkdir -p .cline/skills
+ln -s "$(pwd)/skills/adr-toolkit" .cline/skills/adr-toolkit
+
+# global
+mkdir -p ~/.agents/skills
+ln -s "$(pwd)/skills/adr-toolkit" ~/.agents/skills/adr-toolkit
+```
+
+The symlink is created at install time, not committed to any repo — committing a
+real symlink breaks on Windows checkouts that don't have `core.symlinks` enabled,
+which this project's CI can't assume.
+
+### Confirm
+
+```bash
+cline skill list
+```
+
+should list `adr-toolkit`.
+
+### Script-layer fallback
+
+Either way, run
+`python skills/adr-toolkit/scripts/adr.py preflight --json` from your target
+repository to confirm the script layer works standalone — this is the verified
+working path regardless of skill-discovery status.
+
+## Why there's no manifest here
+
+Cline's "plugin" mechanism (`cline plugin install`, driven by a `package.json`
+`cline` field) is for **TypeScript `AgentPlugin` modules** that register tools
+and lifecycle hooks — a different extension point from a skill. ADR Toolkit is a
+Python skill, so a TS plugin wrapper would be a rewrite with no benefit. The
+always-on-hook use case (auto-running `check` on session start) is deliberately
+out of scope — see `project-roadmap.md`'s "Harness parity" note.
+
+## Verification status
+
+Manually verified against Cline CLI 3.0.61 (`cline --version`) in an isolated
+`HOME=$(mktemp -d)` so no state was written to the real `~/.cline`/`~/.agents`.
+
+```
+$ cline skill add SHcommit/ADR-toolkit --list
+...
+◇  Found 1 skill
+│    adr-toolkit
+│      Initialize, record, and check Architecture Decision Records by inspecting the repository and existing decisions before asking questions.
+
+$ cline skill add SHcommit/ADR-toolkit --yes --global
+...
+◇  Installed 1 skill
+│  ✓ adr-toolkit (copied)
+│    → ~/.agents/skills/adr-toolkit
+```
+
+The installed snapshot lands under `~/.agents/skills/adr-toolkit/` and carries
+the whole `skills/adr-toolkit/` package. The script layer was run directly out of
+it against a scratch git repository, producing correct `"ok": true` output for
+`preflight`, `init --dir docs/decisions`, and `validate --dir docs/decisions` —
+matching the Codex, Gemini CLI, and Antigravity adapters' verified depth.
+
+Two details worth knowing:
+
+- **The install location is `~/.agents/skills/`, not `~/.cline/...`.** The
+  skills CLI reports `~/.agents/skills/adr-toolkit` as the install path (the open
+  Agent Skills global directory Cline reads), even though Cline's CLI reference
+  mentions a `~/.cline/data/settings/skills/` global directory. Trust
+  `cline skill list` for where a given Cline version actually looks.
+- **A project's own `skills/` directory is auto-detected.** Running
+  `cline skill list` inside this repository reports `adr-toolkit` from
+  `./skills/adr-toolkit` as a project skill, so a checkout of this repo is already
+  a working Cline project skill with no install step.

changelog.md

@@ -4,6 +4,11 @@ Lightweight human-readable summary of meaningful repository changes.
 
 ## Unreleased
 
+- Added a Cline CLI adapter (`adapters/cline/`) so Cline CLI and ClinePass users
+  can install the `skills/adr-toolkit` package. Cline installs skills through the
+  open Agent Skills standard (SKILL.md), so the adapter is README-only — no
+  manifest — documenting `cline skill add SHcommit/ADR-toolkit` plus a manual
+  symlink fallback. Manually verified against Cline CLI 3.0.61.
 - Expanded `improvements.md` backlog with High and Medium priority items: ReDoS cross-platform safety, 2-phase atomic transaction rollback for `supersede`, ADR overlap/similarity Eval framework, weekly automated maintenance workflows, PR significance bot, `adr lint --fix` auto-repair, interactive HTML graph viewer, and code drift detection.
 
 ## v0.3.2 (2026-09-02)

handoff.md

@@ -2,7 +2,12 @@
 
 ## Current task
 
-Expanded `improvements.md` with High and Medium backlog items covering ReDoS cross-platform safety, 2-phase atomic transaction rollback, ADR overlap/similarity Eval infrastructure, weekly maintenance automation, PR significance bot, frontmatter auto-linter, interactive graph visualization, and code drift detection.
+Added a Cline CLI adapter (`adapters/cline/`) so Cline CLI and ClinePass users
+can install the `skills/adr-toolkit` package. Cline installs skills through the
+open Agent Skills standard (SKILL.md), so the adapter is README-only — no
+manifest. Discovery, install, and the installed script layer were manually
+verified against Cline CLI 3.0.61. Tracked in GitHub issue #19; work is on the
+`feature/cline-cli-adapter` branch.
 
 ## Scope
 
@@ -17,7 +22,13 @@ Expanded `improvements.md` with High and Medium backlog items covering ReDoS cro
 
 ## Next step (for a new session picking this up cold)
 
-Review the newly expanded `improvements.md` High/Medium items and pick an implementation candidate (e.g. `adr lint --fix` or ReDoS cross-platform guard).
+The Cline adapter work is implemented but not yet committed. Run
+`python3 -m pytest tests/unit tests/integration -q` and
+`python3 scripts/sync_version.py --check`, then commit on
+`feature/cline-cli-adapter`, push, open a PR into `develop`, and merge via the
+Git Flow process (then delete the short-lived branch). CI's `harness-parity` job
+still covers only Codex/Gemini; extending it to Cline CLI is a deferred
+follow-up (non-interactive `npx skills` verification needs design).
 
 
 1. `improvements.md`'s `### Low` → audit-report sub-group has exactly 1

tests/unit/test_cline_adapter.py

@@ -0,0 +1,37 @@
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parent.parent.parent
+CLINE_README = REPO_ROOT / "adapters" / "cline" / "README.md"
+SKILL_MD = REPO_ROOT / "skills" / "adr-toolkit" / "SKILL.md"
+
+
+def test_cline_adapter_readme_exists_and_documents_install():
+    text = CLINE_README.read_text(encoding="utf-8")
+    assert "cline skill add" in text
+    assert "skills/adr-toolkit" in text
+    assert "SKILL.md" in text
+
+
+def test_cline_adapter_documents_skill_discovery_locations():
+    text = CLINE_README.read_text(encoding="utf-8")
+    assert ".cline/skills" in text
+    assert "~/.agents/skills" in text
+
+
+def test_skill_frontmatter_satisfies_cline_requirements():
+    # Cline requires `name` to match its directory and `description` (< 1024
+    # chars). The canonical package already carries both, so no adapter-local
+    # manifest is needed for the Cline adapter.
+    text = SKILL_MD.read_text(encoding="utf-8")
+    assert "name: adr-toolkit" in text
+    assert SKILL_MD.parent.name == "adr-toolkit"
+    # Extract the description line from the YAML frontmatter and confirm it is
+    # present and under Cline's documented 1024-character limit.
+    lines = text.splitlines()
+    desc_lines = [
+        line[len("description:"):].strip()
+        for line in lines
+        if line.startswith("description:")
+    ]
+    assert len(desc_lines) == 1
+    assert 0 < len(desc_lines[0]) < 1024

tests/unit/test_readme.py

@@ -33,3 +33,9 @@ def test_readme_documents_harness_adapters_including_antigravity():
     assert "[Antigravity CLI](adapters/antigravity/)" in text
     assert "adapters/antigravity/README.md" in text
 
+
+def test_readme_documents_cline_cli_adapter():
+    text = README.read_text(encoding="utf-8")
+    assert "[Cline CLI](adapters/cline/)" in text
+    assert "adapters/cline/README.md" in text
+