Myrlin WorkbookvsUmaDev
Generated from the two spec rows. Green marks the better value where a spec has a clear direction. Everything else is just different.
Myrlin Workbook
therealarthur · Agent harness
OSS
Panel
6.42 spec wins
- Reliability
- 5.7
- Usefulness
- 6.3
- Cost
- 8.3
- Longevity
- 5.2
“There is a demo mode, so you can watch somebody else's coding sessions before admitting you want to watch your own.”
UmaDev
umacloud · Agent harness
OSS
Panel
6.40 spec wins
- Reliability
- 6.5
- Usefulness
- 6.7
- Cost
- 6.8
- Longevity
- 5.5
“It assigns product, architecture, UI, frontend, backend, QA, security and DevOps seats, which is not a CLI flag, it is a reorganisation.”
Spec by spec
| Spec | Myrlin Workbook | UmaDev |
|---|---|---|
| Architecture | ||
| Category | Agent harness | Agent harness |
| Runs | local | local |
| Platforms | macos, linux, windows, web | macos, linux, windows |
| Context window | not documented | not documented |
| Protocols | ||
| MCP client | No | No |
| MCP server | No | No |
| Capabilities | ||
| Runs terminal commands | Yes | Yes |
| Multi-file edits | YesMyrlin calls no model itself; edits come from the Claude Code or Codex session it spawns in a terminal pane. | YesCode is generated and written by the base CLI UmaDev drives; the coordinator role plans and gates rather than editing files. |
| Git operations | YesBranch, dirty state and ahead/behind per project, worktree create and delete, and promoting an issue to a worktree plus a session. | No |
| Browser control | No | No |
| Sandboxed execution | No | No |
| Multi-agent orchestration | YesSeveral sessions across both CLIs run at once in their own worktrees; they are not coordinated with each other. | Yes |
| Headless / CI mode | No | No |
| Models | ||
| Backbone | Claude Code, Codex | Claude Code, Codex, OpenCode, Grok Build, Kimi Code |
| Bring your own model | Yes | Yes |
| Local models | No | NoAn optional local embedding model is used for retrieval only; the coding model always comes from the base CLI. |
| 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 | AGPL-3.0 | MIT |
| GitHub stars | 387 | 260 |
Which one would each critic pick
| Critic | Myrlin Workbook | UmaDev | Pick |
|---|---|---|---|
| El Juez | — | — | not enough reviews |
| El Amigo | 6.8 | 6.8 | no preference |
| El Crítico | 6.0 | 6.0 | no preference |
| El Profesor | 6.5 | 7.0 | UmaDev — Roles exchange bounded artefacts and structured verdicts, and the tool reports incomplete work as incomplete rather than presenting every run as a success. |
| La Inversora | 5.8 | 5.8 | no preference |
| La Jefa | 6.0 | 5.8 | Myrlin Workbook — A board card owning a branch, a worktree and a live session is close to how my teams already split work, and there is no console behind any of it. |
| El Hacker | 7.3 | 7.0 | Myrlin Workbook — AGPL-3.0, no telemetry, no sign-up, no cloud, and the phone layout is served over my own LAN rather than through anybody's relay. |
Picks are derived from each critic's own scores. Humans vote on matchups on the duels page.