Agent Script block types
Key Takeaway
An Agent Script file is split into blocks that each do one job. At minimum, an agent needs the system, config and start_agent blocks.
Agent Script is the language behind every agent in Agentforce Builder. A script file is split into blocks, which are top-level sections that each do one job. For example, blocks hold the global instructions, the agent settings, the variables, the entry point or a subagent. When you know the block types, you know where each part of an agent's behavior lives and where to change it.
How an Agent Script file is built
Agent Script is built from properties written as key: value. The top-level properties are called blocks, and they appear in a set order.
The blocks work like a declarative language: you declare what the agent is and what it has, without spelling out a step-by-step flow.
Agent Script is whitespace-sensitive, like Python or YAML, so indentation shows which properties belong to which block. Pick either spaces or tabs and use that method throughout, because mixing them causes parsing errors.