fxvsOpenHarness
Generated from the two spec rows. Green marks the better value where a spec has a clear direction. Everything else is just different.
fx
Vercel Labs · Terminal agent
#199OSSMCP
Panel
5.81 spec wins
- Reliability
- 5.3
- Usefulness
- 5.7
- Cost
- 7.0
- Longevity
- 5.3
“The whole agent is 7.8 MiB, which is smaller than the loading spinner on some tools it competes with.”
OpenHarness
zhijiewong · Terminal agent
#209OSSMCP
Panel
5.73 spec wins
- Reliability
- 5.5
- Usefulness
- 5.8
- Cost
- 7.7
- Longevity
- 3.8
“It has agent roles, so the same model can now let you down under several different job titles.”
Spec by spec
| Spec | fx | OpenHarness |
|---|---|---|
| Architecture | ||
| Category | Terminal agent | Terminal agent |
| Runs | local | local |
| Platforms | macos, linux | macos, linux |
| Context window | not documented | not documented |
| Protocols | ||
| MCP client | Yes | Yes |
| MCP server | No | No |
| Capabilities | ||
| Runs terminal commands | Yes | Yes |
| Multi-file edits | Yes | Yes |
| Git operations | No | Yes |
| Browser control | No | No |
| Sandboxed execution | No | No |
| Multi-agent orchestration | Yes | Yes |
| Headless / CI mode | No | Yes |
| Models | ||
| Backbone | Vercel AI Gateway models, OpenAI, Grok | Ollama, OpenAI, any LLM |
| Bring your own model | Yes | Yes |
| Local models | No | Yes |
| Cost | ||
| Pricing model | byok | byok |
| Starts at | $0/mo | $0/mo |
| Free tier | Yes | Yes |
| Bring your own key | Yes | Yes |
| Openness | ||
| Open source | Yes | Yes |
| License | Apache-2.0 | MIT |
| GitHub stars | 3,250 | 102 |
Which one would each critic pick
| Critic | fx | OpenHarness | Pick |
|---|---|---|---|
| El Juez | — | — | not enough reviews |
| El Amigo | 6.0 | 6.0 | no preference |
| El Crítico | 5.3 | 5.5 | OpenHarness — Forty-four tools ship in one agent and the only boundary described is a set of permission modes, with no isolation recorded anywhere in the row. |
| El Profesor | 6.3 | 6.0 | fx — Output stays shell-shaped rather than a full-screen interface, and it reads a competitor-compatible tool configuration file, which makes the setup portable between agents. |
| La Inversora | 5.8 | 4.5 | fx — A labs project rather than a product, with billing that runs through the parent's inference routing service, so the free binary is the metered path in. |
| La Jefa | 4.8 | 5.3 | OpenHarness — Free across sixty desks, and an official Python SDK driving the same binary from pipelines is the part that would let me measure it rather than hear about it. |
| El Hacker | 7.0 | 7.0 | no preference |
Picks are derived from each critic's own scores. Humans vote on matchups on the duels page.