Chain

Chain runs a non-empty list of agents, tools, or nested workflows in order. Each step receives the preceding step's output unless a slot supplies an input function.

import { Chain } from "@nylorun/agents/define";

export const report = Chain({
  id: "report",
  steps: [
    researcher,
    {
      run: analyst,
      input: ({ results }) =>
        `Summarize: ${results.researcher.findings}`,
    },
    {
      run: publish,
      input: ({ value }) => ({ summary: value.summary }),
    },
  ],
});

Values and results

• value is the immediately preceding step's output.
• results contains earlier outputs keyed by step id.
• input is the original workflow input.

A direct step keeps its runnable id. Set id on a slot when the same runnable appears more than once or when you want a stable result key:

{
  id: "final-review",
  run: reviewer,
  input: ({ value, input, results }) => ({ value, input, results }),
}

The chain output is the final step's output. Step ids must be unique among siblings. Runtime checkpoints every node boundary, so a resumed chain does not repeat completed effects.

See the shipped chain example, then learn how to route with Switch.