# Installation and setup REA separates installing its CLI from configuring external software and agents. ## Start setup Start setup with: ```bash npx rea-agents setup ``` If npm asks to download and run REA, that approval applies only to downloading the package. REA shows its own plan and asks before changing agent configuration or installing Hopper. The short command can use a REA version installed in the current project. To request the latest release explicitly, use: ```bash npx rea-agents@latest setup ``` REA runs the version npm selects. To update older agent registrations, run the latest-version command and review its setup plan. For unattended package downloads, add `--yes` before the package name; this does not approve REA's setup changes. For an intentional rollback, make the package request explicit: ```bash npm exec --yes --package=rea-agents@2.4.0 -- rea setup ``` Setup continues to pin persistent MCP registrations to the exact version that performed setup. Running current setup later migrates unversioned or older managed registrations through the normal reviewed setup transaction. REA supports Node.js 22.19+ and 24.11+ (including newer releases). It uses the npm already paired with that runtime and never upgrades Node.js, npm, or Homebrew. Running `npm install rea-agents` without `--global` installs the executable only in the current project's `node_modules/.bin`; it does not make `rea` available on the shell `PATH`. Use the setup command above for the guided setup journey, `npx -y rea-agents@latest` for unattended one-off commands, or install globally with `npm install --global rea-agents` for a shell-visible `rea` command. The optional curl wrapper installs only the global npm package: ```bash curl -fsSL https://raw.githubusercontent.com/morluto/rea/main/install.sh | bash ``` It prints the version, runtime, npm command, and destination before installing. When a controlling terminal exists it starts `rea setup`; otherwise it prints the command to run later. Pass options with `bash -s --`: ```bash curl -fsSL https://raw.githubusercontent.com/morluto/rea/main/install.sh | bash -s -- --dry-run ``` Supported options are `--version `, `--dry-run`, `--no-setup`, `--no-prompt`, and `--verbose`. Neither `--no-prompt` nor a non-interactive shell grants permission to install external dependencies. ## Supported agents Setup can configure these clients for REA's local MCP server: | Client | `--client` value | | ------------------ | ---------------- | | Claude Code | `claude_code` | | Claude Desktop | `claude_desktop` | | Codex | `codex` | | Cursor | `cursor` | | Gemini CLI | `gemini_cli` | | Windsurf | `windsurf` | | Devin | `devin` | | OpenCode | `opencode` | | Antigravity | `antigravity` | | GitHub Copilot CLI | `copilot_cli` | | VS Code | `vscode` | ## Review setup changes `rea setup` first offers the supported agents in a multi-select. Existing REA registrations are selected by default. Newly detected clients remain available but unselected: detection gives setup context, not permission to add a new registration. Clients without a detected configuration can still be selected. Explicit `--client` flags skip this question. Setup adds MCP access for selected clients. It installs REA's bundled workflow with those integrations by default; use `--skill=false` to omit it. If no agent is selected, setup offers the workflow separately for CLI use, with No as the default. Hopper is a separate optional choice: setup shows its proposed installation or connection and requires its own explicit approval. It can also save verified paths for an existing Ghidra installation. After selection, review the plan's exact paths and changes and approve before REA writes files or installs Hopper. You can cancel at any prompt. Before applying changes, REA checks your current configuration. The plan lists: - an existing Hopper installation, a verified existing Ghidra installation, or the official Hopper package it proposes to install; - each detected agent configuration path; - the REA skill destination; - external software, network origins, integrity evidence, and package-manager commands. Malformed or unsafe existing configuration blocks the whole transaction before Hopper installation or any file write. Declining or pressing Ctrl-C makes no changes. Agent configuration writes preserve unrelated entries, create backups, use atomic replacement, and verify their result. After setup, REA reports which agents, analysis tools, and workflow files passed its final checks. Restart any agent named in the completion message, then begin your investigation. Failed steps and diagnostics remain in terminal history. Select exact clients in scripts with repeatable `--client` flags. Each explicit client skips interactive selection. Use `--all-detected` only when you intend to configure every detected supported client. `--skill=false` omits the workflow, and `--dry-run` returns a read-only plan with status `planned` and exit code 0: ```bash rea setup --client codex --client cursor --skill=false --dry-run ``` Prompt UI and progress are written to stderr so stdout remains available for structured results and pipelines. `NO_COLOR=1` disables color. Use `--accessible` for sequential, vertically rendered yes/no prompts. Implicit interactive setup requires stdin, stdout, and stderr to all be terminals; when any stream is redirected, setup stays non-interactive. Declining or cancelling returns status `cancelled` with exit code 0. For automation, `rea setup --json` reports the plan and a compact `.doctor` readiness projection without applying it. Use `rea doctor --json` for full health diagnostics and canonical tool catalog details. Pair `--yes` with explicit scope such as `--client codex`, or use `--all-detected` when the broad scope is intended. Without a scope flag, `--yes` is limited to existing REA-owned registrations; it does not select all detected clients. An unapproved actual apply reports `needs_confirmation` and exits 1. Installing missing Hopper non-interactively additionally requires `--install-hopper`: ```bash rea setup --yes --all-detected --install-hopper --json ``` Setup pins package-runner MCP registrations to the exact installed REA version, installs the matching skill and on-demand references in the same plan, and adds `startup_timeout_sec = 30` for Codex. `rea update` installs the exact resolved release into the npm prefix that owns the running package, then checks the new executable's version before reporting success. It does not reopen onboarding. Release lookup and installation both use npm's configured registry. Its maintenance plan selects only existing REA registrations and an already installed REA skill. Run the returned scoped setup command to review and approve those changes, then restart affected agents. The plan is returned in terminal, non-TTY, and JSON modes without applying configuration changes. ## Hopper Hopper is separate commercial software with its own license. Its free demo has vendor-defined limits, and a paid license is optional. REA reuses any detected installation and preserves Hopper during uninstall. On macOS, approved setup downloads the official DMG, checks its published size and digest, validates the application bundle, and atomically installs it to `~/Applications/Hopper Disassembler.app`. REA then opens Hopper so the operator can choose its demo mode or activate an existing license. Homebrew and administrator access are not used. The Hopper launcher action used by REA creates a document from an executable; its supported command-line interface does not attach to an already-open document. While another live REA session owns the same target and loader profile, a second session reports the owning run ID instead of opening a duplicate document. Closing the owning REA session releases this guard; Hopper keeps its document open. A later REA session can therefore open another document for the same target. REA does not currently identify, focus, or reuse that existing GUI document, and the supported launcher exposes no attach or reuse action for it. On supported Linux distributions, approved setup verifies Hopper's official `.deb`, `.rpm`, or Arch package before invoking the native package manager. REA runs the supported demo build on a private Xvfb display and selects Hopper's offered demo mode for each analysis session; it does not require the user's desktop display. Unattended package-manager access requires `--yes --install-hopper`. If the host exposes `/tmp/.X11-unix` as an immutable mount, REA first verifies the conflict and then uses an unprivileged user and mount namespace with a private mode-1777 tmpfs over that directory only. The host mount and the rest of `/tmp` remain unchanged; this fallback never invokes `sudo`. `rea doctor --provider hopper --json` reports the selected strategy and both host and effective mount facts. ### Hopper in CI REA's unattended Linux path is validated against Hopper's offered demo mode. A paid license is not required for that path, and REA does not read, install, or automate license credentials. Licensed Hopper installations remain supported, but license activation is an operator-owned prerequisite rather than part of REA setup. macOS requires Hopper's first-run UI to be completed in the same user session that will run REA: choose the demo mode or activate an existing license before starting an unattended job. Ephemeral macOS runners therefore need a pre-provisioned user session or a deliberate interactive bootstrap step. When Hopper cannot start in CI, run `rea doctor --provider hopper --json` in the failing runner. Structured failures distinguish private-display dependencies, an unsupported demo dialog or build, process-ownership conflicts, and an early lifecycle exit. Apply the reported remediation rather than exposing the runner's desktop, copying license secrets into logs, or killing unrelated Hopper processes. ## Ghidra REA connects to an existing Ghidra installation on Linux x64 or macOS x64/arm64. It requires Ghidra 12.1.4 and a 64-bit full JDK 21. On macOS, the installation must include the native decompiler for the host architecture; REA does not build it or change Gatekeeper quarantine settings. The adapter exposes 22 read-only operations: ten inventory/name/search operations and twelve function-analysis operations. These cover metadata, decompilation, assembly, resolved calls, typed references, xrefs, function dossiers, instructions, and recovered data types. GUI controls and annotation changes require Hopper. Windows Ghidra operations are currently unavailable. The adapter reports `unsupported_host` until verified Job Object process ownership, private runtime DACLs, and reparse-safe path admission are implemented. The [Windows Ghidra P0 guide](windows-ghidra-p0.md) describes the intended boundary and remaining controls. Extract Ghidra and install the JDK outside REA, then export absolute paths: ```bash export GHIDRA_INSTALL_DIR=/absolute/path/to/ghidra_12.1.4_PUBLIC export JAVA_HOME=/absolute/path/to/jdk-21 # optional if java/javac are on PATH rea doctor --json rea setup ``` For Windows diagnostics, use the same installation paths in PowerShell. These settings do not enable the blocked analysis operations: ```powershell $env:GHIDRA_INSTALL_DIR = "C:\tools\ghidra_12.1.4_PUBLIC" $env:JAVA_HOME = "C:\Program Files\Java\jdk-21" rea doctor --json rea providers --json ``` `rea setup` can configure supported Windows agents and install the bundled REA skill after approval. Direct registrations use Node to launch REA's entry script; package-runner registrations use the pinned `npx` command. Hopper installation remains unavailable on Windows. Setup never installs Ghidra, Java, or Python, and agent registration does not enable blocked Ghidra operations. See [Windows Ghidra P0](windows-ghidra-p0.md) for provider diagnostics. Doctor validates the platform, architecture, application version, `support/analyzeHeadless` or `support/analyzeHeadless.bat`, Java version/bitness, and the presence of `javac`/`javac.exe`. When Java is found through `PATH`, setup records its observed JDK home so GUI MCP clients do not depend on an incidental shell path. Setup shows every exact environment entry in its plan, writes only after approval, and never downloads, installs, upgrades, or modifies Ghidra or Java. Each verified session uses an ephemeral temporary project and isolated home/cache/config/temp paths. REA passes `-readOnly`, `-deleteProject`, uses Ghidra's default analysis and resource settings, and loads its packaged Java bridge via `-scriptPath`; it never opens an existing user project. Linux and macOS use a current-user-only local bridge socket and descriptor. The experimental Windows transport uses authenticated IPv4 loopback, but missing native ownership and path controls keep Windows operations unavailable. Operations begin only after default auto-analysis completes. The provider startup deadline fails the open rather than exposing partial analysis. One session contains exactly one imported Program; use `provider_id: "ghidra"`, `--provider ghidra`, or `REA_ANALYSIS_PROVIDER=ghidra` when both Hopper and Ghidra support the target. One persistent decompiler is owned by the Program, and a serial queue keeps Ghidra API calls on the owning Program thread without a fixed queue length. Operations run until a result, caller cancellation, or provider shutdown; there is no fixed per-operation or response-size ceiling. Unresolved computed calls remain unknown, reference-kind provenance is preserved, and provider-specific pseudocode is never treated as original source or Hopper-equivalent text. Run `GHIDRA_INSTALL_DIR=... npm run verify:ghidra` from a source checkout to compile and analyze debug and stripped host-native fixtures (ELF on Linux x64 or Mach-O on macOS), plus a native DWARF 4 type-layout object. This lane needs a host C compiler in addition to Ghidra and its JDK. Run `GHIDRA_INSTALL_DIR=... npm run verify:ghidra:cross-format` to add AArch64 ELF, x86-64 PE, and x86-64 Mach-O fixture coverage. This separate lane needs `clang`, LLD, and `lld-link` on `PATH`; `REA_CLANG` and `REA_LLD_LINK` select alternate command paths. Missing cross-target tooling does not block the host-native Ghidra acceptance lane. On a controlled Windows x64 runner, use `npm run verify:ghidra:windows`. The verifier generates a deterministic native PE fixture from source bytes and requires the Windows native authority before opening the provider. This lane remains blocked until those controls are implemented; its intended checks include operation coverage, digest identity, and complete runtime cleanup. ## Diagnose, update, and remove `rea doctor --json` is strictly read-only. `rea update` updates only the npm installation that owns the running CLI. Source checkouts and package-runner copies must be updated through the mechanism that owns them; a fresh package-runner invocation can use `npx rea-agents@latest`. `rea uninstall` removes only REA-owned agent registrations and skill files; `--purge-data` additionally removes REA cache and state paths. ## MCP Registry REA is published in the official MCP Registry as `io.github.morluto/rea`. Registry clients can discover the server and install the existing public `rea-agents` npm package; the Registry entry does not introduce a second distribution artifact. For a client that supports Registry discovery, search for `io.github.morluto/rea` and select the npm package. The published metadata launches the existing stdio server through `npx` with the `mcp` command. For a client that requires manual configuration, use: ```json { "mcpServers": { "rea": { "command": "npx", "args": ["-y", "rea-agents@latest", "mcp"] } } } ``` Use an exact `rea-agents@VERSION` in the arguments when a reproducible client configuration is required. `rea setup` writes the same package-runner shape and pins it to the exact version that performed setup.