Sequential research is slow. The agent fetches three sources one by one, then a fourth, then summarises. Most of that time is network wait, not work, and a serial loop wastes it.
Independent reads or computations whose results combine at the end. Multi-source research, parallel API checks, multi-region pings, batch document summarisation.
When step N depends on step N-1's output. Parallelism adds nothing if the data is causally chained.
Drop this into an app.yaml. Adjust the credential refs and module names to fit your existing setup.
1modules:2 web: {}3 agent_spawn: {}45agents:6 - id: lead7 modules: [{agent_spawn: [Agent]}]8 brain: { model: claude-sonnet-4-6, credential: anthropic_main }9 system_prompt: |10 For research tasks, dispatch THREE explorer sub-agents in parallel,11 one per source domain (news, academic, vendor). Then call12 Agent(agent_ids=[id1,id2,id3]) to wait for all, then synthesize.1314 - id: explorer15 role: specialist16 modules: [{web: [search, fetch]}]17 brain: { model: claude-haiku-4-5, credential: anthropic_main }18 system_prompt: "Find 3-5 sources for the topic. Return facts and citations."Walking through the YAML one block at a time so the design is clear, not memorised.
Three Agent(prompt='research news angle'), Agent(prompt='research academic angle'), Agent(prompt='research vendor angle') calls go out in the same model response. The runtime executes them concurrently via asyncio.gather.
Background mode is the default. The coordinator gets three IDs back without waiting, ready to plan the join.
Agent(agent_ids=[id1, id2, id3]) blocks until all three complete or hit their per-agent deadline. The coordinator gets a list of results in order.
The lead's next turn writes the final answer using all three results. Total latency is max(t1, t2, t3) plus a small synthesis step, not their sum.
The pattern above is not the only answer. Here is when something else is the right call.
Easier for the model to reason about, slower. Good when each step's output narrows the next query.
Run one explorer multiple times in sequence with different prompts. Cheaper to reason about, sequential cost.
Engineering notes from the Digitorn team. No marketing, no launch announcements, no "10 prompts that will change your life". Just the things we write that we'd want to read.