Placement Decision: Workflow vs Activity vs Worker vs Client

When to use

Use when the user describes logic and asks where it belongs, or when code boundaries are unclear.

Decision rules

• •Workflow: orchestration, durable state, timers, waiting, child workflows, calling activities.
• •Activity: side effects, IO (DB/network/files), CPU-heavy non-deterministic work, external services.
• •Worker: registrations, task queues, interceptors, converters/codecs, DI/host configuration.
• •Client: start/signal/query/update workflows; idempotency keys; request shaping.

Required output

Return:

• •A 4-row table (Workflow/Activity/Worker/Client) with Yes/No, Why, and Minimal snippet
• •A single “recommended boundary” diagram in text (e.g., bullets)

Guardrails

• •If anything touches time/randomness/IO: default to Activity unless proven deterministic in workflow.