System1 Agents

It is an agent harness where the decision model occupies the model slot of a stock openJiuwen agent. On a decision turn it receives state and options and answers with one of them, while planning, typed values, and the final answer still go to a chat model inside the same agent. Any model with that interface fits, which is why Laya and an in-process Cua model are options too.

Each row is the same agent with one variable changed and wall-clock timing, Jev on one side and a chat model on the other. Two caveats come from the source itself: the ALFWorld chat-model cost is an estimate because that run recorded no cost, and the README still carries an unfilled HTML placeholder asking for the name of the chat model behind those columns. docs/benchmarks.md holds the remaining runs.

They stay with the chat model. The builder skill probes the task with 8 to 12 hand-written decisions before it writes any code, and it stops when the task needs deduction or arithmetic. The skill is written to hand over page tasks, games, and one-off selections, and docs/skills.md covers what to delegate and what to keep.

For the live model paths, yes: TYPESAFE_API_KEY from the TypeSafe console, or OPENROUTER_API_KEY. The cheapest way in is uv sync --extra cua with --model cua, which answers in process with no key at all. s1a decide prints one JSON object with the choice, a probability per option, confidence, and milliseconds.

From Claude Code or Codex run npx skills add ThinkFlowLab/system1-agents, or add the plugin for the browser subagent and MCP server. From the command line, clone the repository and run uv sync, then uv run s1a decide, or uv run s1a run <agent>. The project asks for Python 3.11+.

Jev, Laya or Cua-S1 Nano out of the box, and OmniJev for screen-reading tasks via --model omnijev, which sends the browser agents a screenshot at each step. Without any key, --model cua answers in process.

allrecipes (browser use on the live site), flights (a Google Flights search over Playwright MCP), desktop (computer use through Cua Driver), ticket_router (30 labelled tickets to five queues), and games including 2048, Millionaire and Blackjack. The code is Apache-2.0.