Agent Patterns
The techniques behind the jobs. Every page here answers the same three questions: how it works, when it is worth the cost, and how it fails.
23 patterns
These are the techniques the job pages keep reaching for. Each one has a demo, the cases where it pays, the cases where it is a waste, and what it costs in tokens, latency, and complexity.
Reflection
The agent criticises its own output before anyone sees it, against fixed criteria.
Sampling and voting
Run the same step several times and take the majority, for the steps that matter.
Verification
Check the answer against the tool results before it reaches anyone.
Supervisor and workers
One agent owns the goal and hands narrow tasks to specialists.
Debate and judging
Two agents argue opposite sides, a third decides.
Shared state
Agents read and write one shared workspace instead of messaging each other.
Human in the loop
Design the approval step so a person can actually judge it in seconds.
Budgets and limits
Steps, time, tool calls, and money: every agent needs all four capped.
Retries and idempotency
Retry the read, never the write, unless the write is idempotent.
Caching
The same question twice should not cost twice, and often should not be asked twice.
Cost control
Where agent money actually goes, and the four levers that move it.
Tracing and logging
If you cannot replay a run, you cannot fix it.
Evaluation harness
A frozen set of tasks with expected outcomes, run on every change.
Structured output
Ask for JSON with a schema, validate it, and repair once.
Retrieval for agents
Retrieval as a tool the agent chooses, not a step that always runs.
Choosing a model
Pick per step, not per system, and let the cheap steps be cheap.
Prompts for agents
An agent's system prompt is an operating manual, not a personality.
Long-running agents
Work that takes hours needs checkpoints, resumption, and a way to be cancelled.
Computer-use agents
Agents that click and type in a real interface, for systems with no API.
Voice agents
Speech adds latency, ambiguity, and no undo. Design for interruption.
Tool protocols
How agents connect to tools they did not ship with, safely.
Failure modes
The eleven ways agents fail, and which check catches each one.
Rolling out an agent
Shadow, assist, approve, auto: the four stages and what to measure at each.
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