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JD Davis 1d2b76e72e
fix: harden persistent install startup (#1851)
## Description

Hardens persistent install startup and proxy compression behavior for
issue #1843. Repeated `headroom install start` / scheduled ensure calls
no longer spawn duplicate runtimes by default, and `/v1/compress` now
fails open on compression timeout instead of returning a 503. The PR
also adds a machine-readable platform feature matrix and app-level
stabilization tests for health, compression functionality, timeout
behavior, and matrix evidence.

Refs #1843

## Type of Change

- [x] Bug fix (non-breaking change that fixes an issue)
- [ ] New feature (non-breaking change that adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [x] Documentation update
- [x] Performance improvement
- [ ] Code refactoring (no functional changes)

## Changes Made

- Wrapped direct persistent deployment starts with the existing
profile-local runtime start lock.
- Made `headroom install start` idempotent when the deployment is
already healthy.
- Added wedged-runtime handling: if a PID is running but `/readyz` does
not recover inside the grace window, stop it before starting again.
- Kept `install agent ensure` inside the already-held lock while
delegating to the shared start helper.
- Changed `/v1/compress` timeout behavior from `503 compression_timeout`
to fail-open `200` with original messages, `compression_skipped: true`,
and `skip_reason: compression_timeout`.
- Added `tests/test_platform_stabilization_functional.py` covering real
FastAPI health/compression routes, successful compression metrics,
timeout fail-open speed, and a real JSON tool payload that reduces
tokens.
- Added `docs/platform-feature-matrix.json` and
`docs/platform-stabilization.md` for Linux/macOS/Windows hardening
coverage and known gaps.
- Strengthened matrix tests so cited local test/workflow paths must
exist.

## 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
# Clean source tree without copied Rust extension: functional module is skipped locally, as CI copies _core from the built wheel.
> python -m pytest tests/test_install tests/test_cli/test_install_cli.py tests/test_platform_feature_matrix.py tests/test_platform_stabilization_functional.py -q
collected 120 items / 1 skipped
119 passed, 2 skipped in 17.08s

> python -m ruff check headroom/proxy/handlers/openai.py tests/test_platform_stabilization_functional.py tests/test_platform_feature_matrix.py
All checks passed!

# Local Windows compiled-core proof:
> python -m maturin build --profile ci --out dist-local
Built wheel for abi3 Python >= 3.10 to dist-local\headroom_ai-0.29.0-cp310-abi3-win_amd64.whl

# Copied _core.pyd from the wheel into headroom/ for local route execution, then:
> python -m pytest tests/test_platform_stabilization_functional.py -q
collected 4 items
4 passed in 6.71s

> python -m pytest tests/test_install tests/test_cli/test_install_cli.py tests/test_platform_feature_matrix.py -q
collected 120 items
119 passed, 1 skipped in 17.16s

Commit hooks:
Sync plugin versions.....................................................Passed
check for merge conflicts................................................Passed
ruff.....................................................................Passed
ruff-format..............................................................Passed
mypy.....................................................................Passed
```

## Real Behavior Proof

- Environment: Windows 11, PowerShell, Python 3.13.13, worktree
`C:\git\headroom-stabilization` on branch
`jd/cross-platform-stabilization`.
- Exact command / steps: built the Windows wheel with `maturin`,
extracted `_core.pyd`, ran the new FastAPI route tests and
install/matrix tests listed above, then removed generated artifacts
before committing.
- Observed result: direct start paths now no-op when healthy, skip
spawning when the start lock is contended, and stop a wedged runtime
before restart. `/v1/compress` now returns original messages quickly on
timeout instead of a 503. The real JSON tool-payload smoke test returns
`tokens_before > tokens_after`, `tokens_saved > 0`, `compression_ratio <
1.0`, and non-empty transforms through the public route.
- Not tested: full native Windows persistent process e2e remains blocked
by the upstream CRT/wheel issue already documented in workflows and in
the matrix. No real OS service was installed locally; service manager
behavior is covered by argument-level unit tests.

## 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
- [ ] I have updated the CHANGELOG.md if applicable

## Screenshots (if applicable)

N/A

## Additional Notes

CHANGELOG is not updated because this is an unreleased
hardening/test/documentation pass. The platform matrix intentionally
records partial/blocked Windows/macOS e2e gaps instead of claiming full
coverage where the repo cannot currently run it.
2026-07-10 00:40:34 -04:00
.claude-plugin fix(release): sync all package versions to v0.31.0 (#1882) 2026-07-09 16:53:55 -05:00
.codegraph perf(compression): take large cold-start contexts off the synchronous kompress path (#1171) (#1298) 2026-06-23 10:48:06 -05:00
.devcontainer fix(transforms): use thread-local tree-sitter parsers to prevent pyo3 Unsendable panic (#604) 2026-06-10 18:30:00 -05:00
.github ci: allow PyPI deps during CPU torch install (#1930) 2026-07-09 19:36:26 -07:00
.serena feat: headroom wrap opencode / unwrap opencode CLI (#1105) 2026-06-22 11:07:12 -05:00
agent-evals fix(agent-evals): Phase 0 — coding-agent accuracy A/B framework (#1037) 2026-06-22 15:01:44 -05:00
benchmarks docs: sync README + benchmarks with code (drop retired IntelligentContext/RollingWindow) (#1545) 2026-06-28 22:36:41 -07:00
crates fix(adaptive-sizer): char bigrams for spaceless CJK items (#1748) 2026-07-09 17:01:29 -05:00
docker fix(dashboard): distinguish unavailable RTK from zero stats in Docker (#1901) 2026-07-09 09:39:16 -04:00
docs fix: harden persistent install startup (#1851) 2026-07-10 00:40:34 -04:00
e2e fix: use rtk native Cursor hook instead of injecting .cursorrules (#756) (#1846) 2026-07-07 23:31:54 -05:00
examples docs: sync README + benchmarks with code (drop retired IntelligentContext/RollingWindow) (#1545) 2026-06-28 22:36:41 -07:00
headroom fix: harden persistent install startup (#1851) 2026-07-10 00:40:34 -04:00
plugins deps: bump @types/node from 22.19.15 to 26.1.1 in /plugins/openclaw (#1685) 2026-07-09 17:02:22 -05:00
REALIGNMENT docs: add Realignment plan (40 PRs, 9 phases) 2026-05-01 23:34:46 -07:00
sbom fix(deps): remediate dependency CVEs and publish SBOM (#1509) 2026-06-27 15:28:12 -07:00
scripts ci: preserve merge labels while state is unknown 2026-07-09 19:51:41 -05:00
sdk/typescript chore: release main (#1918) 2026-07-09 07:47:54 -07:00
sql feat(telemetry): add headroom_stack and install_mode identity fields 2026-04-17 17:12:38 +02:00
tests fix: harden persistent install startup (#1851) 2026-07-10 00:40:34 -04:00
wiki feat(content-router): lossless-first dispatch, cross-turn dedup, and A7 lossy-after-fold (#1818) 2026-07-06 08:32:06 -07:00
.actrc feat: add act testing config, fix gitignore, make workflow production-ready 2026-04-15 20:28:29 -05:00
.actrc.local.example feat: add act testing config, fix gitignore, make workflow production-ready 2026-04-15 20:28:29 -05:00
.changelog.md fix: use /tmp for changelog artifact to avoid . file matching issues 2026-04-15 22:54:34 -05:00
.commitlintrc.json ci: fix smart_crusher branch CI failures + add make ci-precheck pre-push gate 2026-04-27 11:13:47 -07:00
.dockerignore fix(docker): report source build version (#1862) 2026-07-08 13:32:04 -05:00
.env.act.example feat: add act testing config, fix gitignore, make workflow production-ready 2026-04-15 20:28:29 -05:00
.env.example fix(security): patch loopback guard, retry None raise, blocking subprocess, and cache stats race 2026-06-04 16:09:53 -04:00
.git-blame-ignore-revs chore: add .git-blame-ignore-revs 2026-04-24 15:35:29 +02:00
.gitattributes chore: enforce LF checkout for Python files 2026-04-23 08:43:03 -05:00
.gitguardian.yaml fix: harden Copilot API auth token handling (#557) 2026-06-11 12:57:48 -05:00
.gitignore chore: remove committed node_modules + stray/internal markdown (repo hygiene) (#1528) 2026-06-27 23:32:54 -07:00
.gitleaks.toml fix(ci): extend gitleaks allowlist to cover test fixtures + verified examples (#1539) 2026-06-28 13:10:58 -07:00
.pre-commit-config.yaml ci: guard against committed merge-conflict markers (#1505) 2026-06-30 14:20:25 -05:00
.release-please-config.json ci(release-please): set versioned PR title pattern to fix tagging jam 2026-06-04 09:56:35 -07:00
.release-please-manifest.json chore: release main (#1918) 2026-07-09 07:47:54 -07:00
Cargo.lock deps: bump the cargo-minor-patch group across 1 directory with 7 updates (#1909) 2026-07-09 09:21:38 -04:00
Cargo.toml fix(deps): remediate dependency CVEs and publish SBOM (#1509) 2026-06-27 15:28:12 -07:00
CHANGELOG.md fix: emit unknown Anthropic content blocks verbatim in buffered-to-SSE conversion (#1825) 2026-07-09 21:45:40 -05:00
claude_analysis_ttl.py chore: add cache TTL cost analysis script 2026-05-13 10:49:17 -07:00
CODE_OF_CONDUCT.md chore(telemetry): remove Supabase anonymous beacon; fix contact domain to headroomlabs.ai (#1526) 2026-06-27 22:48:26 -07:00
codecov.yml fix(codex): poll /wham/usage for subscription limits (handshake no longer sends x-codex-* headers) (#924) 2026-06-12 17:03:14 -05:00
CONTRIBUTING.md fix(cli): harden all CLI surfaces + fix docs accuracy (#1491) 2026-06-27 14:48:43 -07:00
deny.toml feat(rust): scaffold workspace + parity harness (phase-0) 2026-04-24 13:39:48 -07:00
docker-bake.hcl refactor(docker): migrate to bake with multi-variant distroless images 2026-04-04 21:51:37 +05:30
docker-compose.yml fix(dashboard): distinguish unavailable RTK from zero stats in Docker (#1901) 2026-07-09 09:39:16 -04:00
Dockerfile fix(docker): report source build version (#1862) 2026-07-08 13:32:04 -05:00
Headroom-2.gif Add demo GIF to README 2026-01-20 18:57:17 -08:00
headroom-savings.png docs: rewrite README for clarity and highlight Kompress-base, leaderboard, RTK 2026-04-18 09:36:49 -07:00
headroom_learn.gif docs: add headroom learn demo GIF to README 2026-03-07 17:56:17 -08:00
HeadroomDemo-Fast.gif Replace demo GIF with HeadroomDemo-Fast.gif 2026-04-10 15:05:25 -07:00
LICENSE Prepare for OSS release v0.2.0 2026-01-07 11:36:44 -08:00
llms.txt fix(cli): harden all CLI surfaces + fix docs accuracy (#1491) 2026-06-27 14:48:43 -07:00
Makefile feat: headroom wrap opencode / unwrap opencode CLI (#1105) 2026-06-22 11:07:12 -05:00
mkdocs.yml feat: add Vertex AI proxy routing (#793) 2026-06-09 23:05:30 -07:00
NOTICE Prepare for OSS release v0.2.0 2026-01-07 11:36:44 -08:00
pyproject.toml fix: patch nltk vulnerability (CVE-2026-54293) (#1929) 2026-07-09 21:20:13 -07:00
README.md docs: retire IntelligentContext from README and installation guide (#1445) 2026-07-08 09:16:11 -05:00
rust-toolchain.toml fix(rust): clippy 1.95 unnecessary_sort_by + pin toolchain 2026-04-27 12:11:49 -07:00
RUST_DEV.md chore: remove committed node_modules + stray/internal markdown (repo hygiene) (#1528) 2026-06-27 23:32:54 -07:00
SECURITY.md chore(telemetry): remove Supabase anonymous beacon; fix contact domain to headroomlabs.ai (#1526) 2026-06-27 22:48:26 -07:00
TESTING-copilot-subscription.md fix(copilot): restore generic endpoint for non-subscription OAuth (#610) (#612) 2026-06-04 16:27:54 -07:00
uv.lock fix: patch nltk vulnerability (CVE-2026-54293) (#1929) 2026-07-09 21:20:13 -07:00

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              The context compression layer for AI agents

6095% fewer tokens (for JSON data), 15-20% fewer tokens (for coding agents) · library · proxy · MCP · content-aware compressors · local-first · reversible

CI codecov PyPI npm Model: Kompress-v2-base License: Apache 2.0 Docs

Docs · Install · Proof · Agents · Discord · llms.txt

AI agents / LLMs: read /llms.txt here, or fetch the live index / full docs blob.


chopratejas%2Fheadroom | Trendshift

Headroom compresses everything your AI agent reads — tool outputs, logs, RAG chunks, files, and conversation history — before it reaches the LLM. Same answers, fraction of the tokens.

Headroom in action
Live: 10,144 → 1,260 tokens — same FATAL found.

What it does

  • Librarycompress(messages) in Python or TypeScript, inline in any app
  • Proxyheadroom proxy --port 8787, zero code changes, any language
  • Agent wrapheadroom wrap claude|codex|copilot|cursor|aider|opencode|cline|continue|goose|openhands|openclaw|vibe in one command; undo with headroom unwrap <tool>
  • MCP serverheadroom_compress, headroom_retrieve, headroom_stats for any MCP client
  • Cross-agent memory — shared store across Claude, Codex, Gemini, auto-dedup
  • headroom learn — mines failed sessions, writes corrections to CLAUDE.local.md (default, gitignored) or CLAUDE.md / AGENTS.md / GEMINI.md
  • Output token reduction — trims what the model writes back (not just what you send): drops ceremony/restated code and skips deep "thinking" on routine steps. See Output token reduction.
  • Reversible (CCR) — originals are cached for retrieval on demand

How it works (30 seconds)

 Your agent / app
   (Claude Code, Cursor, Codex, LangChain, Agno, Strands, your own code…)
        │   prompts · tool outputs · logs · RAG results · files
        ▼
    ┌────────────────────────────────────────────────────┐
    │  Headroom   (runs locally — your data stays here)  │
    │  ────────────────────────────────────────────────  │
    │  CacheAligner  →  ContentRouter  →  CCR            │
    │                    ├─ SmartCrusher   (JSON)        │
    │                    ├─ CodeCompressor (AST)         │
    │                    └─ Kompress-v2-base (text, HF)  │
    │                                                    │
    │  Cross-agent memory  ·  headroom learn  ·  MCP     │
    └────────────────────────────────────────────────────┘
        │   compressed prompt  +  retrieval tool
        ▼
 LLM provider  (Anthropic · OpenAI · Bedrock · …)
  • ContentRouter — detects content type, selects the right compressor
  • SmartCrusher / CodeCompressor / Kompress-v2-base — compress JSON, AST, or prose
  • CacheAligner — stabilizes prefixes so provider KV caches actually hit
  • CCR — stores originals locally; LLM calls headroom_retrieve if it needs them

Architecture · CCR reversible compression · Kompress-v2-base model card

Get started (60 seconds)

# 1 — Install
uv tool install "headroom-ai[all]"      # Install `headroom` CLI as a global tool in self-contained virtual env
pip install "headroom-ai[all]"          # Python — ships the `headroom` CLI
npm install headroom-ai                 # TypeScript SDK only — no `headroom` CLI

# 2 — Pick your mode  (the `headroom` commands below come from the uv or pip install)
headroom wrap claude                    # wrap a coding agent
headroom proxy --port 8787              # drop-in proxy, zero code changes
# or: from headroom import compress      # inline library

# 3 — Verify setup and see the savings
headroom doctor                         # health check — confirms routing is working
headroom perf
headroom dashboard                      # live savings dashboard (proxy must be running)

To use headroom, it is recommended you launch a wrapped agent session each time so that all necessary setup is completed. When wrapping a coding agent, headroom starts a local proxy, sets up an MCP server that provides tools such as rtk and tokensave, and launches a coding agent session configured to proxy requests to headroom.

The headroom CLI ships only via the PyPI package. The npm headroom-ai is the TypeScript SDK — a library you import (import { compress } from 'headroom-ai'), not a CLI, so it provides no headroom command.

Granular extras: [proxy], [mcp], [ml], [code], [memory], [vector] (optional HNSW backend — needs a C++ toolchain, not in [all]), [relevance], [image], [agno], [langchain], [evals], [pytorch-mps] (Apple-GPU memory-embedder offload — set HEADROOM_EMBEDDER_RUNTIME=pytorch_mps). Requires Python 3.10+.

Codex / global install

If Codex or another MCP client cannot inherit a shell PATH reliably, install Headroom as a persistent uv tool and point the client at the absolute binary path:

uv tool install "headroom-ai[all]"
command -v headroom

Then use the returned path in MCP config:

[mcp_servers.headroom]
command = "/absolute/path/from/command-v/headroom"
args = ["mcp", "serve"]

command = "headroom" only works when the client starts with a PATH that already includes the uv tool directory.

Proof

Savings on real agent workloads:

Workload Before After Savings
Code search (100 results) 17,765 1,408 92%
SRE incident debugging 65,694 5,118 92%
GitHub issue triage 54,174 14,761 73%
Codebase exploration 78,502 41,254 47%

Accuracy preserved on standard benchmarks:

Benchmark Category N Baseline Headroom Delta
GSM8K Math 100 0.870 0.870 ±0.000
TruthfulQA Factual 100 0.530 0.560 +0.030
SQuAD v2 QA 100 97% 19% compression
BFCL Tools 100 97% 32% compression

Reproduce: python -m headroom.evals suite --tier 1 · Full benchmarks & methodology

Output token reduction (cut what the model writes back)

Everything above shrinks the prompt you send. But you also pay for every token the model writes back — and on Opus-class models output costs 5× input. A lot of that output is waste: "Great, let me…" preambles, re-printing code you just showed it, and deep "thinking" on routine steps like reading a file.

Headroom can trim that too, from the proxy, without you changing any code:

  • Verbosity steering — appends a short "be terse, don't restate context" note to the end of the system prompt (so your prompt cache still hits).
  • Effort routing — when a turn is just the model resuming after a tool result (a file read, a passing test), it dials the model's thinking effort down. New questions and errors keep full effort.

Turn it on:

export HEADROOM_OUTPUT_SHAPER=1     # off by default
headroom proxy --port 8787

Already running a proxy? These switches are read live on every request, so a proxy that headroom wrap reused (rather than started) would not see a value you export afterwards — its environment was snapshotted at launch. headroom wrap now hot-syncs your current settings to the running proxy via a loopback POST /admin/runtime-env, so they take effect immediately with no restart (no cold start, no dropped requests, no lost caches). Set them before you wrap. On a shared proxy these overrides are global — the last explicit setting wins.

Learn the right terseness for you. People don't say how terse they want answers — they show it (they interrupt long replies, or move on before they could have read them). headroom learn --verbosity reads your past sessions and picks the level automatically:

headroom learn --verbosity            # preview what it found (dry run)
headroom learn --verbosity --apply    # save it; the proxy uses it from now on

See how many output tokens you saved. Output savings are counterfactual — we never see what the model would have written — so Headroom reports an honest estimate with a confidence range, never a made-up number:

headroom output-savings
# Reduction: 31.7%  (95% CI 27.7% … 35.7%)   [estimated]

Want a measured number instead of an estimate? Leave 10% of conversations unshaped as a control group: export HEADROOM_OUTPUT_HOLDOUT=0.1. The dashboard shows an Output Tokens Saved card next to input compression, labelled measured or estimated with the confidence band.

→ Full write-up incl. the measurement methodology: Output token reduction

Star History Chart

Agent compatibility matrix

Agent headroom wrap Notes
Claude Code --memory · --code-graph · --1m · --tool-search
Codex shares memory with Claude
Cursor Manual setup starts proxy and prints base URLs for Cursor settings
Aider starts proxy + launches
Copilot CLI starts proxy + launches
OpenClaw installs as ContextEngine plugin
OpenCode injects config · starts proxy + launches
Cline starts proxy + injects config
Continue starts proxy + injects config
Goose starts proxy + launches
OpenHands starts proxy + launches
Mistral Vibe starts proxy + launches
Cortex Code Library only 6065% savings (library mode; no wrap)

Any OpenAI-compatible client works via headroom proxy. MCP-native: headroom mcp install. Undo durable wrapping with headroom unwrap <tool> (supports: claude, copilot, codex, opencode, openclaw).

GitHub Copilot CLI subscription mode

Headroom can route GitHub Copilot CLI subscription traffic through the local proxy:

headroom copilot-auth login
headroom wrap copilot --subscription -- --model gpt-4o

This lets Headroom intercept OpenAI-compatible Copilot CLI requests and apply the same proxy compression pipeline before forwarding to GitHub Copilot's hosted API. The wrapper exchanges Headroom's reusable GitHub OAuth token for Copilot's short-lived API token and prints the upstream endpoint as COPILOT_PROVIDER_API_URL=... during launch.

headroom copilot-auth login stores a Headroom-specific Copilot OAuth token. This avoids relying on generic GitHub or Copilot CLI tokens that can read Copilot account metadata but may still be rejected by Copilot's token-exchange endpoint.

For GitHub Enterprise Server or custom-domain Copilot deployments, set the deployment domain before launching:

export GITHUB_COPILOT_ENTERPRISE_DOMAIN=ghe.example.com

For GitHub.com Enterprise Cloud URLs such as github.com/enterprises/your-enterprise, do not set an enterprise-domain override. Headroom uses GitHub's normal token-exchange endpoint and the Copilot API endpoint advertised for the signed-in account.

Platform support note: macOS auth reuse via Copilot CLI Keychain storage has been smoke-tested. Windows Credential Manager, Linux Secret Service / secret-tool, and Docker/CI token-injection paths are implemented or planned as auth-discovery paths, but still need real OS validation before they should be considered fully vetted. For Docker and CI, prefer passing an explicit GITHUB_COPILOT_TOKEN or GITHUB_COPILOT_GITHUB_TOKEN rather than relying on host keychain access.

When to use · When to skip

Great fit if you…

  • run AI coding agents daily and want savings without changing your code
  • work across multiple agents and want shared memory
  • need reversible compression — originals are retrievable via CCR within the configured TTL

Skip it if you…

  • only use a single provider's native compaction and don't need cross-agent memory
  • work in a sandboxed environment where local processes can't run
Integrations — drop Headroom into any stack
Your setup Hook in with
Any Python app compress(messages, model=…)
Any TypeScript app await compress(messages, { model })
Anthropic / OpenAI SDK withHeadroom(new Anthropic()) · withHeadroom(new OpenAI())
Vercel AI SDK wrapLanguageModel({ model, middleware: headroomMiddleware() })
LiteLLM litellm.callbacks = [HeadroomCallback()]
LangChain HeadroomChatModel(your_llm)
Agno HeadroomAgnoModel(your_model)
Strands Strands guide
ASGI apps app.add_middleware(CompressionMiddleware)
Multi-agent SharedContext().put / .get
MCP clients headroom mcp install
What's inside
  • SmartCrusher — universal JSON: arrays of dicts, nested objects, mixed types.
  • CodeCompressor — AST-aware for Python, JS/TS, Go, Rust, Java, C/C++, Perl.
  • Kompress-v2-base — our HuggingFace model, trained on agentic traces.
  • Image compression — 4090% reduction via trained ML router.
  • CacheAligner — stabilizes prefixes so Anthropic/OpenAI KV caches actually hit.
  • Live-zone compression — compresses only new bytes (fresh tool output, latest turn); frozen prefix stays byte-identical so provider cache is not busted. History is never dropped.
  • CCR — reversible compression; LLM retrieves originals on demand.
  • Cross-agent memory — shared store, agent provenance, auto-dedup.
  • SharedContext — compressed context passing across multi-agent workflows.
  • headroom learn — plugin-based failure mining for Claude, Codex, Gemini.
Pipeline internals

Headroom exposes one stable request lifecycle across compress(), the SDK, and the proxy:

SetupPre-StartPost-StartInput ReceivedInput CachedInput RoutedInput CompressedInput RememberedPre-SendPost-SendResponse Received

  • Transforms do the work: CacheAligner → ContentRouter → SmartCrusher / CodeCompressor / Kompress-base (live-zone only; IntelligentContext and RollingWindow were retired in PR-B1).
  • Pipeline extensions observe or customize lifecycle stages via on_pipeline_event(...).
  • Compression hooks sit alongside the canonical lifecycle as an additional extension seam.
  • Proxy extensions remain the server/app integration seam for ASGI middleware, routes, and startup policy.

Provider and tool-specific behavior lives under headroom/providers/ so core orchestration stays focused on lifecycle, sequencing, and policy.

  • CLI/tool slices: headroom/providers/claude, copilot, codex, openclaw
  • Provider runtime slices: headroom/providers/claude, gemini, plus shared backend/runtime dispatch in headroom/providers/registry.py
  • Core files stay orchestration-first: wrap.py, client.py, cli/proxy.py, and proxy/server.py delegate provider-specific env shaping, API target normalization, backend selection, and transport dispatch.

Headroom for teams

Headroom OSS is built for individual developers: run headroom proxy or headroom wrap on your laptop and start cutting tokens in minutes — free, local-first, your data never leaves your machine.

Running it across a whole engineering org is a different job: a shared, always-on deployment; centralized config and version rollout; org-wide savings dashboards; SSO and access controls; air-gapped / VPC installs; and someone to call when it matters. That's what we help companies with — self-hosted with support, or fully managed.

If your team is spending real money on LLM tokens — Claude Code, Codex, Cursor, or agents running in CI — and you want those savings across everyone, not just one laptop:

→ Email hello@headroomlabs.ai with your stack and rough monthly LLM spend, and we'll help you roll Headroom out across your organization.

Everything in this repo stays open source (Apache 2.0). The managed offering is simply for teams that would rather have it deployed, supported, and scaled for them.

Install

pip install "headroom-ai[all]"          # Python, everything — includes the `headroom` CLI
npm install headroom-ai                 # TypeScript SDK (library only — no `headroom` CLI)
docker pull ghcr.io/chopratejas/headroom:latest

Granular extras: [proxy], [mcp], [ml] (Kompress-v2-base), [code], [memory], [vector] (optional HNSW backend — needs a C++ toolchain, not in [all]), [relevance], [image], [agno], [langchain], [evals], [pytorch-mps] (Apple-GPU memory-embedder offload — set HEADROOM_EMBEDDER_RUNTIME=pytorch_mps). Requires Python 3.10+.

Note

: [all] covers the core stack but excludes framework adapters. Install them separately: pip install "headroom-ai[langchain]" (also [agno], [strands], [anyllm], [bedrock]).

Using pipx? Choose a supported interpreter explicitly:

pipx install --python python3.13 "headroom-ai[all]"

Pick 3.13 if you want dollar savings. The dashboard's Proxy $ Saved tile prices compression with LiteLLM, and LiteLLM can't be installed on Python 3.14+. On 3.14 token savings still track, but the dollar figure stays $0.00. If you already installed on 3.14, switch with pipx reinstall headroom-ai --python python3.13 and restart the proxy.

Installation guide — Docker tags, persistent service, PowerShell, devcontainers.

CPU requirement (x86/x86_64): the ONNX-backed features — Magika content detection and embedding relevance — use a precompiled ONNX Runtime that needs AVX2. On x86 hosts without AVX2 (some Docker/QEMU setups and older cloud VMs) Headroom automatically falls back to its non-ONNX paths (BM25 relevance, heuristic detection) rather than crashing. arm64/Apple Silicon needs no AVX2.

Updating

headroom update          # detects pip / pipx / uv tool and upgrades in place
headroom update --check  # report the latest release without upgrading
headroom update --pre    # include pre-releases

headroom update figures out how Headroom was installed (pip/venv, pip --user, pipx, uv tool) and runs the matching upgrade across macOS, Linux, and Windows. For git checkouts, editable installs, Docker images, and externally-managed system Pythons (PEP 668) it prints the correct manual step instead of guessing.

The proxy also shows a one-line "update available" notice on startup. It checks PyPI at most once a day, in the background, and never blocks. Opt out with HEADROOM_UPDATE_CHECK=off (also skipped in --stateless mode and CI).

Corporate / SSL-inspection environments

If pip install "headroom-ai[all]" fails with CERTIFICATE_VERIFY_FAILED (unable to get local issuer certificate), your network uses SSL inspection — a MITM proxy presenting a company-issued CA. The build backend (maturin) downloads rustup over a connection your TLS stack doesn't trust. Install Rust first so the build doesn't fetch it:

# macOS / Linux
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh && rustup default stable
# Windows
winget install Rustlang.Rustup && rustup default stable

Restart your shell, then pip install "headroom-ai[all]". A prebuilt wheel avoids the Rust build entirely where available: pip install --only-binary headroom-ai headroom-ai. Prebuilt wheels are published for Windows (win_amd64), Linux (x86_64 / aarch64), and macOS (Apple Silicon and Intel), so installs on those platforms never need a local Rust toolchain — the Rust-first dance above is only for the platform-independent sdist fallback when no wheel matches.

Two runtime assets are fetched over TLS; if they are blocked, trust your corporate CA via REQUESTS_CA_BUNDLE / SSL_CERT_FILE / CURL_CA_BUNDLE:

  • cdn.pyke.io — the ONNX Runtime for the Rust core. Alternatively pre-provide it with ORT_STRATEGY=system and ORT_LIB_LOCATION=/path/to/onnxruntime.
  • huggingface.co — the kompress-base compression model. Pre-download it and run with HF_HUB_OFFLINE=1, or set HF_ENDPOINT to a trusted mirror.

Running with compression disabled (pure gateway) requires neither asset.

"Basic Constraints of CA cert not marked critical" (Python 3.13+ strict mode)

A different failure from the one above. If TLS fails with:

[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed:
Basic Constraints of CA cert not marked critical

then the corporate CA is found and trusted — adding it to a CA bundle changes nothing. Python 3.13 + OpenSSL 3.x enable VERIFY_X509_STRICT by default, which enforces RFC 5280 §4.2.1.9: a CA cert's basicConstraints must be marked critical. Inspection roots like Zscaler set CA:TRUE without the critical bit, so the chain is rejected.

Set HEADROOM_TLS_STRICT=0 to clear only the strict flag from every TLS context Headroom controls — the proxy's httpx upstream client and the urllib3/huggingface_hub path used for model downloads. Chain validation, signature, expiry, and hostname checks all stay on; this is strictly narrower than disabling verification.

HEADROOM_TLS_STRICT=0 headroom proxy --port 8787

The Rust core's ONNX download (cdn.pyke.io) uses a separate TLS stack (rustls / OS trust store), unaffected by HEADROOM_TLS_STRICT. On Windows the corporate root must be in the machine certificate store (browsers already trust it there); or pre-provision ONNX Runtime with ORT_STRATEGY=system + ORT_LIB_LOCATION=/path/to/onnxruntime to skip the download entirely.

headroom learn

headroom learn in action

headroom learn — mines failed sessions, writes corrections to CLAUDE.local.md (default, gitignored; use --target CLAUDE.md for the shared team file) / AGENTS.md / GEMINI.md.

Documentation

Start here Go deeper
Quickstart Architecture
Proxy How compression works
MCP tools CCR — reversible compression
Memory Cache optimization
Failure learning Benchmarks
Configuration Limitations
Persistent installs (headroom init / headroom install apply) Savings analytics (headroom savings / headroom perf / headroom doctor)

Compared to

Headroom runs locally, covers every content type, works with every major framework, and is reversible.

Scope Deploy Local Reversible
Headroom All context — tools, RAG, logs, files, history Proxy · library · middleware · MCP Yes Yes
RTK CLI command outputs CLI wrapper Yes No
lean-ctx Tool output, files, shell, history Proxy · library · middleware · MCP · CLI Yes Yes
Compresr, Token Co. Text sent to their API Hosted API call No No
OpenAI Compaction Conversation history Provider-native No No

Attribution. Headroom ships with the excellent RTK binary for shell-output rewriting — git show --short, scoped ls, summarized installers. Huge thanks to the RTK team; their tool is a first-class part of our stack, and Headroom compresses everything downstream of it. Headroom can also use lean-ctx as the selected CLI context tool; set HEADROOM_CONTEXT_TOOL=lean-ctx before running headroom wrap ....

Contributing

git clone https://github.com/chopratejas/headroom.git && cd headroom
uv sync --extra dev && uv run pytest

Devcontainers in .devcontainer/ (default + memory-stack with Qdrant & Neo4j). See CONTRIBUTING.md.

Community

License

Apache 2.0 — see LICENSE.