337 posts · Page 7 of 29. ← Blog
How to broadcast one input to several executors in parallel and join their answers with a barrier — the core workflow graph primitives, with no LLM in the way.
A start executor broadcasts a question to two experts via a fan-out edge; a fan-in barrier edge joins both answers before the aggregator yields output.
Agents as graph nodes: switch-case routing, fan-out/fan-in, and mixing plain functions with agent steps in one workflow.
Agents are just workflow executors: switch-case routing, fan-out/fan-in concurrency, and mixing plain function nodes with agent nodes in one graph.
How a plain function becomes a callable tool, how ToolContext reaches session state, and how long-running tools pause a run for a human.
Tools give agents capabilities: a plain function becomes a tool with its signature as the schema, plus ToolContext, built-in tools, and long-running/human-in-the-loop tools across Python and Go.
How to pause a workflow to ask a human, checkpoint every super-step, then rewind the whole graph to a saved checkpoint and replay.
A RequestPort pauses to ask a human for a guess while every super-step is checkpointed, then RestoreCheckpoint rewinds the whole graph including tries state.
The graph model underneath every multi-agent app: executors as nodes, edges as data flow, and typed events streaming out as it runs.
The MAF workflow model in Python: executors as nodes, edges as data flow, switch-case routing, and typed streaming events - learned model-free.
How one agent routes work to specialists — and why the description field is the most important string you write.
Agent hierarchies and LLM-driven delegation: sub_agents, how the description field drives auto-transfer, and coordinator/dispatcher patterns — contrasted with deterministic workflow agents.
How to snapshot a workflow after every super-step, then rewind the same live run to an earlier checkpoint and replay from it.
Same guess-the-number graph, but RestoreCheckpoint rewinds the live run to the 6th snapshot and replays forward — no fresh workflow instance needed.
Turn agent runs into OpenTelemetry spans, block prompt injection with information-flow control, and swap model providers behind one Agent API.
Turn MAF agent runs into OpenTelemetry spans, block prompt injection with information-flow control, and swap model providers behind one Agent API.
When you want fixed control flow, don't ask the model — wire it yourself.
Sequential, Parallel, and Loop agents compose sub-agents in fixed patterns — deterministic orchestration where you, not the model, decide control flow, with state flowing between steps.
How to snapshot a running workflow at every super-step, then throw the instance away and rebuild a fresh workflow that resumes from a saved checkpoint.
A cyclic guess-the-number workflow snapshots state each super-step, then a brand-new workflow instance is rehydrated from a checkpoint via ResumeStreaming.
Wrapping an agent run with async seams that log, time, guard, and short-circuit — without touching the agent's logic.
Wrapping an MAF agent run in Python with async middleware seams — timing, logging, and a guardrail that short-circuits a tool call before it runs.
description, instruction, generation params, and structured output — the dials on almost every agent you'll build
The four knobs on almost every ADK agent: description (for delegation), instruction with {state} templating, generation params, and structured output — Python Pydantic model vs Go genai.Schema.