## Description
Removes both third-party CLI context tools — **rtk** and **lean-ctx** —
and with them the context-tool selector itself. Headroom no longer
downloads, installs or configures either one, and there is no
replacement.
The previous pass (#2344) gated only three entry points inside
`headroom/cli/wrap.py`. That left the feature reachable in practice:
| Gap | Effect |
|---|---|
| `scripts/install.sh:1544`, `install.ps1:1681` | Ran `rtk init --global
--auto-patch` from bash/PowerShell, **bypassing the Python gate
entirely** — `curl \| sh` still wrote a Claude Code `PreToolUse` hook
regardless of `HEADROOM_RTK` |
| `wrap.py` `_setup_context_tool_for_agent` | **`wrap openhands` was
broken by default**: `rtk_required=True` met a gate returning `None` →
`SystemExit(1)`. Invisible because all 8 openhands tests patched
`_ensure_rtk_binary` to a fake path |
| `proxy/helpers.py`, `subscription/tracker.py` | Proxy shelled out to
`rtk gain` from `/stats`, the dashboard and `headroom perf`; the tracker
polled it per contribution (`_RTK_WIRING_DEFAULT = "enabled"`) |
| No cleanup path | Nothing removed artifacts an earlier default had
installed, so a machine that once ran the old default kept rtk in the
loop forever (#1669, #1955) |
Also worth noting: the rtk binary download had **no SHA or signature
verification** — only `rtk --version` as a smoke test.
## Type of Change
- [x] Bug fix (non-breaking change that fixes an issue)
- [ ] New feature (non-breaking change that adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
- [ ] Performance improvement
- [x] Code refactoring (no functional changes)
## Changes Made
**Removed** — `headroom/rtk/` and `headroom/lean_ctx/` packages,
`headroom/cli/wrap_rtk_metrics.py`, `_selected_context_tool` /
`_setup_context_tool_for_agent` / `_VALID_CONTEXT_TOOLS`, the `--rtk` /
`--no-rtk` / `--no-project-rtk` / `--keep-rtk` flags across all 18 wrap
subcommands, `HEADROOM_RTK*`, the proxy-side `rtk gain` polling, the
dashboard CLI-filtering panel (rows + all 8 `cliFiltering*` Alpine
getters), `paths.rtk_path()` / `lean_ctx_path()`, the SDK path helpers,
`benchmarks/rtk_loop_learn_eval.py`, and the `headroom/rtk/**` CI path
filters.
**Fails loudly, not silently** — `--context-tool` / `--no-context-tool`
/ `HEADROOM_CONTEXT_TOOL` are kept solely to error out. They live in
shell profiles, aliases and CI jobs, and accepting them as a no-op would
read as Headroom having quietly stopped working. The installers reject
them too, which matters more than it looks: their arg parsers forward
the first unknown flag **and everything after it** to the wrapped tool,
so a leftover `--no-rtk` would have silently swallowed a following
`--port` and then been ignored downstream.
**New `headroom/context_tool_cleanup.py`** — deleting the code cannot
help a machine that already ran the old default, since the hooks,
binaries and injected guidance are durable on disk.
`purge_context_tool_artifacts()` runs once per `wrap`/`unwrap` and
removes the registered hook entries, the generated hook scripts, the
Headroom-managed `~/.local/bin` symlinks, the vendored
`~/.headroom/bin/{rtk,lean-ctx}` binaries, the `lean-ctx` MCP server
entry and the marker-fenced instruction blocks. Deliberately
conservative: idempotent, **skips** a malformed config rather than
overwriting it, and only unlinks a symlink resolving inside Headroom's
own bin dir so a user's own build is untouched. It reports on
**stderr**, because `wrap/unwrap openclaw --prepare-only` emit
machine-readable JSON on stdout as their entire contract. Skipped for
`wrap selfheal` (runs from a SessionStart hook; must not race Claude
Code's writer for `~/.claude.json`) and for `--help`, which must stay
read-only.
**Client-config hardening** (discovered while investigating a "corrupted
Serena settings file" report) — `wrap.py` reset a settings file to `{}`
when an existing file would not parse, then wrote that back. One
hand-edited typo or a transient `EACCES`/`EINTR` on a valid file
destroyed the user's `permissions`, `env` and `hooks`, on **every
`headroom wrap claude`**. It now refuses to write. Separately,
`fsutil.write_text` is now atomic (temp file + `fsync` + `os.replace`),
fixing all 14 non-atomic client-config writes at once; it follows
symlinks rather than replacing them (dotfile managers) and preserves an
existing file's mode.
**Deliberately kept** — `rtk` stays in the wrapper-peel list in
`transforms/content_router.py`. It sits beside `sudo`/`env`/`timeout` as
shell-command grammar, so `rtk cat f` is still classified as a file read
for anyone running their own rtk install, which the purge intentionally
leaves alone.
## Testing
- [x] Unit tests pass (`pytest`)
- [x] Linting passes (`ruff check .`)
- [x] Type checking passes (`mypy headroom`)
- [x] New tests added for new functionality
- [x] Manual testing performed
### Test Output
```text
$ ruff check headroom/ tests/ e2e/ --exclude headroom/dashboard/templates
All checks passed!
$ ruff format --check headroom/ tests/ e2e/ --exclude headroom/dashboard/templates
1255 files already formatted
$ mypy headroom/
Success: no issues found in 508 source files
$ pytest tests/test_context_tool_cleanup.py -q
11 passed
$ pytest tests/test_fsutil.py -q
12 passed
$ pytest tests/test_cli/test_wrap_codex.py -q # 89 tests
89 passed in 431.68s
$ pytest tests/test_cli/test_wrap_opencode.py -q
39 passed in 257.46s
$ pytest tests/test_cli/test_wrap_helpers.py -q
45 passed
$ pytest tests/test_paths.py -q
75 passed
$ pytest tests/test_cli/test_unwrap_claude.py -q
14 passed
$ pytest tests/test_proxy_savings_history.py -q
39 passed
$ pytest tests/test_cli/test_wrap_copilot.py -q
27 passed
$ pytest tests/test_cli/test_wrap_zcode.py -q
20 passed
$ pytest tests/test_subscription_tracker.py -q
9 passed
$ pytest tests/test_proxy_dashboard_stats_cache.py -q
5 passed, 1 skipped
```
Repo-wide grep for 14 removed symbols (`headroom.rtk`,
`headroom.lean_ctx`, `_ensure_rtk_binary`, `_selected_context_tool`,
`_get_context_tool_stats`, `rtk_path`, `lean_ctx_path`,
`wrap_rtk_metrics`, `HEADROOM_RTK`, `cli_tokens_avoided`,
`tokens_saved_rtk`, …) across `*.py`, `*.ts`, `*.sh`, `*.ps1`, `*.yml`,
`*.html`: **zero hits**.
Notable test changes: `test_wrap_openhands.py` no longer patches
`_ensure_rtk_binary` and asserts `wrap openhands --prepare-only` exits 0
unpatched — the regression that was previously masked.
`test_wrap_continue.py` and `test_wrap_hintfile_agents.py` were removed
(every test drove RTK instruction injection). A new
`test_subscription_tracker.py::test_load_state_written_before_cli_context_tools_were_removed`
proves a pre-removal `subscription_state.json` still loads.
## Real Behavior Proof
- **Environment:** macOS 15.4 (darwin 25.4.0), Python 3.12.6, Headroom @
this branch, real `~/.headroom` and `~/.claude` on the dev machine.
- **Exact command / steps and observed result:**
```text
# 1. Retired flag fails loudly instead of silently no-op'ing
$ headroom wrap codex --prepare-only --context-tool rtk
Error: CLI context tools (rtk, lean-ctx) have been removed from Headroom: they
rewrote shell commands through a third-party binary Headroom no longer manages.
Drop --context-tool / --no-context-tool and unset HEADROOM_CONTEXT_TOOL;
`headroom wrap` uninstalls what they left behind on first run.
$ HEADROOM_CONTEXT_TOOL=lean-ctx headroom wrap codex --prepare-only
Error: CLI context tools (rtk, lean-ctx) have been removed from Headroom: ...
# 2. install.sh rejects the retired flags (extracted parse_wrap_args harness)
['--no-rtk', '--port', '9999'] rc=1 ERROR: CLI context tools ... Drop --no-rtk
['--context-tool=rtk'] rc=1 ERROR: CLI context tools ... Drop --context-tool
$ bash -n scripts/install.sh # syntax OK
# 3. Purge ran against the real machine, which had all the orphaned artifacts
$ python -c "from headroom.context_tool_cleanup import purge_context_tool_artifacts; ..."
removed ~/.headroom/bin/lean-ctx (51 MB)
removed ~/.headroom/bin/rtk (7.7 MB)
removed ~/.local/bin/rtk (symlink into ~/.headroom/bin)
removed ~/.claude/hooks/rtk-rewrite.sh
removed 8 lean-ctx-* hook scripts
# ~/.claude.json afterwards: 90 top-level keys, 19 projects, mcpServers unchanged
# → ~59 MB reclaimed, no unrelated key touched
# 4. stdout stays machine-readable while the purge reports (planted a fake artifact)
$ headroom wrap openclaw --prepare-only --gateway-provider-id codex >out 2>err
$ cat out
{"enabled":true,"config":{"proxyPort":8787,...}} # parses as JSON
$ cat err
Retired CLI context tool cleanup: removed /Users/tcms/.headroom/bin/rtk
# 5. --help is inert (planted artifact survives), a real run purges
$ headroom wrap codex --help → artifact survived: CORRECT
$ headroom wrap openclaw --prepare-only → purged: CORRECT
# 6. MCP purge dry-run against a copy of the real 82 KB ~/.claude.json
top-level keys 90 -> 90; projects 19 -> 19; LOST keys: none
all content outside mcpServers byte-identical: True
```
Dashboard rendered via the Playwright test after the panel removal:
"Token Savings" shows only `Proxy 0 (0.0%)` / `Of total wire: 36.86%`,
and "Token Usage" reads Before Compression → Proxy Removed → After
Compression with no "Filtered (this session)" row. Nothing below the
removed panel broke.
- **Not tested:** Windows and Linux (macOS only) — `install.ps1` is
verified by brace-balance and inspection, not executed, since no `pwsh`
is available locally. The wrap e2e suite (`e2e/wrap/run.py`) was updated
but not run; it needs the Docker e2e image. `serena project index`
interaction is exercised in the stacked base PR.
## Review Readiness
- [x] I have performed a self-review
- [x] This PR is ready for human review
## Checklist
- [x] My code follows the project's style guidelines
- [x] I have performed a self-review of my code
- [x] I have commented my code, particularly in hard-to-understand areas
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [x] I did **not** edit `CHANGELOG.md` — it is generated by
release-please from my Conventional Commit PR title (a CI guard enforces
this)
## Additional Notes
**Stacked on #2676** (`tejas/serena-config-bootstrap`) — please merge
that first; this PR's base should then be retargeted to `main`, or it
will read as containing that fix too.
**Breaking-change migration for users:**
- Drop `--rtk`, `--no-rtk`, `--no-project-rtk`, `--keep-rtk`,
`--context-tool`, `--no-context-tool` from any alias, script or CI job,
and unset `HEADROOM_RTK*` / `HEADROOM_CONTEXT_TOOL`. They now error
rather than being ignored, so the failure is immediate and
self-explaining.
- Previously-installed artifacts are purged automatically on the next
`wrap`/`unwrap`; no manual cleanup needed.
- `headroom perf --json` no longer carries a `cli_filtering` key, and
`/stats` no longer returns a `context_tool` section.
**Docs:** `docs/rtk-architecture.md` deleted; RTK/lean-ctx removed from
`README.md`,
`docs/content/docs/{configuration,opencode,grok-build,docker-install,filesystem-contract}.mdx`,
`docs/observability.md` and the matching `wiki/` pages.
`REALIGNMENT/09-phase-G-rtk-observability.md` is marked SUPERSEDED
rather than deleted, to keep the planning record.
**Follow-ups not in scope:** `_emit_wrap_interrupted` was deleted as
dead code — its only caller was the `except KeyboardInterrupt` guarding
the binary download, so with no download there is nothing slow left to
interrupt.
Tejas Chopra
e0ce4b1d48