Show HN: CLI and MCP for model fusion via harnesses

Parley, a new CLI and MCP server, enables local multi-model deliberation by fusing answers from multiple AI coding agents like Claude, Codex, and Gemini into a single response, providing consensus or flagging disagreements without sending code to external APIs.

Your coding agents are smarter together. A CLI and an MCP server that convene a panel of the agents you already run — Claude, Codex, Gemini, and more — and fuse their answers into one. A single agent is a single model's judgment — one set of blind spots. Parley sends the same problem to a panel of agent CLIs, then fuses their replies: where they agree you get high-confidence consensus, where they disagree you get a flag worth your attention, and what none caught the panel surfaces. This is the multi-model deliberation behind Sakana's AB-MCTS and — both report combined models beating any single one — but running over the CLIs already on your machine, with OpenRouter's Fusion https://openrouter.ai/blog/announcements/fusion-beats-frontier/ their auth and your context. No API keys. No new vendor. Your code never leaves. Parley is first-class both ways — a CLI you drive, and an MCP server your agent drives. Same engine, same capabilities, whichever side you call it from: | Capability | CLI — you run it | MCP — your agent calls it | |---|---|---| Fuse a panel into one answer | par fuse "design a rate limiter" | fuse tool | Ask another agent, with context | par ask -h g -p "…" --context-from cl | ask agent tool | Resume any agent's session here | par resume | list sessions · get last session · resume command | Converse — two agents, multi-turn | par converse --a cl --b g -p "…" | compose via ask agent | Route a prompt to any agent | par -p "…" -h <agent | — | Convert one config to every agent | par convert | — | Drive it yourself… par fuse "design a rate limiter for this service" panel + judge → one fused answer …or wire it into your agent once, and let Claude convene the panel mid-task: par mcp connect -h cl registers the MCP server into Claude then just say: "fuse this across codex and gemini" → Claude calls the fuse tool itself Parley is a small, dependency-free Rust CLI binary: par . It never calls a model API itself — it drives the agent CLIs you already have, so your auth, models, and permissions stay with them. The MCP server exposes the very same operations as tools, so nothing is locked to one surface. A single agent is a single point of view. Every coding agent ships one model's training, one model's failure modes, one model's blind spots. On the calls that matter — an architecture decision, a security review, a tricky migration — there's no second opinion, no disagreement to flag risk, no way to combine the model that reasons best with the model that writes the best code. Research labs already proved the fix. Sakana's AB-MCTS lets frontier models cooperate at inference time and reports problems no single model could solve becoming solvable. OpenRouter's Fusion runs a panel plus a judge and reports a fused pair beating every individual model. The catch with both: API-side, single-vendor, and your code leaves your machine. Parley does it locally — and fixes the other half of the problem, that the agents are silos. Each CLI has its own headless interface claude -p , codex exec , gemini --prompt , goose run -t , opencode run , aider --message , its own config format, and its own on-disk session store — none can see each other. So: Agents can't combine. Two models with different strengths have no way to review each other's work, debate, or vote on an answer. Scripts are brittle. Switching agents means rewriting commands, model flags, provider syntax, and env vars. Config is duplicated. The same instructions, commands, and MCP servers get hand-maintained once per agent. Work gets stranded. A conversation lives inside whichever agent you started in; you can't pick it up elsewhere. Parley is the interoperability layer that removes all four — and turns it into collective intelligence: Fuse — par fuse "..." sends your prompt to a panel of agents in parallel, then a judge Claude by default synthesizes one answer from their consensus, contradictions, and blind spots. Same thing is an MCP tool , so an agent can convene its own panel mid-task — escalation when a question is worth more than one model. One interface — route any prompt to any agent by changing a single flag par -p , -h <agent . The adapter owns the translation. One config — author your .claude/ pack once, par convert generates each agent's native config from it. Portable sessions — par resume lists and resumes any agent's past sessions for this folder, regardless of which agent created them. Agents that collaborate — par ask lets one agent query another seeded with a shared session's context , and par converse puts two agents in a multi-turn conversation. Expose it over MCP with par mcp so an agent can do this itself — "ask Gemini to review this, with my Claude context." The result: your automation describes intent , not which agent is wired up today — and your agents stop being islands and start being a team. New to fusion?The Fusion Playbook is the how-to for ~10× better results: when to fuse, how to pick a diverse panel, and the debate / wider-deeper / second-opinion patterns. One command: curl --proto '=https' --tlsv1.2 -sSf https://raw.githubusercontent.com/KerryRitter/parley/main/install.sh | sh This installs par into ~/.local/bin plus an agent-router alias . Make sure that directory is on your PATH : export PATH="$HOME/.local/bin:$PATH" par --version verify par routes to agent CLIs — it does not install them for you automatically. Install the agents you want with , or bring your own. par install From source needs Rust https://sh.rustup.rs : git clone https://github.com/KerryRitter/parley.git cd parley scripts/setup.sh --install validates, then cargo install --path . --force This creates ~/.local/bin/par and ~/.local/bin/agent-router - par . Ensure both ~/.cargo/bin and ~/.local/bin are on your PATH . Direct from GitHub: cargo install --git https://github.com/KerryRitter/parley.git --branch main --force Install-script options append after sh -s -- : ... | sh -s -- --install-dir /usr/local/bin custom location ... | sh -s -- --from-source force a source build ... | sh -s -- --from-source --git-protocol ssh ... | sh -s -- --no-agent-router skip the agent-router alias The script installs a prebuilt release binary for your platform when available, and falls back to a source build otherwise. Release-binary and Homebrew distribution are planned; see Release Plan release-plan . | Command | Capability | |---|---| par -p "..." | par fuse "..." par default <agent par install <agent par shims install claudey / codexy one-shot shortcuts par convert .claude/ config to every other agent par resume par ask par converse par mcp fuse a panel, ask each other, and resume sessions par launch the default agent interactively par -p "summarize this repository" one-shot prompt par -h co -m gpt-5.4 -p "add tests" choose an agent + model git diff | par -p "review this patch" pipe context in par -p "review src" --dry-run print the routed command instead of running it Choosing the agent — -h / --harness takes a full name or a short code: | Code | Agent | Code | Agent | Code | Agent | |---|---|---|---|---|---| cl | claude | g | gemini | q | qwen | co | codex | go | goose | a / ai | aider | cu | cursor | oc | opencode | aq | amazon-q | cp | copilot | k | kimi | ag | antigravity | par -h cl "review this" par -h co -m gpt-5.4 "fix tests" par -h k -p "drain the queue" Bare -h no value prints help; -h <name selects an agent. | Flag | Purpose | |---|---| -p , --prompt , --print | Prompt text --print is accepted for Claude compatibility . | -h , --harness <name | Target agent. Defaults to claude . Accepts short codes. | --provider <name | Provider namespace, when the agent uses provider-qualified models or env config. | -m , --model <name | Model name. | --agent <name | Agent/persona/profile, where supported. | --output-format <fmt | Output mode e.g. json , where supported. | --input-format <fmt | Claude-compatible input format. | --permission-mode <mode | Permission/sandbox mode, where supported. | --max-turns <n | Max agent turns, where supported. | --cwd <path | Working directory for the child process. | --yolo / --no-yolo | Add / skip the agent's permission-bypass flag. On by default. | --dry-run | Print the routed invocation as JSON; run nothing. | --version , -v | Print version. | --help | Print help. | -- | Pass everything after it straight to the agent CLI. | Pass agent-specific flags after -- : par -h cl -p "review this" -- --verbose par -h aider -p "fix lint" -- --yes --no-auto-commits How prompt input is resolved: - No prompt and no stdin → launch the agent's interactive entrypoint. - stdin piped and -p given → stdin is placed before the prompt, blank line between. - stdin piped, no -p → stdin becomes the prompt. Every run adds the agent's permission-bypass flag e.g. --dangerously-skip-permissions for Claude so automation runs hands-off. Opt out per run with --no-yolo , or persistently with PARLEY YOLO=false . Agents with no known bypass flag e.g. Amazon Q simply run without one. Opt out when running untrusted prompts or in sensitive directories. So you don't repeat -h every time: par default codex set default agent par default claude --yolo set agent + persist yolo par default --no-yolo keep agent, disable yolo par default show current defaults par default --path print the config file path par current alias for showing defaults par list list supported agent names The default lives in ~/.config/par/default or $XDG CONFIG HOME/par/default ; override with PAR DEFAULT FILE . export PARLEY HARNESS=codex export PARLEY PROVIDER=openai export PARLEY MODEL=gpt-5.4 export PARLEY YOLO=true legacy AGENT ROUTER names are still honored as a fallback Generate y one-shot shortcuts for yolo-capable agents: par shims install writes claudey, codexy, ... to ~/.local/bin claudey -p "work in this sandbox" codexy "work in this sandbox" Override the location with par shims install --dir <dir or PAR SHIM DIR . par shims list prints the generated names and commands. par fuse is the collective-intelligence command. It sends your prompt to a panel of agents in parallel , then hands every reply to a judge agent — Claude by default — that synthesizes a single answer: where the panel agreed high-confidence , where it disagreed and who's right, and what it missed. Same idea as OpenRouter's Fusion and Sakana's AB-MCTS, over the CLIs you already run. It's available both as this command and as an MCP tool mcp--fuse-ask-and-resume-from-inside-your-agent so an agent can convene its own panel mid-task. par fuse -p "design a rate limiter for a multi-tenant API" default panel: claude, codex, gemini par fuse "is this migration safe to run on a live DB?" --panel cl,co,k par fuse "..." --judge co --judge-model gpt-5.4 choose the judge and its model par fuse "..." --context-from cl seed every panelist with your latest claude session here par fuse "..." --panel cl,co,g --dry-run print every routed command panel + judge , run nothing | Flag | Purpose | |---|---| --panel <codes | Comma-separated panel agents short codes allowed . Defaults to claude,codex,gemini . Needs ≥2; duplicates are allowed self-pairing is a valid technique . | --judge <agent | Agent that synthesizes the panel. Defaults to claude. | --judge-model <m | Model for the judge. | --context-from <h :s | Prepend a prior session's transcript to every panelist, so the panel deliberates with your context sources: claude , codex , opencode . | --max-context , --cwd , --no-yolo , --dry-run | As in par ask | Panelists run concurrently , so wall-clock ≈ the slowest agent + the judge, and cost ≈ N+1 agent runs. A panelist whose CLI isn't installed is skipped with a note; fusion needs at least two to succeed. Alias: par panel . Fuse selectively — it's escalation, not autopilot. Reach for it on the calls where being wrong is expensive design, security, migrations , and use a diverse panel different vendors, not three of the same model . The Fusion Playbook /KerryRitter/parley/blob/main/docs/fusion-playbook.md covers when to fuse, how to pick the panel, and the debate / wider-deeper patterns that stack on top. par can install the downstream agents it routes to: par install list show installer coverage par install claude install one agent par install all install every supported agent par install --dry-run all print the exact upstream commands, run nothing The registry is transparent — --dry-run prints the real upstream install command. Agents without a stable one-liner e.g. Amazon Q print the official install page and a verify command instead of guessing. | Agent | Installer | |---|---| claude | curl -fsSL https://claude.ai/install.sh | bash | codex | npm install -g @openai/codex | cursor | curl https://cursor.com/install -fsS | bash | gemini | npm install -g @google/gemini-cli | goose | curl -fsSL https://github.com/block/goose/releases/download/stable/download cli.sh | bash | opencode | curl -fsSL https://opencode.ai/install | bash | qwen | curl -fsSL https://qwen-code-assets.oss-cn-hangzhou.aliyuncs.com/installation/install-qwen.sh | bash | aider | curl -LsSf https://aider.chat/install.sh | sh | amazon-q | Manual official installer page; verify with q --version | copilot | curl -fsSL https://gh.io/copilot-install | bash | kimi | curl -LsSf https://code.kimi.com/install.sh | bash | antigravity | curl -fsSL https://antigravity.google/cli/install.sh | bash | par does not manage agent versions; each downstream CLI owns its own upgrade flow. par convert ports a Claude command/skill pack to other agents. Your .claude/ directory commands, skills, agents/ , references , CLAUDE.md , and .mcp.json stay the single source of truth ; convert generates each agent's native config from them. php par convert claude - all targets par convert --to kimi claude - one target par convert --from claude --to codex par convert --dry-run show what would be written par convert --cwd path/to/project Source: claude . Targets: gemini , codex , antigravity , opencode , cursor , kimi . What it does: Parses frontmatter — real descriptions, per-command model , argument placeholders; strips the block from bodies. Reads commands, skills, personas .claude/agents/ , references, and .mcp.json . Emits native artifacts per target — e.g. .kimi/skills/<name /SKILL.md + .kimi/mcp.json , .codex/config.toml + .agents/skills/ , .gemini/commands/ .toml + GEMINI.md , .cursor/rules/ , .opencode/config.json , plus AGENTS.md . MCP servers in .mcp.json are translated into each agent's format. Resolves cross-references — every /command , skill skill , persona path, and reference path is checked against the pack. The run prints a resolution report and exits non-zero if any reference dead-ends , so a typo fails the convert instead of shipping a broken pack. Generated skills carry a par-convert:generated marker, so re-running replaces only its own output and never a hand-authored file. Commit .claude/ ; git-ignore the generated output. A typical npm run sync:instructions is just par convert --from claude --to all . par resume browses and resumes sessions from any agent, scoped to the current directory — the same scoping every agent's own --resume uses. It reads the transcripts each agent already writes to disk; there are no extra files to maintain. par resume list this folder's sessions any agent , pick one par resume -h cl resume a claude session here picker if several par resume -h co --latest resume the newest codex session, no prompt par resume --list print the listing, resume nothing par resume --list --json machine-readable listing par resume -h cl <id --print print the resume command for a session id par resume --cwd path/to/proj scope to another directory A selector is either a list index par resume 2 or a raw session id par resume -h cl <id . Add --yolo to append the agent's permission-bypass flag off by default here, since resume drops into an interactive session . Two tiers of support: Native listing — claude , codex , opencode . Read straight from disk ~/.claude/projects/<slug / , ~/.codex/sessions/ , ~/.local/share/opencode/storage/session/ , matched on exact cwd, with title and recency. These show up in the cross-agent listing. Delegate resume — cursor , gemini . Their stores are hash-scoped in a way par doesn't reproduce, but the binaries self-scope to the cwd. Listing is skipped marked ~ ; resume runs the agent's own cwd-scoped resume cursor-agent resume , gemini --resume latest . par resume -h cu / par resume -h g work directly. par ask runs another agent headless and returns its reply as text. Because par already routes a prompt to any agent, "Claude asks Gemini" is just routing the prompt to Gemini and capturing its output. With --context-from , par first reads a prior session's transcript and prepends it — so the answer is informed by that history. This is the cross-agent context bridge . par ask -h g -p "critique this approach in 3 bullets" ask gemini, print its reply par ask -h g -p "what did we decide?" --context-from cl seed with your latest claude session here par ask -h cl -p "continue this" --context-from co:<id use a specific source session id par ask -h g -p "..." --max-context 8000 cap injected context default 12000 chars par ask -h g -p "..." --dry-run show the routed command + final prompt, run nothing --context-from takes harness :session ; omit the session or use latest for the newest in the directory. Context sources: claude , codex , opencode full transcripts . cursor / gemini can't export transcripts, so they can't be context sources — they can still be asked. Notes: each call is one-shot the target keeps no memory between asks ; yolo is on by default so the headless agent can't block on a permission prompt; long transcripts are truncated to the most recent turns within the budget. par converse puts two agents in one conversation: A speaks, B replies, A replies, and so on. Each agent is stateless and headless, so par itself holds the running dialogue and feeds it back every turn — par ask 's context bridge, accumulated across the loop. Output streams turn by turn so you can watch them work. par converse --a cl --b g -p "Design a rate limiter; A proposes, B critiques." par converse --a cl --b g -p "Agree on a name." --turns 8 --until AGREED par converse --a cl --b g -p "Continue this." --context-from co seed turn 1 with a codex session par converse --a cl --b g -p "..." --a-model <m --b-model <m --dry-run --a / --b — the two agents short codes allowed . --a-model / --b-model set per-agent models. --turns N — total turns, alternating, starting with A default 6; capped at 50 . --until <phrase — stop early when a reply contains the phrase agents are told to emit it when done . --context-from harness :session — seed the first turn with a prior session's transcript. --max-context , --cwd , --no-yolo , --dry-run as in par ask . Aliases: par debate , par relay . Each turn spawns a full agent process, so cost and latency scale with --turns . The loop is two-party; --until is the way to end before the turn budget. par mcp runs a small MCP https://modelcontextprotocol.io server over stdio newline-delimited JSON-RPC 2.0 , so any MCP-capable agent can convene a panel and fuse it , ask other agents questions, and resume sessions — all from inside the agent you're already in. This is how you say "fuse this across Codex and Gemini" , "ask Gemini to review this with my Claude context" , or "pick up my last conversation from Claude" without leaving your agent. Tools: — the collective-intelligence tool. Sends fuse {prompt, panel?, judge?, judge model?, cwd?, context from?: {harness, session?}} prompt to every agent in panel default claude,codex,gemini in parallel , then a judge agent judge , default claude synthesizes one answer — consensus as high-confidence, contradictions resolved, gaps filled, blind spots flagged — and returns it as text. context from seeds every panelist with a prior session. Needs ≥2 panelists; ones whose CLI isn't installed are skipped with a note. Same engine as the par fuse command. ask agent {harness, prompt, model?, provider?, cwd?, context from?: {harness, session?}} — run another agent headless and return its reply, optionally seeded with a session transcript. The agent-to-agent / context-bridge primitive. list sessions {cwd?, harness?} — resumable sessions for a directory, newest first. get last session {cwd?, harness?} — the most recent session plus a ready-to-run resume command. resume command {harness, id, cwd?, yolo?} — build the native resume command for a session id text; never spawns an interactive agent . Why fuse is also a tool, not just a command: like OpenRouter's Fusion, fusion is escalation, not autopilot — exposing it as a tool lets the model decide a question is worth more than one opinion and convene the panel itself, mid-task, without you running anything. The par fuse command does the same thing from the terminal. Use a diverse panel different vendors, not three of the same model . The Fusion Playbook /KerryRitter/parley/blob/main/docs/fusion-playbook.md covers when to fuse and how to pick the panel; the debate par converse and wider→deeper patterns stack on top. "fuse this across codex and gemini: is this migration safe on a live DB?"→ the agent calls fuse , Parley runs Claude+Codex+Gemini in parallel, and the agent writes one answer grounded in all three. Register it into an agent — par mcp connect runs whatever that agent needs: php par mcp connect -h cl claude - runs claude mcp add -s user par -- <par mcp par mcp connect -h co codex - runs codex mcp add par -- <par mcp par mcp connect -h g gemini - runs gemini mcp add par <par mcp par mcp connect -h oc opencode - opens its own interactive opencode mcp add par mcp connect -h cu cursor - merges ~/.cursor/mcp.json no add command exists par mcp connect -h cl --dry-run show the exact command / file change, do nothing connect registers the absolute path of the running par , so it works regardless of the caller's PATH . Agents with a native mcp add are invoked directly some, like opencode, prompt in their own TUI ; cursor has no add subcommand, so its config file is merged in place, preserving existing servers. Then, from any registered agent: "use par to pick up my last claude session here" → the agent calls get last session and runs the returned claude --resume <id . | Agent | Aliases | Routed command | |---|---|---| claude | cl | claude -p "<prompt " | codex | co , openai | codex exec "<prompt " | cursor | cu , cursor-agent | cursor-agent -p "<prompt " | gemini | g , google , google-gemini | gemini --prompt "<prompt " | goose | go | goose run -t "<prompt " | opencode | oc , open-code | opencode run "<prompt " | qwen | q | qwen -p "<prompt " | aider | a , ai | aider --message "<prompt " | amazon-q | aq , amazonq , aws-q , amazon | q chat "<prompt " | copilot | cp , github-copilot | copilot -p "<prompt " | kimi | k , moonshot , kimi-code | kimi -p "<prompt " | antigravity | ag , agy , google-antigravity | agy "<prompt " | Per-agent flag mappings Claude — claude -p . Supports --model , --output-format , --input-format , --permission-mode , --max-turns . Yolo → --dangerously-skip-permissions . Codex — codex exec . --output-format json|stream-json → --json . Provider is preserved in PARLEY PROVIDER Codex receives the plain model name . Yolo → --dangerously-bypass-approvals-and-sandbox for routed runs; the codexy shim uses codex --yolo . Cursor — cursor-agent -p . Plain --model ; --output-format when accepted. Yolo → --force required for print-mode file writes . Gemini — gemini --prompt . Plain --model ; --output-format when accepted. Yolo → --yolo . Goose — goose run -t . --provider → GOOSE PROVIDER , --model → GOOSE MODEL , --permission-mode → GOOSE MODE , --max-turns → GOOSE MAX TURNS , --agent → --with-builtin . Yolo sets GOOSE MODE=auto unless --permission-mode is given. OpenCode — opencode run . --provider anthropic --model claude-sonnet-4-6 → --model anthropic/claude-sonnet-4-6 . --output-format json|stream-json → --format json . --agent → --agent . Yolo → --dangerously-skip-permissions . Qwen — qwen -p . Plain --model ; --output-format when accepted. Yolo → --yolo . Aider — aider --message . Provider+model joined for --model e.g. anthropic/claude-sonnet-4-6 . Use -- for Aider flags like --yes . Yolo → --yes-always . Amazon Q — q chat . --agent → --agent . Model selection owned by Amazon Q config. Copilot — provisional. copilot -p . Yolo → --yolo . Validate against the installed CLI before relying on it. Kimi — kimi -p . Plain --model , --output-format . Yolo → --yolo . Auto-loads project MCP: when ./.kimi/mcp.json exists relative to --cwd or the process cwd , the adapter adds --mcp-config-file <cwd /.kimi/mcp.json , so the project config generated by par convert loads automatically. Antigravity — experimental. Uses the agy command. Docs currently describe the interactive AGY CLI rather than a headless mode; the adapter passes the prompt and leaves version-specific flags to -- . Yolo → --dangerously-skip-permissions . scripts/setup.sh full local validation fmt, test, clippy, release build, agent check scripts/setup.sh --strict-harnesses also require at least one agent CLI installed scripts/setup.sh --install validate, then install the binary Direct commands: cargo fmt cargo test cargo clippy --all-targets -- -D warnings cargo build --release cargo run -- -h oc --provider anthropic --model claude-sonnet-4-6 -p "review" --dry-run Expected --dry-run shape: { "command": "opencode", "args": "run", "--model", "anthropic/claude-sonnet-4-6", "review" , "env": {} } src/ main.rs entrypoint, stdin handling, dry-run, dispatch cli.rs command-line parser model.rs provider/model resolution process.rs child process execution inherit-stdio run + captured run json.rs zero-dep JSON parser/serializer used by convert, session, ask, mcp ask.rs agent-to-agent calls headless run + transcript context injection converse.rs multi-turn two-agent conversation loop fuse.rs panel fusion engine — parallel panel + judge par fuse and the mcp fuse tool mcp.rs stdio MCP server resume tools + ask agent + fuse + mcp connect harness/ per-agent adapters claude, codex, cursor, gemini, goose, opencode, qwen, aider, amazon q, copilot, kimi, antigravity mod.rs Harness trait, Request, HarnessFactory, normalize harness invocation.rs command/args/env representation convert/ .claude/ reader + per-target writers + cross-reference resolver session/ cross-agent session discovery, resume, and transcript export mod.rs SessionStore trait, SessionRef, Turn, listing + resume + context claude.rs codex.rs opencode.rs native parsers cwd-scoped listing + transcripts cursor.rs gemini.rs delegate adapters resume via native CLI installer.rs agent installer registry Design constraints: no sh -c adapters build argv directly ; no hidden API calls only starts local CLIs ; no login handling authenticate each agent separately ; agent-specific behavior stays in its module; provider/model transforms stay centralized in model.rs ; --dry-run output stays stable enough for tests. - Create src/harness/<name .rs and implement Harness for a small adapter struct. - Register it in HarnessFactory::default . - Add aliases in normalize harness if useful. - Add dry-run tests command, args, provider/model, env, passthrough . - Document it in this README. use super::{add passthrough, plain model, Harness, Invocation, Request}; pub crate fn new - Box<dyn Harness { Box::new ExampleHarness } struct ExampleHarness; impl Harness for ExampleHarness { fn build &self, request: &Request - Result<Invocation, String { let mut args = vec "run".to string , request.prompt.clone ; if let Some model = plain model request { args.extend "--model".to string , model ; } Ok Invocation::new "example", add passthrough args, request } } Working infrastructure for local automation. Done: dependency-free Rust CLI · shared claude -p -style prompt surface · isolated per-agent adapters · agent installers · provider/model resolution · dry-run routing · cross-agent session resume · agent-to-agent calls with context bridging · multi-turn two-agent conversations · panel fusion par fuse + mcp fuse tool · stdio MCP server · validating setup script. Not yet: GitHub Actions release builds · Homebrew formula · end-to-end smoke tests against every vendor CLI · a stable semver contract per agent mapping. scripts/setup.sh .- Smoke-test locally available CLIs with --dry-run . - CI: cargo fmt --check , cargo test , cargo clippy --all-targets -- -D warnings , and release binaries for Linux/macOS/Windows par-<target .tar.gz / .zip . - Add archive checksums, publish a GitHub release. - Add a Homebrew tap once artifact names are stable. par does not inspect or redact prompt content. Anything passed via stdin or -p is forwarded to the selected agent, which may send it to its configured provider. Yolo permission bypass is on by default — each run adds the agent's bypass flag unless you pass --no-yolo or set PARLEY YOLO=false . This favors hands-off automation over sandboxing; opt out for untrusted prompts or sensitive directories. Use --dry-run to validate automation that may include secrets before running it. Written against public docs checked May 19, 2026 : Claude https://code.claude.com/docs/en/cli-reference , Codex https://www.mintlify.com/openai/codex/advanced/exec-mode , Cursor https://docs.cursor.com/en/cli/using , Gemini https://google-gemini.github.io/gemini-cli/docs/cli/ , OpenCode https://dev.opencode.ai/docs/cli/ , Qwen https://qwenlm.github.io/qwen-code-docs/en/cli/index , Aider https://aider.chat/docs/scripting.html , Amazon Q https://docs.aws.amazon.com/amazonq/latest/qdeveloper-ug/command-line-reference.html , Goose https://block.github.io/goose/docs/tutorials/headless-goose/ , Antigravity https://antigravity.google/docs/cli-using . Installer commands live in src/installer.rs . Agent CLIs change fast — re-check these surfaces before a public release.