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📚 Prompt engineering guides

Fundamentals

Prompt engineering best practicesDesigning system promptsFew-shot prompting

Reliability

Structured outputs & JSONReducing hallucinationsEvaluating prompts

Advanced & trending

Reasoning models & chain-of-thought

Production

Model-agnostic, portable prompts

More

API docs Free tools

Free · prompt engineering

Prompt engineering guides

Practical, no-fluff guides to writing prompts that work — and keep working. From the fundamentals to structured outputs, evals, reasoning models, and running prompts in production.

Fundamentals

Prompt engineering best practices

The core habits: be specific, give structure, show examples, and constrain the output.

Designing system prompts

Set role, rules, and format once so every call behaves consistently.

Few-shot prompting

Teach the pattern with examples — how many, how to pick them, and when to stop.

Reliability

Structured outputs & JSON

Get clean, parseable JSON every time — schemas, validation, and repair.

Reducing hallucinations

Ground the model, let it say 'I don't know', and check claims.

Evaluating prompts

Turn 'looks fine' into pass/fail checks that catch regressions.

Advanced & trending

Reasoning models & chain-of-thought

When to prompt for reasoning — and why o-series models change the rules.

Production

Model-agnostic, portable prompts

Write prompts that run on any model, so switching is a config change.

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