Adds an opt-in compression interceptor that buffers Anthropic
/v1/messages requests, runs IntelligentContextManager over the
messages array, and forwards the (possibly trimmed) body upstream.
All other paths, methods, and content-types stay on the original
streaming passthrough — so existing operators see zero change.
Behaviour gates ALL must be true to buffer + compress:
- --compression flag (or HEADROOM_PROXY_COMPRESSION=1)
- method == POST
- path == /v1/messages
- Content-Type: application/json
- ICM constructed successfully at startup
Falls through to streaming on any failure: parse, missing fields,
unknown model, body-too-large. Compression must never break a
request — that's the safety contract.
Model context windows come from a vendored LiteLLM snapshot at
crates/headroom-proxy/data/model_prices_and_context_window.json
parsed once into an OnceLock<HashMap>. Refresh via
scripts/refresh_model_limits.sh. Rationale documented inline:
hardcoded tables silently rot; LiteLLM is the canonical source
the entire LLM-tooling ecosystem relies on.
New tests:
- 16 unit tests across compression::{anthropic, icm, model_limits}
- 5 integration tests: off-passthrough, on-short-passthrough,
on-oversized-trim, on-non-json-skip, on-non-llm-path-skip
Verification:
- cargo test --workspace -> 884 passed, 0 failed
- cargo clippy --workspace -- -D warnings -> clean
- cargo fmt --check -> clean
The Anthropic token-mode handler walked past prefix_tracker.frozen_message_count
whenever an upcoming tool_result's content-hash matched comp_cache._stable_hashes
or should_defer_compression returned True. That conflated content equality with
positional cache membership.
Anthropic's prefix cache is POSITIONAL: bytes 0..K cached, anything past K is
fresh. _stable_hashes is content-keyed and grows unbounded. In long Claude Code
sessions where tool_result content rhymes across turns (repeated system prompts,
repeated file reads, repeated tool descriptions), the walker advanced
frozen_message_count to len(messages) on every turn and the pipeline produced
transforms_applied=[] on 73% of requests in user SvenMeyer's reported session
(headroom-stats-2026-05-01.json: 74 of 101 eligible requests "prefix_frozen") —
even after the prior fix in 44944fb. The 15 requests that did compress averaged
21%, proving compression itself works when reached.
Fix: delete the walker. The freeze boundary is now
frozen_message_count = min(
prefix_tracker.frozen_message_count, # positional ground truth
comp_cache.compute_frozen_count(messages), # local cache lower bound
)
compute_frozen_count's use of _stable_hashes can only LOWER the freeze via the
min clamp, never raise it past prefix_tracker's value. For any position in the
gap [compute_frozen_count, prefix_tracker.frozen_count], recompressing produces
byte-stable output (compression is deterministic on input content), so
Anthropic's prefix cache stays valid.
Cross-handler verification:
* OpenAI handler (proxy/handlers/openai.py:358-382) does not have this walker
— uses only compute_frozen_count. Codex routes through OpenAI handler. Both
unaffected.
* Streaming and non-streaming both invoke anthropic_pipeline.apply() before the
upstream call. One fix covers both paths.
* Cache mode (is_cache_mode) takes the _extract_cache_stable_delta path and is
independent of the walker. Unaffected.
Tests: six new regression tests lock down the post-fix invariants — clamp to
min(prefix_tracker, compute_frozen_count); fresh tool_result whose hash matches
old _stable_hashes entry is not frozen; frozen prefix byte-stable across the
pipeline; 10-turn session produces non-empty compression suffix every turn;
streaming and non-streaming compute identical frozen_message_count; OpenAI
handler never calls the walker functions. Plus scripts/smoke_issue_327.py
(gated by RUN_LIVE_API=1) drives a 10-turn conversation against
api.anthropic.com in both shapes (string + list-of-blocks) and both modes
(streaming + non-streaming).
ci-precheck clean. 191 tests pass.
Follow-ups (separate PRs):
* Fix _cache perpetually empty (anthropic.py result.messages != working_messages
comparison rarely fires in token mode).
* Cap _stable_hashes with bounded LRU + 1h TTL — hygiene only after the freeze
gate is removed.
* List-shape tool_result content gates at content_router.py:1975 and
intelligent_context.py:657 (cluster A from the audit).
Five gates broke on the 2026-04-27 push of the smart_crusher branch.
Each is fixed below; the second half adds a `make ci-precheck` target
(plus an installable git pre-push hook) so the same dance never happens
again.
Failures fixed:
1. cargo fmt — 22 files had formatting drift introduced over the
stage 3c.1 work. `cargo fmt --all` reformatted them; no semantic
changes. `cargo test --workspace` still green (388 + supporting).
2. wheels job (macOS x86_64) — `fastembed -> ort -> ort-sys` does not
publish prebuilt ONNX Runtime binaries for `x86_64-apple-darwin`.
Removed that target from `.github/workflows/rust.yml`'s wheels
matrix. Apple Silicon (`aarch64-apple-darwin`) covers macOS
distribution; Intel macOS users can build from source. The matrix
now has 2 targets: linux x86_64 + macOS aarch64.
3. test-extras (relevance.py) — `tests/test_relevance.py::TestSmartCrusherIntegration`
constructs a `SmartCrusher`, which hard-imports `headroom._core`
since the python implementation was retired in stage 3c.1b. The
test-extras job didn't build the rust extension. Added the same
`maturin build + symlink` block the main `test` job uses.
4. smoke-test (eval.yml) — same root cause:
`compression_only.evaluate_ccr_lossless` instantiates a SmartCrusher.
Same fix: build the rust extension before the smoke test runs.
5. commitlint — three rules tripped:
- `subject-case` rejects PascalCase identifiers in subjects, but
the project deliberately names classes (SmartCrusher, HfTokenizer,
ContentRouter, DiffCompressor) in commit subjects. Disabled.
- `footer-leading-blank` is a warning that the wagoid action turns
into a CI failure; lines like `Module: foo.rs` in our bodies
match the conventional footer pattern and trip it. Disabled.
- `type-enum` doesn't include `parity`, but the project ships
parity-test infrastructure as its own concern (separate from
`test:`); added `parity` to the allowed types.
Pre-push verification — the prevention half:
`make ci-precheck` runs all of the above CI gates locally:
- `ci-precheck-rust`: cargo fmt --check + clippy + test --workspace.
- `ci-precheck-python`: builds the rust extension via maturin, then
runs the smart_crusher-affected python test files (185 tests across
test_transforms/, test_relevance*, test_ccr, test_acceptance,
test_critical_fixes, test_quality_retention).
- `ci-precheck-commitlint`: `npx commitlint --from origin/main --to
HEAD` against the same config CI uses. Skipped silently if npx is
not on PATH (install Node 18+ to enable).
`make install-git-hooks` (or `scripts/install-git-hooks.sh`) installs
a git pre-push hook that runs `make ci-precheck` automatically.
Bypass with `--no-verify` only when truly needed.
When new CI gates land in `.github/workflows/`, mirror them into a
`make ci-precheck-*` target. The Makefile is the local mirror of the
CI configuration; keeping them in sync is a load-bearing invariant.
Verification: `make ci-precheck` runs green on this commit.
The python `DiffCompressor` is replaced by a thin pyo3-backed shim that
delegates to `headroom._core.DiffCompressor`. There is no python
implementation and no env-var fallback — the wheel is a hard import.
Why now: opt-in defaults don't drive python retirement. Byte-equal
parity was already proven across 27 fixtures (stage 3a); keeping a
shadow python impl behind a flag is a permanent maintenance cost with
no operational benefit. Stage 3b deletes ~700 lines of python parser /
scorer / formatter code; the rust crate has its own coverage.
Surface preserved:
- `headroom.transforms.diff_compressor.DiffCompressor` — same class
name, same `__init__`, same `compress(content, context)` shape.
Returns python `DiffCompressionResult` dataclasses so call sites that
destructure with `asdict()` work unchanged.
- `DiffCompressorConfig` and `DiffCompressionResult` dataclasses kept.
- Sidecar `compress_with_stats(...)` exposes the rust-only
`DiffCompressorStats` (per-file hunk drops, context lines trimmed,
file_mode normalizations) for observability.
Removed:
- Python parser / scorer / formatter (~700 lines).
- Internal `DiffHunk` / `DiffFile` parser dataclasses (rust crate has
parallel coverage).
- 12 tests that probed `_parse_diff` / `_score_hunks` or the deleted
parser dataclasses. The 29 public-API tests in `test_diff_compressor.py`
remain and now exercise the rust backend through the same import path.
- `HEADROOM_DIFF_COMPRESSOR_BACKEND` env var — no longer meaningful.
Build:
- `scripts/build_rust_extension.sh` runs `maturin develop` and symlinks
the built `.so` into `headroom/` so `import headroom._core` resolves
past the in-tree package shadowing the maturin overlay.
- `.gitignore` excludes the symlinks and allowlists the build script.
Tests:
- 544 transforms pass; 33 rust-vs-fixture parity tests guard the pyo3
bridge against regressions (`tests/test_transforms/test_diff_compressor_rust_parity.py`).
- Mypy clean.
`.gitattributes` declares `*.py text eol=lf` and `*.sh text eol=lf`, but
74 files (73 .py, 1 .sh) are stored in the index with CRLF line endings,
violating that contract. Every macOS/Linux clone reports these files as
"modified" on fresh checkout because git's diff engine sees the stored
bytes don't match the attribute contract, even though the working tree
and index match byte-for-byte.
Running `git add --renormalize .` rewrites each affected blob so the
stored form matches the attribute declaration. No semantic changes —
every affected file's diff is "N insertions, N deletions" with inserts
and deletes being the same lines modulo line endings.
Follow-up commit adds `.git-blame-ignore-revs` so `git blame` / GitHub
blame skip this mechanical commit.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
asyncio.timeout was added in Python 3.11, but the project supports >=3.10.
The test_repro_codex_replay_smoke test was crashing on Python 3.10 CI with
"AttributeError: module 'asyncio' has no attribute 'timeout'".
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Add websockets to the dev extra so the repro harness smoke test can import
its websocket client dependency in the CI test matrix. Also apply ruff
formatting to the files the formatter check was rejecting so the 3.12 lint
job passes.
- Route --json output cleanly: JSON goes to stdout (machine-readable),
human-readable summary goes to stderr. Without --json, the human
summary stays on stdout as before. Makes piping the harness into
jq / other tools trivial without losing operator visibility.
- Add distinct exit codes so CI and shell wrappers can branch on the
failure class: 0 success, 1 crash, 2 proxy_unreachable, 3 livez
threshold exceeded, 4 warmup failed, 130 SIGINT (already correct).
Smoke test updated to assert EXIT_PROXY_UNREACHABLE instead of 1.
- Replace flat 50-250ms jitter in the Anthropic-client retry loop with
exponential backoff + 50-150% jitter
(base=250ms, max=5000ms, attempt counter). Matches the proxy's own
jitter_delay_ms helper; inlined to keep the script free of proxy
package imports.
Add a workflow-validation CI job that installs actionlint and act,
checks the release and Docker workflows against checked-in event
fixtures, and shares the same validation script developers can run
locally.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
- publish-pypi: add permissions: id-token: write for OIDC trusted publishing
- publish-npm: add npm run build before npm publish for both packages
- publish-github-packages: add npm run build, use --registry for GPR
- version-sync: add update_openclaw_package_json to sync headroom-ai dep range
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Align Docker-native wrapper help and runtime behavior with the Python install contract, including persistent deployment metadata, baked install-image defaults, and explicit unsupported wrap targets.
Harden the Python persistent-install path with profile validation, safer provider-scope handling, Windows environment restoration, runtime parity improvements, and rollback-safe apply/update behavior.
Update README, Docker install docs, CI, and focused regressions to cover the Windows BOM failure, wrapper parity, compose coverage, and Docker-native wrap behavior.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Tighten Docker-native bash and PowerShell wrapper validation for wrap and proxy flows, pin the bash wrapper to the install-time interpreter, clean up failed persistent container starts, and extend docs, CI, e2e, and native installer coverage for persistent Docker installs.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Add host-managed OpenClaw wrap and unwrap flows to the Docker-native wrappers so the installed headroom script can configure the OpenClaw plugin on the host while keeping Headroom itself in Docker. Reuse hidden prepare-only hooks for OpenClaw config payloads, preserve existing plugin metadata on unwrap, and update the Docker-native and integration docs to reflect the supported flow.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Add system-native install scripts and host wrappers for running Headroom from Docker while keeping wrapped tools on the host. Document the Docker-native path, add a complete CLI reference with help output and parity details, and add support for root help/version aliases and proxy env-based binding behavior.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>