write

  # them in step with the two `const:` entries above.
  fs:
    read: ["./README.md"]     # SLOT: same path as const.source
    write: ["./output.md"]    # SLOT: same path as const.destination

tasks:
  gather:
    invoke:                         # SLOT: the fact source · nika:read / nika:fetch / exec
      tool: "nika:read"
      args: { path: "${{ const.source }}" }