Guards

Guards are live circuit breakers that monitor an agent during execution. While gates check after a step finishes, guards watch in real-time and kill the agent immediately if a condition is met.

Declaring guards

- name: impl
  type: code
  run:
    agent: claude-haiku
    guard:
      max_turns: 30
      max_budget: 2.00
  gate: [compile, test]

Available guards

Guard	Description
`max_turns`	Kill if turns exceed a threshold
`max_budget`	Kill if estimated cost exceeds a dollar amount
`max_tokens`	Kill if tokens consumed exceed a threshold
`max_time`	Kill if wall-clock duration exceeds a threshold. Alias: `timeout`
`no_write`	Kill if the agent writes files outside `.gump/out/`

no_write is implicitly true for split and validate step types. Override with guard: { no_write: false } if needed. timeout is an alias for max_time — if both are present, it’s a parsing error.

What happens when a guard triggers

The agent is killed immediately
The worktree is reset to the pre-step state (mutations undone)
Partial metrics are collected (tokens spent, cost so far, turns completed)
The gate runs (it will fail)
Retry applies — same flow as a gate failure

A guard_triggered event is emitted in the ledger with the guard name, reason, and partial metrics.

Guards are reactive, not preventive

Guards react to agent behavior by parsing the NDJSON stream. There’s a small delay between the agent acting and the guard detecting it. File writes are caught and reverted via worktree reset. Network calls or other side effects outside the worktree cannot be undone.

Guards vs Gates

	Gates	Guards
When	After the step finishes	During execution
What	Compile, test, lint, schema, validators	Turn count, cost, tokens, time, file writes
Mechanism	Shell commands, file checks, agent workflows	Stream parsing, process kill
On failure	Retry applies	Retry applies (via gate fail)
LLM involved	Only for workflow validators	Never

Overview

Getting Started

Writing Workflows

Orchestration

Execution & Data

Agents

Reference

Guards

Guards

Declaring guards

Available guards

What happens when a guard triggers

Guards are reactive, not preventive

Guards vs Gates

​Guards

​Declaring guards

​Available guards

​What happens when a guard triggers

​Guards are reactive, not preventive

​Guards vs Gates

Guards

Declaring guards

Available guards

What happens when a guard triggers

Guards are reactive, not preventive

Guards vs Gates