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Glossary and references

Glossary​

TermMeaning
PromptInput that helps determine the model's next response or action; it may include more than plain text.
Prompt EngineeringDesigning and evaluating instructions, context, examples, tools, and output contracts for a target behavior.
TokenA model's text-processing unit; token boundaries do not map one-to-one to words.
Context WindowThe maximum context a model can process in one interaction/state window, subject to model and API behavior.
Zero-shotAsking for a task without in-prompt examples.
One-shotSupplying one precise example to demonstrate a required format or convention; it has limited edge-case coverage.
Few-shotSupplying a small number of examples to demonstrate a task or output convention.
Step-back PromptingEliciting or retrieving higher-level principles or criteria before applying them to a concrete task.
Chain-of-Thought (CoT)Intermediate reasoning traces. Historically, prompting models to emit such traces improved some reasoning tasks; modern reasoning models often reason internally, so production prompts should prefer verifiable summaries/evidence over demanding private reasoning.
Reasoning ModelA model family trained/configured to spend additional inference work on complex tasks, often with model-specific reasoning controls.
Self-consistencySampling multiple candidate reasoning/answer paths and aggregating them.
ReActA research/agent pattern combining model decisions, actions/tool calls, and observations.
Tree of ThoughtsA search/orchestration approach that explores and evaluates multiple candidate reasoning branches.
Structured OutputsAPI-level schema-constrained model output, typically using JSON Schema on supported models.
Function/Tool CallingAllowing a model to select and provide arguments for external functions/tools that the application executes.
MCPModel Context Protocol, used by compatible systems to expose external tools/resources through standardized servers/connectors.
RAGRetrieval-Augmented Generation: retrieve relevant external content and provide it to the model before generation.
Prompt InjectionMalicious or unintended instructions that alter model behavior; can be direct or embedded in external content.
System/Developer InstructionHigher-priority application instructions in APIs that support message-role hierarchies. Not a secure secret store.
HallucinationModel output that is unsupported, fabricated, or incorrect while being presented plausibly.
EvalA repeatable test used to measure model/prompt behavior against defined criteria.
Prompt OptimizationGenerating and selecting prompt candidates against a defined evaluation contract; it still requires held-out validation.
Multimodal PromptingDesigning a prompt and evidence contract across text, images, video, audio, or documents.
Prompt Template/VariableA versioned reusable instruction template and its typed, missing-value-aware substitution contract.
Fine-tuningUpdating a model's learned behavior using training data; distinct from supplying examples in a single prompt.
AI AgentA system in which a model can make decisions across multiple steps and use tools or external systems under an orchestration and permission model.

Key corrections from the source booklet​

The supplied v4 booklet is a strong introductory base, but this documentation makes these changes:

  • standardizes the term Prompt Engineering instead of the reversed Engineering Prompt wording;
  • treats Chain-of-Thought prompting primarily as historical/research context and avoids requiring hidden reasoning from modern reasoning models;
  • treats ReAct and Tree of Thoughts as orchestration/search patterns rather than one-line prompt tricks;
  • replaces fictional-expertise role prompts with explicit review criteria and perspective framing;
  • updates OpenAI examples around the Responses API, Structured Outputs, reasoning.effort, and max_output_tokens;
  • avoids universal temperature ranges and other model-agnostic parameter recipes;
  • makes clear that strict JSON/schema controls constrain output shape, not factual truth;
  • does not prescribe a universal few-shot example count;
  • treats BLEU/ROUGE as narrow text-overlap metrics, not default generic prompt-quality measures;
  • rejects fixed sampling or CoT temperature recipes as universal guidance;
  • adds capability, security, validation, and operational context for multimodal and code prompting;
  • distinguishes ChatGPT product memory from API conversation state;
  • states explicitly that the system prompt is not a secret or authorization boundary;
  • strengthens RAG guidance around access control, citation validation, and indirect prompt injection;
  • makes evals and regression tests part of the prompt lifecycle rather than an optional final review.

Research foundations​

The historical techniques described in this guide originate from widely cited research including:

  • Brown et al. (2020), Language Models are Few-Shot Learners.
  • Wei et al. (2022), Chain-of-Thought Prompting Elicits Reasoning in Large Language Models.
  • Kojima et al. (2022), Large Language Models are Zero-Shot Reasoners.
  • Wang et al. (2022), Self-Consistency Improves Chain of Thought Reasoning in Language Models.
  • Yao et al. (2023), ReAct: Synergizing Reasoning and Acting in Language Models.
  • Yao et al. (2023), Tree of Thoughts: Deliberate Problem Solving with Large Language Models.
  • Lewis et al. (2020), Retrieval-Augmented Generation for Knowledge-Intensive NLP Tasks.

These papers establish techniques in particular model/evaluation settings. They should not be interpreted as guarantees that the same technique improves every current model.

Current operational references​

For implementation guidance, prefer current official documentation over static tutorial parameter tables:

  • OpenAI Help Center — Prompt engineering best practices for ChatGPT.
  • OpenAI Help Center — Best practices for prompt engineering with the OpenAI API.
  • OpenAI API Reference — Responses API message roles, reasoning controls, tools, and Structured Outputs.
  • OpenAI API documentation — model-version compatibility and eval guidance.
  • OpenAI Help Center — current ChatGPT Memory documentation.
  • Google Cloud — Overview of prompting strategies and the Gemini/Vertex AI Prompting Guide.
  • Google Cloud — Vertex AI Prompt Optimizer documentation.
  • Google Cloud — multimodal prompting guidance for images, video, audio, and documents.
  • OWASP GenAI Security Project — LLM01:2025 Prompt Injection.
  • OWASP GenAI Security Project — LLM07:2025 System Prompt Leakage.
  • OWASP GenAI Security Project — current RAG/vector/embedding risk guidance.

Review date​

This documentation was technically reviewed against current public references on 2026-08-31. Provider behavior changes quickly; re-check model-specific API documentation before copying parameter names, supported values, or lifecycle dates into production code.