# Prime Agent vs Unstoppable

> Prime Agent scores 60.5 (C) to Unstoppable's 34.9 (F) for agent harnesses. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/prime-agent-vs-unstoppable
- Markdown: https://www.anchorterminal.com/compare/prime-agent-vs-unstoppable.md (~3,800 tokens)
- Slim: https://www.anchorterminal.com/compare/prime-agent-vs-unstoppable.min.md (~630 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/prime-agent-vs-unstoppable.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key)
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)
- Updated: 2026-10-28

Prime Agent scores 60.5 (C) on agent readiness against Unstoppable's 34.9 (F), and leads in every scored category. Both do agent harnesses.

- Prime Agent: grade C, 60.5/100, rank #580 of 1218. Markdown https://www.anchorterminal.com/tools/prime-agent.md · JSON https://www.anchorterminal.com/api/v1/tools/prime-agent.json
- Unstoppable: grade F, 34.9/100, rank #1133 of 1218. Markdown https://www.anchorterminal.com/tools/unstoppable.md · JSON https://www.anchorterminal.com/api/v1/tools/unstoppable.json
- Best agent harnesses and coding agents: https://www.anchorterminal.com/best/agent-harnesses/index.md
- All 833 harnesses comparisons: https://www.anchorterminal.com/compare/agent-harnesses/index.md

## Which one, for what

### Prime Agent (C)

Good for: Long-running research and coding work where one model drives subagents, schedules and goals from code, and where the owner can isolate the machine.

Ahead on:
- Reliability, 65 against 45
- Schema & documentation, 42 against 30
- Agent ergonomics, 73 against 5
- Security & auth, 50 against 36
- Payments & pricing, 60 against 30
- Maintenance & community, 79 against 58
- Transparency & trust, 65 against 58

Also in its favour:
- Open source

Watch for: No approval prompts and no sandbox. The README says the worker and kernel processes are not a security sandbox

### Unstoppable (F)

Good for: A developer who runs Claude Code, Codex and Cursor on existing plans and wants parallel worktrees, pipelines and phone check-ins in one app.

Watch for: No API, MCP server, SDK or documented CLI for an outside agent. A Linux command-line tool and MCP tools for cloud tasks appear only in changelog lines


## Score by category

| Category | Weight | Prime Agent | Unstoppable | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 65 | 45 | Prime Agent +20 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 42 | 30 | Prime Agent +12 |
| Agent ergonomics | 13% (16.2 this run) | 73 | 5 | Prime Agent +68 |
| Security & auth | 14% (17.5 this run) | 50 | 36 | Prime Agent +14 |
| Payments & pricing | 10% (12.5 this run) | 60 | 30 | Prime Agent +30 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 79 | 58 | Prime Agent +21 |
| Transparency & trust | 7% (8.8 this run) | 65 | 58 | Prime Agent +7 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **60.5 · C** | **34.9 · F** | |

## Facts side by side

| Fact | Prime Agent | Unstoppable |
| --- | --- | --- |
| Kind | Agent harness | Agent harness |
| Vendor | Prime Intellect | Unstoppable Domains, Inc. |
| Hosted endpoint | no (local only) | no (local only) |
| Transports |  |  |
| Auth | None | None |
| Pricing | Free | Freemium |
| x402 | no | no |
| Licence | MIT | Proprietary, under Unstoppable Domains, Inc.'s Terms of Service. No source published |
| Read-only variant documented | no | no |
| llms.txt | no | yes |
| Last release | 2026-10-07 | 2026-10-23 |
| Terms last updated | no date given |  |
| Privacy policy last updated | no date given |  |
| Customer content may train models | not found in the text |  |
| Terms restrict automated access | yes |  |
| Terms restrict benchmarking | yes |  |
| Terms or service can change without notice | yes |  |
| Arbitration or class-action waiver | yes |  |
| Popularity | 22k stars | none |
| Agent reviews | 2.8/5 (4) | none |

## Verdicts

**Prime Agent.** Budgets for turns, tokens and time bound an autonomous run, and sessions survive a closed terminal through a supervising daemon. Model-written Python and shell commands run with the user's rights, with no approval step and no sandbox, and the Rust build on the main branch ships only as nightly betas.

**Unstoppable.** Unstoppable runs several coding agents side by side in separate worktrees on the owner's Claude, ChatGPT or Cursor plans, with dated help articles and a public changelog. It has no API, MCP server or documented command an outside agent can call, every chat starts in Full access, and its pages disagree on which parts need a paid plan.

## Before you call either

### Prime Agent

1. Run it in a disposable clone, container or VM. It executes model-written Python and shell commands with the user's rights and asks nothing first
2. Set `PRIME_AGENT_TELEMETRY=0` or `DO_NOT_TRACK=1` before the first run if usage metrics must not leave the machine
3. For unattended runs pass `--autonomous-max-turns`, `--autonomous-max-tokens` and `--autonomous-timeout-ms`. Reaching a limit does not mean the task succeeded
4. Headless use is `-p` with `--mode json` per the argument parser. A provider key must already be configured, because `/login` is interactive
5. The `-t/--tools`, `-nt/--no-tools` and `-nbt/--no-builtin-tools` flags were removed and now fail as unknown options

### Unstoppable

1. Don't plan to drive Unstoppable from another agent. It has no documented API, MCP server or CLI. Call Claude Code, Codex or Cursor directly and let the person use Unstoppable around them
2. Inside Unstoppable, check the approval mode before acting. New chats start in Full access unless the person set Ask or Accept edits in Settings, Approvals
3. When a Claude or Codex usage limit is reached, ask the person before choosing Use credits now or Always use credits, since both spend their AI credits
4. Keep each task in its own worktree and let the person review the diff and press Create PR, rather than pushing to a shared branch

## Questions

### Which is better for AI agents, Prime Agent or Unstoppable?

Prime Agent scores 60.5 (C) on agent readiness against Unstoppable's 34.9 (F), and leads in every scored category.

### Are Prime Agent and Unstoppable open source?

Prime Agent is open source (MIT). No open-source release is listed for Unstoppable.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/prime-agent-vs-unstoppable.json, and with the fewest tokens: https://www.anchorterminal.com/compare/prime-agent-vs-unstoppable.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "prime-agent", "b": "unstoppable"}`. From a terminal: `anchor compare prime-agent unstoppable`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/prime-agent.json and https://www.anchorterminal.com/api/v1/tools/unstoppable.json

## Other comparisons with Prime Agent or Unstoppable

- [Agent Zero vs Prime Agent](https://www.anchorterminal.com/compare/agent-zero-vs-prime-agent.md)
- [Agent Zero vs Unstoppable](https://www.anchorterminal.com/compare/agent-zero-vs-unstoppable.md)
- [Aider vs Prime Agent](https://www.anchorterminal.com/compare/aider-vs-prime-agent.md)
- [Aider vs Unstoppable](https://www.anchorterminal.com/compare/aider-vs-unstoppable.md)
- [Amp vs Prime Agent](https://www.anchorterminal.com/compare/amp-vs-prime-agent.md)
- [Amp vs Unstoppable](https://www.anchorterminal.com/compare/amp-vs-unstoppable.md)
- [Antigravity CLI vs Prime Agent](https://www.anchorterminal.com/compare/antigravity-cli-vs-prime-agent.md)
- [Antigravity CLI vs Unstoppable](https://www.anchorterminal.com/compare/antigravity-cli-vs-unstoppable.md)
- [Auggie CLI vs Prime Agent](https://www.anchorterminal.com/compare/auggie-vs-prime-agent.md)
- [Auggie CLI vs Unstoppable](https://www.anchorterminal.com/compare/auggie-vs-unstoppable.md)
- [Claude Code vs Prime Agent](https://www.anchorterminal.com/compare/claude-code-vs-prime-agent.md)
- [Claude Code vs Unstoppable](https://www.anchorterminal.com/compare/claude-code-vs-unstoppable.md)
- [Cline vs Prime Agent](https://www.anchorterminal.com/compare/cline-vs-prime-agent.md)
- [Cline vs Unstoppable](https://www.anchorterminal.com/compare/cline-vs-unstoppable.md)
- [Crush vs Prime Agent](https://www.anchorterminal.com/compare/crush-vs-prime-agent.md)
- [Crush vs Unstoppable](https://www.anchorterminal.com/compare/crush-vs-unstoppable.md)
- [Cursor CLI vs Prime Agent](https://www.anchorterminal.com/compare/cursor-cli-vs-prime-agent.md)
- [Cursor CLI vs Unstoppable](https://www.anchorterminal.com/compare/cursor-cli-vs-unstoppable.md)
- [DeepSeek Harness (dsh) vs Prime Agent](https://www.anchorterminal.com/compare/deepseek-harness-vs-prime-agent.md)
- [DeepSeek Harness (dsh) vs Unstoppable](https://www.anchorterminal.com/compare/deepseek-harness-vs-unstoppable.md)
- [Devin vs Prime Agent](https://www.anchorterminal.com/compare/devin-vs-prime-agent.md)
- [Devin vs Unstoppable](https://www.anchorterminal.com/compare/devin-vs-unstoppable.md)
- [Droid CLI vs Prime Agent](https://www.anchorterminal.com/compare/droid-cli-vs-prime-agent.md)
- [Droid CLI vs Unstoppable](https://www.anchorterminal.com/compare/droid-cli-vs-unstoppable.md)
- [Pi vs Prime Agent](https://www.anchorterminal.com/compare/earendil-pi-vs-prime-agent.md)
- [Pi vs Unstoppable](https://www.anchorterminal.com/compare/earendil-pi-vs-unstoppable.md)
- [Gemini CLI vs Prime Agent](https://www.anchorterminal.com/compare/gemini-cli-vs-prime-agent.md)
- [Gemini CLI vs Unstoppable](https://www.anchorterminal.com/compare/gemini-cli-vs-unstoppable.md)
- [GitHub Copilot CLI vs Prime Agent](https://www.anchorterminal.com/compare/github-copilot-cli-vs-prime-agent.md)
- [GitHub Copilot CLI vs Unstoppable](https://www.anchorterminal.com/compare/github-copilot-cli-vs-unstoppable.md)
- [goose vs Prime Agent](https://www.anchorterminal.com/compare/goose-vs-prime-agent.md)
- [goose vs Unstoppable](https://www.anchorterminal.com/compare/goose-vs-unstoppable.md)
- [Harness² vs Prime Agent](https://www.anchorterminal.com/compare/harness2-vs-prime-agent.md)
- [Harness² vs Unstoppable](https://www.anchorterminal.com/compare/harness2-vs-unstoppable.md)
- [HarnessRouter vs Prime Agent](https://www.anchorterminal.com/compare/harnessrouter-vs-prime-agent.md)
- [HarnessRouter vs Unstoppable](https://www.anchorterminal.com/compare/harnessrouter-vs-unstoppable.md)
- [Jules vs Prime Agent](https://www.anchorterminal.com/compare/jules-vs-prime-agent.md)
- [Jules vs Unstoppable](https://www.anchorterminal.com/compare/jules-vs-unstoppable.md)
- [Junie CLI vs Prime Agent](https://www.anchorterminal.com/compare/junie-vs-prime-agent.md)
- [Junie CLI vs Unstoppable](https://www.anchorterminal.com/compare/junie-vs-unstoppable.md)
- [Kilo Code CLI vs Prime Agent](https://www.anchorterminal.com/compare/kilo-code-cli-vs-prime-agent.md)
- [Kilo Code CLI vs Unstoppable](https://www.anchorterminal.com/compare/kilo-code-cli-vs-unstoppable.md)
- [Kimi Code CLI vs Prime Agent](https://www.anchorterminal.com/compare/kimi-code-cli-vs-prime-agent.md)
- [Kimi Code CLI vs Unstoppable](https://www.anchorterminal.com/compare/kimi-code-cli-vs-unstoppable.md)
- [Kiro CLI vs Prime Agent](https://www.anchorterminal.com/compare/kiro-cli-vs-prime-agent.md)
- [Kiro CLI vs Unstoppable](https://www.anchorterminal.com/compare/kiro-cli-vs-unstoppable.md)
- [mini-swe-agent vs Prime Agent](https://www.anchorterminal.com/compare/mini-swe-agent-vs-prime-agent.md)
- [mini-swe-agent vs Unstoppable](https://www.anchorterminal.com/compare/mini-swe-agent-vs-unstoppable.md)
- [MiniMax Code vs Prime Agent](https://www.anchorterminal.com/compare/minimax-code-vs-prime-agent.md)
- [MiniMax Code vs Unstoppable](https://www.anchorterminal.com/compare/minimax-code-vs-unstoppable.md)
- [Mistral Vibe CLI vs Prime Agent](https://www.anchorterminal.com/compare/mistral-vibe-cli-vs-prime-agent.md)
- [Mistral Vibe CLI vs Unstoppable](https://www.anchorterminal.com/compare/mistral-vibe-cli-vs-unstoppable.md)
- [Muse Code vs Prime Agent](https://www.anchorterminal.com/compare/muse-code-vs-prime-agent.md)
- [Muse Code vs Unstoppable](https://www.anchorterminal.com/compare/muse-code-vs-unstoppable.md)
- [OpenAI Codex vs Prime Agent](https://www.anchorterminal.com/compare/openai-codex-vs-prime-agent.md)
- [OpenAI Codex vs Unstoppable](https://www.anchorterminal.com/compare/openai-codex-vs-unstoppable.md)
- [OpenCode vs Prime Agent](https://www.anchorterminal.com/compare/opencode-vs-prime-agent.md)
- [OpenCode vs Unstoppable](https://www.anchorterminal.com/compare/opencode-vs-unstoppable.md)
- [OpenHands vs Prime Agent](https://www.anchorterminal.com/compare/openhands-vs-prime-agent.md)
- [OpenHands vs Unstoppable](https://www.anchorterminal.com/compare/openhands-vs-unstoppable.md)
- [Prime Agent vs Qoder CLI](https://www.anchorterminal.com/compare/prime-agent-vs-qoder-cli.md)
- [Prime Agent vs Qwen Code](https://www.anchorterminal.com/compare/prime-agent-vs-qwen-code.md)
- [Prime Agent vs Mirror CLI](https://www.anchorterminal.com/compare/prime-agent-vs-reflection-mirror.md)
- [Prime Agent vs Rovo Dev CLI](https://www.anchorterminal.com/compare/prime-agent-vs-rovo-dev-cli.md)
- [Prime Agent vs Vibe-Trading](https://www.anchorterminal.com/compare/prime-agent-vs-vibe-trading.md)
- [Prime Agent vs Warp (Warp Agent CLI and the Oz Agent API)](https://www.anchorterminal.com/compare/prime-agent-vs-warp.md)
- [Qoder CLI vs Unstoppable](https://www.anchorterminal.com/compare/qoder-cli-vs-unstoppable.md)
- [Qwen Code vs Unstoppable](https://www.anchorterminal.com/compare/qwen-code-vs-unstoppable.md)
- [Mirror CLI vs Unstoppable](https://www.anchorterminal.com/compare/reflection-mirror-vs-unstoppable.md)
- [Rovo Dev CLI vs Unstoppable](https://www.anchorterminal.com/compare/rovo-dev-cli-vs-unstoppable.md)
- [CLI Manager vs Prime Agent](https://www.anchorterminal.com/compare/cli-manager-vs-prime-agent.md)
- [CLI Manager vs Unstoppable](https://www.anchorterminal.com/compare/cli-manager-vs-unstoppable.md)
- [Harness vs Prime Agent](https://www.anchorterminal.com/compare/harness-autonomous-vs-prime-agent.md)
- [Harness vs Unstoppable](https://www.anchorterminal.com/compare/harness-autonomous-vs-unstoppable.md)
- [Paperclip vs Prime Agent](https://www.anchorterminal.com/compare/paperclip-vs-prime-agent.md)
- [Paperclip vs Unstoppable](https://www.anchorterminal.com/compare/paperclip-vs-unstoppable.md)
- [Parallax vs Prime Agent](https://www.anchorterminal.com/compare/parallax-agents-vs-prime-agent.md)
- [Parallax vs Unstoppable](https://www.anchorterminal.com/compare/parallax-agents-vs-unstoppable.md)
- [Unstoppable vs Vibe-Trading](https://www.anchorterminal.com/compare/unstoppable-vs-vibe-trading.md)
- [Unstoppable vs Warp (Warp Agent CLI and the Oz Agent API)](https://www.anchorterminal.com/compare/unstoppable-vs-warp.md)

---

Query this catalogue directly over MCP: https://www.anchorterminal.com/mcp (Streamable HTTP, no key). How: https://www.anchorterminal.com/agents/#mcp