How do I install Phantom Secrets?

Copy the stdio config for Cursor, Claude Desktop, Claude Code, or VS Code on this page. It uses the publisher's install, not a PlugMCP proxy.

Does Phantom Secrets need an API key?

No required environment variable is listed on this record.

What transport does Phantom Secrets use?

Phantom Secrets runs locally over stdio.

When was Phantom Secrets last checked?

Last checked 2026-11-11. Value-blind secret metadata and gated workflows for AI coding agents through Phantom's local proxy.

Phantom Secrets MCP server

Your agent can use the key. It never sees it.

Delegate more to AI without putting real keys in agent context.

Phantom replaces project secrets with scoped phm_ placeholders. Applications use those placeholders through an authenticated local proxy, while agents use value-blind MCP tools for inventory, diagnostics, and governed requests.

Quick start · Delegate safely · Why Phantom? · MCP setup · Docs · Contribute · phm.dev

phantom init swaps the real keys in .env for phm_ tokens; phantom list shows the vault without values

Install

brew tap ashlrai/phantom
brew trust --formula ashlrai/phantom/phantom
brew install ashlrai/phantom/phantom

macOS via Homebrew; installs phantom and phantom-mcp (reviewed v0.7.8). Linux and Windows: use the matching release asset. Then run phantom init in your project and phantom setup --client claude (or cursor, windsurf, codex). Full walkthrough: Quick Start.

▶ Historical v0.4 demo — current behavior differs · 🛡 Security model · 📋 Threat model · 💬 Discussions

Start here

Choose the smallest path that answers your next question. The first path uses no credential, makes no network request, and does not install or configure Phantom.

Goal	Start	What it establishes
See the delegation boundary with no secret or setup	Run `node examples/first-five-minutes/run.mjs`, then read the first-five-minutes walkthrough	A deterministic, read-only example contract; not vault, proxy, provider, or deployment acceptance.
Protect a real local project	Follow Quick Start with the reviewed `v0.7.9` GitHub release	Local initialization and diagnostics on your machine.
Connect an AI coding client	Complete the first MCP task	Value-blind capability, status, and repository checks; no provider action.
Copy a tested client or CI setup	Run the Claude Code, Cursor, or GitHub Actions recipe (`node examples/<name>/run.mjs`)	Each recipe runs your `phantom` binaries (from `PATH` or `--phantom <path>`) in a temporary HOME with a fake, non-provider key and is exercised in CI.
Define a bounded task for an agent	Use the safe delegation quickstart	A reviewable task contract with explicit authority and acceptance boundaries.
Evaluate a team rollout	Use the enterprise adoption guide	A controlled evaluation plan; not a claim of commissioned cloud or enterprise service.
Audit the trust model first	Read the security model and threat model

Why Phantom?

AI coding agents routinely work in repositories that also contain local credentials. Once a real API key enters an agent context, transcript, tool call, or generated file, you have lost control of where that value may persist.

Traditional secrets managers focus on keys at rest and in transit. Phantom adds a boundary for agent context:

🔒 Reduces one credential-exposure path — managed project dotenv files contain sensitive phm_ mappings, MCP responses remain value-blind, and exact proxy routes inject their own configured authentication values. Unmanaged files, broader shell authority, and same-user processes remain in the threat model.
⚡ Fast local setup — after installing the reviewed v0.7.9 GitHub release, phantom init protects a project without requiring an account, DNS changes, or a custom CA.
🧰 Agent-native integrations — setup helpers and value-blind MCP workflows for Claude Code, Cursor, Windsurf, and Codex, plus project instructions for GitHub Copilot.
🦀 Open source, local-first, MIT — secrets use the native OS credential store when it is available, with an explicit encrypted-file fallback. Optional cloud sync encrypts vault payloads client-side before the server stores them.

Project status and trust boundary

Phantom's implemented user-facing surfaces are the CLI, vault, authenticated local proxy, MCP server, and optional cloud/team workflows documented below. Cloud and team behavior additionally depends on the deployed service, account plan, and provider configuration; source code alone is not deployment or customer-acceptance evidence. The conversation facade is intentionally narrow:

phantom_do is proposal-only. It canonicalizes a closed Cargo action and reports its digest, effect, and activation blockers; execute is hard denied.
phantom_setup_workspace can propose setup, create a bearerless request, and report authenticated status. Applying a request remains a separate trusted-terminal operation.
Advanced MCP tools remain a compatibility catalog, disabled by default, with separate explicit confirmation and informed terminal-approval gates. They are not governed by the conversation facade's capability card.
phantom grant retains value-blind lifecycle metadata and design-source foundations, but 0.7.9 hard-denies every live provider issuance/renewal path before credential or network access. A provider grant is not an execution-kernel authority grant, broker lease, or permission for an agent to execute work.
The authority, broker, runtime, session, and evidence crates are inactive, fail-closed foundations. They do not establish live Locus authority, broker credentials, execute agent actions, or produce externally trusted receipts today.

See the documentation map, architecture, security policy, and threat model for the evidence behind those boundaries.

Measured: leak rate on a scripted adversary

Reproduce with python3 eval/leak-rate/harness.py 5 (about 3 minutes, Linux, phantom 0.7.9; fake canary keys only, no paid keys). Method and limits: eval/leak-rate/README.md.

setup	in-boundary attacks that exposed a canary key
plain `.env`, no protection	210 of 450
after `phantom init`	0 of 450

450 = 30 attack techniques x 3 secrets x 5 runs (cat .env, printenv, /proc/self/environ, base64 and hex dumps, git add -f, ps eww, phantom reveal/export/exec, every MCP tool called with confirm=true, and a README prompt injection the scripted agent obeys). Per-technique table: eval/leak-rate/table.md.

What this does not show: it is a scripted worst case, not an LLM, so it measures where a key can appear, not how often a model goes looking. One out-of-scope case is reported separately: an unmanaged key file the developer never put in .env stays readable (15 of 15 in both setups). Same-user access to the OS keychain is outside the documented boundary and is not tested. Proxy use of a key on an allowed route is by design. One machine, no external audit.

Quick Start

Install both binaries from the reviewed v0.7.9 GitHub release. On macOS, the Homebrew formula is the shortest path; it currently installs the previous reviewed v0.7.8 binaries until the tap is bumped to v0.7.9:

$ brew tap ashlrai/phantom
$ brew trust --formula ashlrai/phantom/phantom
$ brew install ashlrai/phantom/phantom

For exact v0.7.9 on macOS, Linux, or Windows, use the matching release asset in Installation. Then protect and verify the project:

$ phantom init
# Auto-detects .env, .env.local, or .env in subdirectories
# Stores real secrets in the native credential store or encrypted vault,
# then rewrites .env with phantom tokens
# Auto-configures Claude Code MCP server if detected

$ phantom agent doctor
# One human-readable readiness check for AI-agent safety

$ phantom exec -- claude
# Authenticated proxy running on an ephemeral 127.0.0.1 port
# App/test processes use phantom tokens; agents use value-blind metadata

For a task contract you can hand to Claude Code, Codex, Cursor, Windsurf, or Copilot, use the safe delegation quickstart and the copyable policy and task templates. Teams evaluating a controlled rollout can start with the enterprise adoption guide.

Windows

The same core command surface is implemented for native Windows, with remaining native acceptance limits tracked in the platform matrix. Install the exact v0.7.9 Windows ZIP for your architecture from Installation, verify its published .sha256 sidecar, and place both executables on PATH. WSL is a separate Linux environment with its own filesystem and credential-store context.

For an explicitly supervised foreground proxy, run phantom start with stdin, stdout, and stderr each attached to a trusted terminal. Terminal attachment is an admission check, not proof of who controls a PTY. The CLI detects your shell and prints the matching env-var syntax; copy those exports into the terminal that launches the client, keep the owning terminal open, and press Ctrl-C there to stop. Detached --daemon mode and external process control are fail-closed until Phantom has a separately reviewed private cross-platform control channel. phantom stop only authenticates a legacy v0.7.3 .phantom.pid session to report migration guidance; v0.7.3 had no authenticated shutdown endpoint, so the new binary never kills that process or deletes its record. Stop it from its owning v0.7.3 terminal with Ctrl-C, or use the bounded recovery procedure in Troubleshooting. For reference:

PowerShell:

$env:OPENAI_BASE_URL = "http://127.0.0.1:PORT/openai/_phantom/TOKEN/"
$env:PHANTOM_PROXY_PORT = "PORT"
$env:PHANTOM_PROXY_TOKEN = "TOKEN"

cmd.exe:

set OPENAI_BASE_URL=http://127.0.0.1:PORT/openai/_phantom/TOKEN/
set PHANTOM_PROXY_PORT=PORT
set PHANTOM_PROXY_TOKEN=TOKEN

Git Bash / WSL: use the export X=Y syntax from the main quick-start.

Notes:

PHANTOM_PROXY_TOKEN is the proxy session authenticator. By default, phantom exec and phantom start include it in local *_BASE_URL values as /_phantom/TOKEN/ so unmodified SDKs work. Header-aware clients can set PHANTOM_PROXY_HEADER_AUTH_ONLY=1 and send x-phantom-proxy-token: $PHANTOM_PROXY_TOKEN instead.
If phantom.exe is blocked by Windows application-control policy, do not automatically remove Mark-of-the-Web. First verify the archive checksum and both binary identities against the release metadata. If local policy permits the verified binaries, a user may then remove the mark explicitly with PowerShell: Get-ChildItem "$env:USERPROFILE\.phantom-secrets\bin\*.exe" | Unblock-File.
The pre-commit hook installed by phantom init is a #!/bin/sh script. Native git from the command line invokes it via Git for Windows' bundled sh.exe, which is what the official Git for Windows installer ships. GUI clients (GitHub Desktop, some IDE integrations) may run with a stripped-down PATH that lacks sh.exe and silently skip the hook — for these, run commits from a terminal, or use phantom check --staged directly. CI is the durable safety net regardless.
The immutable v0.7.9 release contains x64 and ARM64 Windows ZIPs, and both native Windows rows passed the tag-bound release acceptance workflow. The archives are not Authenticode-signed; this receipt does not prove every enterprise application-control policy will accept them. See the platform support matrix.

How It Works

  .env file (AI read denied)       OS Keychain / Vault
  +--------------------------+      +---------------------+
  | OPENAI_API_KEY=phm_a7f3  | ---> | sk-real-secret-key  |
  | STRIPE_KEY=phm_c9d1...   |      | sk_live_real-key... |
  +--------------------------+      +---------------------+
           |                                 |
           v                                 v
  App / test process                Phantom Proxy (127.0.0.1)
  +--------------------------+      +------------------------------+
  | Loads phm_ tokens        |      | Intercepts HTTP requests     |
  | Agent gets MCP metadata  | ---> | Injects route-owned auth key |
  | Makes API calls to proxy |      | Forwards over TLS to real API|
  +--------------------------+      +------------------------------+

phantom init reads .env, stores real secrets in the native OS credential store or encrypted-file fallback, and rewrites .env with phm_ tokens
phantom exec -- claude starts a local reverse proxy, sets SDK-compatible service base URLs such as OPENAI_BASE_URL=http://127.0.0.1:PORT/openai/_phantom/TOKEN/, exposes PHANTOM_PROXY_TOKEN to the child process, and launches the command
API calls hit the proxy, which authenticates the local session, removes its local auth token, injects only the matched route's vault value into that route's exact configured authentication header, and forwards over TLS. Client-controlled headers and bodies never resolve phm_ tokens.
When the session ends, the proxy shuts down and its bearer is invalid. phantom exec also replaces project tokens with fresh child-process tokens for that run. Project phm_ values persist until rotation; they are not provider credentials and are never client-resolved, but a process controlling an authenticated active proxy can still invoke its configured provider routes.

Phantom does not grant AI tools permission to read .env or other dotenv files. phantom setup removes legacy Phantom-managed dotenv read grants and preserves deny rules; agents use value-blind MCP inventory instead.

Provider grants

phantom grant retains value-blind lifecycle metadata and provider protocol design foundations. In 0.7.9, all live provider issuance, enrollment exchange, refresh, renewal, and revocation execution is hard-denied before Phantom reads a provider credential or opens a provider network connection. Do not use grant or rotation commands expecting a vendor-side change. Test-only mocks demonstrate local transaction behavior only; they are not live-provider acceptance.

In these docs, provider grant means design-era credential lifecycle metadata; no live grant flow runs in 0.7.9. Authority grant means the inactive, value-free execution authority type in phantom-authority. A provider grant cannot be reinterpreted as an authority grant, Locus credential, broker lease, or execution permit. See the design-era grant lifecycle specification; the issuance contract is the original design contract and retains design-era status language.

MCP Integration (Claude Code, Cursor, Windsurf, Codex)

Phantom ships an MCP server so AI coding tools can inspect value-blind metadata and request gated lifecycle operations. MCP responses do not return real secret values.

First MCP task: verify the boundary

Use this read-only path before exploring the full tool catalog:

Install both binaries from the reviewed v0.7.9 GitHub release.
From the project you want to inspect, run phantom setup --client codex, replacing codex with claude, cursor, or windsurf when appropriate.
Restart the AI client so it loads the generated MCP configuration.
Ask the client: “Call phantom_capability, then phantom_status. Report the value-blind authority, hard denials, project ID, dotenv protection counts, and service mappings. Do not request or reveal secret values.”
Ask the client: “Call phantom_check with no arguments. Report findings without changing files or credentials.”

These calls inspect the configured local surface. They do not prove that cloud, team, deployment, provider, authority-kernel, or customer workflows are active or accepted.

Conversation facade — phantom_capability reports authority and hard denials for the small facade (not the separately gated advanced compatibility catalog); phantom_do canonicalizes one closed Cargo action and reports the exact activation blockers without executing it; phantom_setup_workspace proposes an exact value-blind plan, creates a bearerless apply request after revalidation, or reads authenticated request status. Provisioning the machine-local seal key and creating a request both require confirm plus an out-of-band approval token; MCP never claims or applies the request.
Vault — phantom_list_secrets, phantom_status, phantom_init, phantom_add_secret_interactive, phantom_add_secret (deprecated; refuses plaintext), phantom_remove_secret, phantom_rotate, phantom_copy_secret
Detection + diagnostics — phantom_doctor, phantom_why, phantom_check, phantom_env, phantom_validate_secret, phantom_validate_all
Local-to-cloud — phantom_wrap, phantom_unwrap, phantom_sync, phantom_cloud_push, phantom_cloud_pull, phantom_cloud_status
Teams — phantom_team_list, phantom_team_create, phantom_team_members, phantom_team_invite, phantom_team_key_publish, phantom_team_vault_push, phantom_team_vault_pull
Advanced audit, rotation, expiry, and compliance — phantom_audit_recent, phantom_audit_stats, phantom_audit_analytics, phantom_audit_anomalies, phantom_audit_anomalies_realtime, phantom_audit_hotspot_alerts, phantom_audit_incidents, phantom_leak_incidents_realtime, phantom_audit_alerts, phantom_audit_export_report, phantom_compliance_status, phantom_rotate_with_candidate, phantom_rotate_promote, phantom_rotate_provider, phantom_rotate_with_expiry, phantom_list_with_expiry, phantom_secret_rotation_due, , , , , , ,

phantom_secrets_auto_rotate and phantom_rotate_with_expiry are deprecated compatibility names for approved local phm_ token remaps. They do not rotate a provider credential, renew TTL/rotated_at metadata, clear leak incidents, or sync credentials. phantom_rotate_provider is also hard-denied before credential or network access in 0.7.9. Team invites may assign only member or admin; ownership transfer is not an invite role.

Tools that write state, retrieve or use credentials, or make provider/network requests are disabled by default. They can reach their confirm: true and one-use approval_token gates only when the operator sets PHANTOM_MCP_EFFECTS=trusted-terminal in a server environment outside agent authority. phantom mcp-approve requires attached stdin/stderr, shows the bounded value-blind effect plus exact parameters, and requires a fresh typed challenge before approval. A same-user shell or agent-controlled PTY can defeat that ceremony; leave effects disabled unless the approval command and ~/.phantom approval storage are outside the requesting agent's authority. Conditional tools keep their inspection mode ungated and activate both gates only for the effectful parameters. Real secret values are never accepted as MCP tool arguments; new secrets are entered out-of-band in a trusted terminal. The exact 54-tool names, descriptions, and JSON schemas are mirrored from runtime tools/list into mcp-registry/server.json, and release smoke tests reject any drift.

phantom_rotate_with_candidate and phantom_rotate_promote remain in the 54-tool compatibility catalog as deprecated hard denials. They never create, validate, or promote a candidate and never change vault or shadow metadata; phantom_rotate_provider is also hard-denied before credential or network access in 0.7.9. phantom add creates new names only and refuses existing-name replacement before reading a value. Replacing a credential therefore requires a separately reviewed provider rotation plus an explicit trusted-terminal remove-and-add sequence; those are distinct, non-atomic operations.

Workspace setup is deliberately split across trust boundaries. MCP can call phantom_setup_workspace with phase=propose, then phase=request_apply using the exact returned plan_id and pre_state_id. The first proposal requires dual approval only when it must provision the machine-local plan-seal key; request_apply always requires dual approval because it persists a value-free request outside the repository. Apply it from an attached trusted terminal with phantom workspace apply --request <ID>; MCP has no claim or apply operation.

One command per AI client — Phantom writes the right config file in the right place:

phantom setup --client claude     # project MCP; see docs/claude-code.md for v0.7.9 migration
phantom setup --client cursor     # ~/.cursor/mcp.json
phantom setup --client windsurf   # ~/.codeium/windsurf/mcp_config.json
phantom setup --client codex      # ~/.codex/config.toml
phantom setup --client gemini     # ~/.gemini/settings.json (Gemini CLI)
phantom setup --client claude --print   # snippet to stdout for any other client

Install both v0.7.9 release binaries before setup. Version 0.7.9 records the running phantom executable with mcp serve when it can resolve that executable, otherwise it looks for a local standalone phantom-mcp. Setup has no network package-runner fallback and fails closed when neither local runtime is executable. Inspect the generated entry, then restart the AI tool so it picks up the new config.

Phantom's stdio MCP server can be configured in MCP clients that support local command servers. The setup writer currently has reviewed presets for Claude Code, Cursor, Windsurf, Codex, and Gemini CLI; other clients require their own compatible configuration.

Cloud backup + Dashboard

Back up and restore a vault on the same keychain machine with client-side encryption. Phantom Cloud receives the encrypted vault payload rather than the decrypted secret values; endpoint, client, account, and OS-keychain security remain part of the trust boundary. The cloud encryption key is generated and stored in the local OS keychain. Phantom does not currently ship key transfer or recovery, so account sign-in without that key cannot decrypt this backup. Login, logout, cloud push/pull, and browser open are not headless agent actions: run them with stdin, stdout, and stderr attached to a terminal outside the requesting agent's authority and complete each fresh exact typed challenge. The public hosted service is not currently commissioned for authenticated cloud or dashboard use. The commands below document the source-backed flow for a future verified deployment and entitled account; they are not a live-service acceptance receipt.

$ phantom login
# Opens GitHub OAuth (device code flow)

$ phantom cloud push
# After commissioning: encrypted client-side and uploaded to the configured service

$ phantom cloud pull   # restore on the machine that holds the original cloud key
# Downloaded and decrypted locally

$ phantom open
# After commissioning: opens the configured read-only dashboard.

Cloud backup uses ChaCha20-Poly1305 with a random client-side passphrase stored in the OS keychain and derived via Argon2id for encryption. The server stores only ciphertext. Team vaults are separate: they wrap a shared vault key to each registered member's X25519 public key; that does not make personal cloud backups portable.

Team vaults (source-backed pilot)

The repository includes fixed-membership team-vault workflows intended for a planned hosted Pro pilot. Pilot eligibility, team and vault limits, and pricing are TBD; no self-serve checkout is commissioned. The service path stores ciphertext plus per-member encrypted key shares. Team roles gate invitation management, but all members can read and write the shared vault; member removal and atomic offboarding rotation are not shipped. Treat this as a pilot capability until the hosted service and account entitlement are commissioned. CLI team mutations require the same attached trusted-terminal ceremony before credential, keypair, vault-value, or network access. MCP team reads and writes are provider requests and remain disabled by default behind confirm plus a one-use out-of-band approval token.

$ phantom team create "engineering"
# Creates a team; you become the owner.

$ phantom team invite <team_id> <github-username>
# Invites by GitHub login.

$ phantom team key-publish <team_id>
# Registers your X25519 public key on the team.
# (Run once per team; the private key stays in the OS keychain.)

$ phantom team vault-push <team_id>
# Encrypts the current project's vault with a fresh symmetric key,
# wraps that key (X25519 + ChaCha20-Poly1305) for every member that
# has a registered public key, then uploads.

$ phantom team vault-pull <team_id>   # on a teammate's machine
# Pulls, decrypts the per-member share with their private key,
# decrypts the vault, writes secrets locally.

Experimental: X-Wing hybrid team share

The pq-hybrid cargo feature adds an experimental X-Wing (X25519 + ML-KEM-768) team key share. It is off by default and does not change default behavior: the default build keeps the X25519 share described above. The X-Wing share is local only. phm.dev does not accept it yet, because the hosted team key route takes 32-byte public keys and an X-Wing public key is 1216 bytes. The x-wing and ml-kem crates are unaudited, and X-Wing is pre-1.0. Do not rely on it for production secrets.

Proxy upstream TLS key exchange

The proxy's HTTPS client uses the aws-lc-rs provider and offers the hybrid X25519MLKEM768 group first, then X25519, secp256r1 and secp384r1. A hybrid key exchange is used only if the upstream server supports it. A hermetic test confirms that a local server accepting only X25519MLKEM768 negotiates it with the proxy, and that a server sharing no group with the proxy fails the handshake. Which group a given provider negotiates is not tested. To see the groups this build offers, read from the proxy's own TLS config:

phantom doctor --pq

After a hosted deployment is commissioned and accepted, its read-only team dashboard is designed to show team memberships and member lists.

Command Reference

Command	Description
`phantom init`	Import `.env` secrets into vault and rewrite with phantom tokens. Use `--empty` to initialize a new project before its first `phantom add`; `add` does not auto-create project state. `--all <DIR>` processes eligible repositories found by the bounded five-level scan; discovery stops below the first matching repository. Use `--dry-run` to inspect the exact set and `--jobs N` / `-j N` to control parallelism. An existing `.env.example` is left unchanged.
`phantom exec -- <cmd>`	Start an authenticated proxy and run a command with secret injection
`phantom start`	Run an explicitly supervised foreground proxy; keep its trusted terminal open and press Ctrl-C there to stop
`phantom start --daemon` / `phantom stop`	Detached start fails closed; stop is a TTY-only legacy-state diagnostic that never kills or deletes, not current process control
`phantom list`	Show secret names stored in vault (never values; `--json` for machine-readable output)
`phantom add <KEY>`	Create a new secret name transactionally in an initialized project through a hidden terminal prompt or trusted `--stdin` producer; existing names are denied before any value read and are never replaced
`phantom remove <KEY>`	After exact trusted-terminal confirmation, transactionally remove the vault value, lifecycle config, and exact managed-dotenv mapping; headless use fails before value access or mutation
`phantom reveal <KEY>`	From an attached trusted terminal, review and type the exact challenge before printing one value or copying it for an auto-cleared 30-second clipboard window
`phantom status`	Show vault/mapping state and whether the machine-local lifecycle lock is held; a held lock does not authenticate or identify a listener
`phantom rotate`	After an exact attached-terminal challenge bound to the project, config, managed dotenv, and sorted protected-name digest, regenerate every local phantom token (old mappings become invalid). Headless use fails before vault access or mutation. Provider-backed / execution is hard-denied before credential or network access in 0.7.9.

Rotating real provider credentials

Phantom 0.7.9 does not execute live provider issuance or rotation. Every provider path—single-provider CLI, batch CLI, MCP, grant enrollment, additive issuance, and destructive/rolling refresh—is hard-denied before provider credential access and before network I/O. Operators must rotate at the vendor, then use Phantom's trusted local secret-entry path. Source adapters and exact cfg(test) mocks are transaction-design evidence, not provider activation, commissioning, or acceptance.

Provider support matrix

Provider	Support	Notes
`vercel`	Hard denied	Additive issuance can orphan a live successor after a local failure; no provider call in 0.7.9
`google`	Hard denied	Secret Manager version creation remains disabled pending durable successor recovery and verified abort
`github`	Hard denied	GitHub App installation-token issuance remains disabled pending the same recovery contract
`stripe`	Hard denied	Raw keys are manual; rolling OAuth refresh can invalidate the predecessor before successor recovery
`aws`	Hard denied	SigV4 access-key-pair rotation is not implemented
`sentry`	Hard denied	Installation-token issuance remains disabled pending durable successor recovery
`supabase`	Hard denied	PAT rotation is manual; OAuth/additive issuance paths are not commissioned

phantom rotate --batch remains metadata-only discovery/manual guidance and fails closed before vendor execution. No single-provider exception exists.

Features

Encrypted vault -- macOS Keychain, Linux keyutils by default, or Windows Credential Manager, with a ChaCha20-Poly1305 encrypted-file fallback for CI and headless environments. Linux keyutils entries do not survive a reboot; a headed Linux project can run phantom vault migrate-linux from a trusted terminal to copy and verify its vault in persistent Secret Service before switching. Phantom does not claim Secure Enclave hardware binding. Argon2id uses m=64 MiB, t=3, p=1.
Phantom tokens -- 256-bit CSPRNG phm_ placeholders in .env, rotatable on demand
Authenticated proxy sessions -- each proxy run generates a fresh PHANTOM_PROXY_TOKEN; CLI-generated SDK URLs include it for compatibility, and header-aware clients can opt into x-phantom-proxy-token with PHANTOM_PROXY_HEADER_AUTH_ONLY=1
Route-owned credential injection -- Client headers and bodies never resolve phm_ tokens. After authenticating and matching an exact built-in route, the proxy injects that route's configured vault secret only into its fixed authentication header; a missing mapping fails before any upstream call. Request bodies are still collected under a hard byte cap before forwarding. Custom routes: phantom start serves custom routes from .phantom.toml; phantom exec refuses them and runs only Phantom's exact built-in routes. The reason: phantom start is run by a person on project config they have reviewed. phantom exec launches an agent, and anything in the repository, .phantom.toml included, may have been written by that agent or by an untrusted change, so accepting custom routes there would widen the attack surface.
Full SSE/streaming support -- Response streaming preserved end-to-end for OpenAI, Anthropic, and other streaming APIs
Smart detection -- Heuristic engine distinguishes secrets (*_KEY, *_TOKEN, sk-*, ghp_*) from config (NODE_ENV, PORT)
Platform sync -- Push/pull secrets to Vercel and Railway
Pre-commit hook -- Runs phantom check --staged when Git invokes the hook; it checks staged dotenv content plus a bounded set of hardcoded-key prefixes. Hooks can be bypassed or skipped, so CI and a broader secret scanner remain necessary.
MCP server -- value-blind vault, diagnostics, cloud, team, audit, rotation, validation, expiry, and compliance responses for Claude Code, Cursor, Windsurf, and Codex; effectful compatibility tools remain separately gated and disabled by default

Installation

Homebrew (macOS; formula currently at v0.7.8)

Homebrew 6 requires explicit formula trust for third-party taps:

$ brew tap ashlrai/phantom
$ brew trust --formula ashlrai/phantom/phantom
$ brew install ashlrai/phantom/phantom

This formula installs both phantom and phantom-mcp from the immutable v0.7.8 GitHub release. It has not yet been bumped to v0.7.9. Until it is, a Homebrew install writes Claude Code MCP registration to the legacy location; see the Claude Code guide for the manual .mcp.json step, or use the v0.7.9 assets below.

Exact v0.7.9 GitHub assets

Use the asset matching your OS and architecture. Download its adjacent .sha256 file from the release, verify it before extraction, and place both phantom and phantom-mcp (.exe on Windows) on PATH.

Platform	`v0.7.9` archive	Published checksum
macOS Apple Silicon	`phantom-aarch64-apple-darwin.tar.gz`	`sha256`
macOS Intel	`phantom-x86_64-apple-darwin.tar.gz`	`sha256`
Linux x86_64	`phantom-x86_64-unknown-linux-gnu.tar.gz`	`sha256`
Linux ARM64	`phantom-aarch64-unknown-linux-gnu.tar.gz`	`sha256`
Windows x64	`phantom-x86_64-pc-windows-msvc.zip`	`sha256`
Windows ARM64	`phantom-aarch64-pc-windows-msvc.zip`

On Linux, verify with sha256sum -c <archive>.sha256. On Windows, compare Get-FileHash -Algorithm SHA256 <archive> with the published sidecar.

Build the exact release source

The v0.7.9 tag resolves to source commit 7a51ce512ec4aee12cc29ff859036af63fbe93db:

$ git clone https://github.com/ashlrai/phantom-secrets.git
$ cd phantom-secrets
$ git checkout 7a51ce512ec4aee12cc29ff859036af63fbe93db
$ cargo build --release --locked --bin phantom --bin phantom-mcp

Do not treat unpinned package-manager commands as v0.7.9. In the exact 2026-09-29 registry snapshot, npm latest remains 0.6.0; the immutable npm 0.7.4 wrappers exist only under release-candidate after failing cross-platform acceptance. No npm 0.7.9, crates.io 0.7.9, or MCP Registry 0.7.9 publication is represented by this GitHub release receipt. Homebrew is separately published and verified through its tap, and currently remains at v0.7.8.

Release-state snapshot

[!IMPORTANT] Release-state snapshot (verified 2026-09-29): the current release is the immutable v0.7.9 GitHub release at source commit 7a51ce512ec4aee12cc29ff859036af63fbe93db. Its 19-asset release set, checksums, archive-specific SPDX SBOMs, GitHub provenance and SBOM attestations, and all six native release rows are bound to that immutable release record by tag-bound workflow 34153902556. Exact public registry endpoints were requeried on 2026-09-29. The Homebrew formula still installs the previous reviewed v0.7.8 until its tap is bumped; npm latest remains 0.6.0, and the npm 0.7.4 wrappers remain quarantined under release-candidate after failed npm-channel acceptance. The GitHub receipt alone does not prove the separately verified Homebrew formula, an npm or crates.io package, MCP Registry entry, hosted-service commissioning, provider activation, signing/notarization, certification, or customer acceptance. See release readiness and platform support.

Connect an MCP client

$ phantom setup --client claude   # or cursor, windsurf, codex, gemini

Architecture

The Rust workspace is organized as product crates plus fail-closed execution-kernel foundations. Presence in the workspace does not mean a foundation is activated in production.

Layer	Crate	Role and current status
Product	`phantom-core`	Config, dotenv parsing/rewriting, tokens, auth, cloud client, audit, validation, and shared policy.
Product	`phantom-vault`	`VaultBackend` trait, OS keychain and encrypted-file backends, and shared cryptography.
Product	`phantom-proxy`	Authenticated loopback reverse proxy with fixed route-owned auth-header injection, inert client tokens, response scrubbing, and streaming support.
Product	`phantom-cli`	Operator CLI for initialization, proxy lifecycle, readiness, audit, import/export, sync, team, and workspace workflows.
Product	`phantom-mcp`	Stdio MCP server. The governed conversation facade is narrow; the advanced compatibility catalog uses separate legacy gates.
Product	`phantom-core/src/issuance`, CLI `grant`	Provider protocol/design foundations and value-free grant metadata. All live provider issuance/enrollment execution is hard-denied before credential or network access in 0.7.9.
Local effect layer	`phantom-core::fs`, `phantom-vault` transactions	Retained project/config directory capabilities, exact identity/content/permission before-images, no-follow targets, single-link checks, and typed durable, committed-verified-with-durability-warning, or `CommittedButUncertain` (Partial) effects.
Setup kernel	`phantom-workspace`	Value-blind discovery, sealed planning, and recoverable trusted-terminal setup transactions. Non-Unix durable mutation fails closed.
Inactive foundation	`phantom-authority`	Closed authority contracts and deny-all production verification boundary. No live Locus verifier.
Inactive foundation	`phantom-locus-contract`	Value-free compatibility contract describing requirements for a future Phantom/Locus integration.
Inactive foundation	`phantom-broker`	Bounded broker protocol and durable replay/accounting primitives. No active transport, lease issuer, or runtime connection.

Project-local effects resolve from the retained root acquired with the project transaction lock; global editor configuration is separately bounded beneath a retained user-config authority. A renamed ambient path and replacement decoy do not redirect those in-progress governed writes. These controls are not a same-user sandbox: local locks coordinate Phantom writers, and another process with equivalent user authority remains inside the threat model. See the architecture, threat model, and platform evidence matrix.

Initialization retains the reviewed project-root identity and exact dotenv/config leaf snapshots before vault provisioning, then revalidates root and leaf identity, bytes, and permissions under the project lock before mutation. On Windows, new private anchored files/directories establish a protected current-user DACL before content bytes, while replacements preserve the reviewed exact DACL and inheritance state before writing. Those Windows properties are source contracts; protected native Windows CI acceptance remains pending.

CommittedVerifiedButDurabilityUncertain is committed, exactly verified success with a value-free warning/receipt and must not be rolled back or retried. CommittedButUncertain is the distinct Partial case requiring operator reconciliation because verification or durability remains unresolved.

Vault-backed mutations resolve machine-local vault/application authority before the project transaction lock, then compare the acquired root identity and reread the exact config through that lock. This avoids the shared process-environment/project-lock inversion without trusting project bytes during the gap.

Phantom also tracks a pinned Rama-derived engineering standard for explicit network stacks, modular crates, runnable examples, and tiered platform CI. Rama is a benchmark, not a dependency, and the comparison is not a feature or platform-parity claim.

apps/web contains the Next.js site and backend routes for cloud vault sync, GitHub device authentication, and Stripe billing. The repository source and local tests are separate evidence from the currently deployed state at phm.dev.

Registry tracks: npm latest currently resolves phantom-secrets and phantom-secrets-mcp at 0.6.0. Exact 0.7.4 wrappers remain public only under release-candidate after failing native npm-channel acceptance; do not use that candidate as the reviewed v0.7.9 GitHub release path.

CI runs locked, all-target workspace builds and tests on macOS, Linux, and Windows runner environments, plus formatting, Clippy, and npm release-mapping checks. Release builds and native end-to-end acceptance are separate evidence layers; see Platform support.

Security

Managed dotenv replacement -- after successful initialization, Phantom-managed dotenv values are tokens; unmanaged files, backups, logs, and external tools remain outside this claim
ChaCha20-Poly1305 encryption for file vault and cloud sync, Argon2id key derivation
Client-encrypted cloud vaults -- the cloud vault API stores ciphertext; decryption happens in the authenticated client. This claim does not cover plaintext sent intentionally to deployment providers during phantom sync.
256-bit CSPRNG tokens -- phm_ prefix distinguishes Phantom tokens from supported real-key formats; random collisions are cryptographically negligible, not mathematically impossible
Proxy binds 127.0.0.1 only -- not bound to a non-loopback interface; same-user local-process and bearer theft remain in the threat model
Targeted memory zeroization for major vault retrieval, serialization, and decrypted-file buffers; some proxy lookup copies remain ordinary strings, so zeroization is defense in depth rather than a complete memory-erasure guarantee
Allowlist model -- proxy only injects secrets for explicitly configured service patterns

See SECURITY.md for the responsible disclosure policy and THREAT_MODEL.md for the full threat model (assets, actors, mitigations, known gaps, cryptography summary).

Open source and commercial offerings

Current offering	What it covers	Commercial boundary
Open source ($0)	Use, modify, and distribute the local CLI, vault, proxy, MCP server, and deployment-sync workflows under MIT	No hosted entitlement or support commitment is included
Enterprise (written scope)	Reversible evaluation, environment-specific integration, security review, and support terms	Scope, deliverables, price, schedule, and acceptance are defined in a separate agreement
Government (written scope)	Bounded public-sector evaluation and integration in a named non-production environment	No authorization, certification, contract vehicle, procurement schedule, hosted service, or SLA is represented

A Pro hosted pilot remains roadmap direction only. It is not a current public offering, has no commissioned self-serve checkout, and has no published price or entitlement. See the enterprise adoption guide for shipped-versus-planned gates, or contact [email protected] to discuss a written scope.

Part of the Ashlr ecosystem

Phantom Secrets is one of the open-source tools from Ashlr, a forward-deployed engineering company. Its siblings: Lexicon, Locus, Ashlr Stack, Ashlr Markdown, Ashlr plugin.

Contributing

Focused contributions are welcome. Start with CONTRIBUTING.md, the examples index, or a discussion. The project does not assume that a good first issue label is populated. Follow CODE_OF_CONDUCT.md, and use SECURITY.md rather than a public issue for vulnerabilities.

Star history

License

MIT — see LICENSE.