ChatGPT-5 Best Practices: Essential Prompting Tips for Intermediate Users

Let’s be honest: Prompting hasn’t fundamentally changed with GPT‑5. Clear, concise instructions still work best. Avoid overly elaborate setups or hidden meanings—just state your intent cleanly (Forbes, Tom's Guide).

Some practical advice:

• Keep it focused: Say what you want directly.
• Use natural language: GPT‑5 responds well when prompted like you’d talk to a thoughtful assistant (AP News).
• Avoid contradictions: If you ask it to both “do X” and “don’t do X” in the same prompt, you’ll likely get muddled results (Vellum AI, wauwai.com).

GPT‑5 introduces new tuning options you can use to shape its behavior:

• Reasoning effort controls depth vs. speed—choose minimal for fast, “good enough” results, and high when you need thorough reasoning (THE DECODER, Vellum AI).
• Verbosity controls how much detail the final answer includes. Pairing low verbosity with high detail in tool or code outputs strikes the right balance (Vellum AI, CometAPI).
• Tool preambles let GPT‑5 explain its reasoning before invoking any external tools—great for transparency or debugging (Vellum AI).

These tools give you meaningful control over how GPT‑5 behaves—without needing deep technical know‑how.

GPT‑5 shines in "agentic workflows"—scenarios where it autonomously breaks down and solves complex tasks. You can nudge it toward more independence or step‑by‑step collaboration by how you frame instructions:

• Less autonomy: You can limit exploration and latency—for example, by using low or minimal reasoning effort and including context‑gathering prompts like:

  <context_gathering>
  - Search depth: very low
  - Prioritize speed over completeness—even if not fully correct.
  - Max 2 tool calls. If needed more, report progress and confirm.
  </context_gathering>

  (Vellum AI, THE DECODER)

• More autonomy: If you want GPT‑5 to stay on task until fully resolved, push for persistence:

  <persistence>
  You're an agent—keep going until the user's request is fully resolved. Don't stop or ask for clarification when uncertain—make the most reasonable assumption and proceed.
  </persistence

  (THE DECODER, OpenAI Cookbook)

  Balancing control with empowerment gives you a smoother, more effective AI experience.

GPT‑5 excels when treated like a teammate—especially in complex, multi-step tasks. Here’s how to build prompts that turn GPT‑5 into an effective collaborator:

a. Structured, Step-by-Step Engagement Works Best

Encourage GPT‑5 to think out loud and proceed in stages. This can be as simple as starting with:

“Think step‑by‑step…” or “Let's plan, then act…”
Even without those words, GPT‑5 more naturally breaks tasks into parts when given structured prompts.(Tom's Guide, Milvus)

b. Use Clear Plans and Milestones

For multi-part tasks (like planning or coding), ask GPT‑5 to first outline its approach, then confirm each step before proceeding. This mirrors human teamwork rhythm and keeps the process transparent.(Tom's Guide)

c. Control Thinking Depth

Choose between speed or depth depending on the task:

• Use fast reasoning for quick ideas.

• Opt for slower, analytical thinking when complexity matters.

  You may even manually guide GPT‑5 to the better option—don’t rely solely on its auto-selection.(Tom's Guide)

When you're not sure how to phrase a prompt, templates from professionals can be a great launchpad. They work especially well with GPT‑5’s reasoning and structure-following strengths. Here are a few formats that consistently yield strong outcomes:

1. “Expert Assistant” Template

This prompt structure is simple but powerful: ask GPT‑5 to act as an expert in a certain field, then go beyond just answering—add reasoning, creativity, and structure.

Suggested format:

Act as an expert [role e.g., assistant, analyst, strategist]. Provide a direct answer followed by a clear explanation. Include alternative solutions and a concise summary.

A widely-shared version of this prompt has earned praise for delivering consistently sharp and helpful responses, especially across formats like “Quick hit,” “Deep Dive,” and “Plan Mode” (TechRadar, Forbes).

2. Multi-Mode Reasoning Prompts

GPT‑5's new "Thinking mode" lets you fine-tune the depth of its reasoning. Use these prompts to get the most out of both quick thinking and more careful analysis:

• For depth:

  Think step-by-step. Take time for a thorough answer.

• For speed:

  Use Thinking mini mode for faster, lighter reasoning.

This helps avoid GPT‑5 automatically choosing an unsuited mode—manual selection yields better results (Tom's Guide).

3. Task-Based Prompt Examples That Work

Tom’s Guide gathered a range of prompts that consistently bring out GPT‑5’s strengths in creativity, organization, and problem-solving:

Each of these prompts taps into GPT‑5’s upgraded reasoning and creative flexibility (Tom's Guide).

Why These Templates Work Well

• They add structure—a clear role or format anchors the response.
• They guide depth—phrases like “step-by-step” help control reasoning effort.
• They play to GPT-5’s strengths—its improved storytelling, analysis, and creative synthesis are activated with these prompts.

GPT‑5 brings a new level of contextual intuition—it infers intent more proactively than earlier models. That can be both powerful and potentially misleading if you're expecting literal behavior.

What this means for prompt writers:

• Less is often more. You don’t need to overexplain your intent as you might have with earlier models. Instead, speak naturally—as though you're asking a coworker for help.

“I’m prepping for my job interview. Can you help make me sound more confident when discussing weaknesses?” 

works better than lengthy, overly formal prompts.
(Vellum AI, Tom's Guide)

• Trigger deeper analysis when needed. GPT‑5 automatically adjusts between fast, surface-level thinking and slower, more analytical reasoning—but don’t rely on this alone. Add explicit cues like “think step-by-step” when you need careful reasoning.
• Lean into natural collaboration. Write prompts that feel like back-and-forth brainstorming. GPT‑5 retains context well, so you can build on ideas iteratively:

“Let’s keep going with that concept—can you make it more humorous?”

• Control assumptions. Because GPT‑5 fills in gaps more eagerly, you must be explicit when you don’t want it to guess. Use lines like “Don’t assume tone; wait for my direction” or “Ask follow‑up questions before concluding.”

By embracing this proactive reasoning, you can prompt with clarity and creativity—without getting lost in unnecessary detail.

GPT‑5 isn’t a one-shot wonder. Its best results emerge when you refine your prompts through iteration and use few-shot examples to guide its style, structure, or output format.

Iteration Is Your Friend

Effective prompt crafting is iterative:

1. Start with a basic prompt—define intent and tone.
2. Run it and review the response: does it align with your goal?
3. Refine: tighten language, clarify structure, adjust reasoning effort or verbosity.
4. Repeat until consistent quality emerges.

This iterative tuning process is essential—not only does it reduce ambiguity, but it also helps you develop a reusable prompt "backbone" for similar tasks.
(Milvus, Fello AI)

Few-Shot Prompts Provide Strong Guidance

When you need GPT‑5 to adopt a specific format, tone, or approach, include a couple of ideal examples in your prompt:

• Provide an example or two of the style you want.
• GPT‑5 will mimic structure, tone, and logic more reliably.

This is especially valuable when output needs to follow a pattern—like a summary, critique, or creative piece.
(Tom's Guide)

Combine Few-Shot with Chain-of-Thought When Needed

For complex tasks, pair few-shot examples with chain-of-thought prompting:

• Start with an example solving a task step-by-step.
• Then ask GPT‑5 to do the same on your input.

This blend helps GPT‑5 stay structured and logical—especially when accuracy and explanation matter.
(arxiv.org, McNeece Web Design)

Summary Table: Key Takeaways

GPT‑5 brings powerful new capabilities—but it also introduces subtleties that experienced users should be aware of to avoid frustration and get the most out of the model.

Key Behaviors of GPT-5:

• Over-assuming

  GPT‑5 infers your intent from far less than previous models did—sometimes too much. This means simpler prompts can work, but vague instructions may lead it astray.

  Tip: Write prompts like you’d speak to a thoughtful colleague—clear, concise, and conversational. Keep low-stakes instructions minimal, but be direct when precision matters.(Tom's Guide)

• Variable thinking modes

  It dynamically switches between a fast, surface-level “thinking” mode and a deeper, analytical one. These mode triggers depend on your prompt style and complexity.

  Tip: If you need detail, explicitly ask it to “think step by step” or indicate “deep reasoning needed.”

• Exceptional coherence and memory

  GPT‑5 maintains conversational context longer and more reliably—making follow-ups and iterative ideas work especially well.

  Tip: Lean into iterative prompt chains—“Let’s keep going with that idea, but make it more emotional,” works smoothly.

• Overconfidence & creative fills

  The model tends to fill in ambiguity with confidence, even when it may be guessing. This can be both helpful and misleading.

  Tip: When you need control, say things like “don’t assume tone—wait for my direction” or “ask for clarification before proceeding.”

By recognizing these behavioral traits, you can structure your prompts to prompt GPT‑5’s strengths—context awareness, fluency, creativity—while avoiding misinterpretations.

GPT‑5 brings powerful new capabilities—but it also introduces subtleties that experienced users should be aware of to avoid frustration and get the most out of the model.

Key Behaviors of GPT-5:

• Over-assuming

  GPT‑5 infers your intent from far less than previous models did—sometimes too much. This means simpler prompts can work, but vague instructions may lead it astray.

  Tip: Write prompts like you’d speak to a thoughtful colleague—clear, concise, and conversational. Keep low-stakes instructions minimal, but be direct when precision matters.(Tom's Guide)

• Variable thinking modes

  It dynamically switches between a fast, surface-level “thinking” mode and a deeper, analytical one. These mode triggers depend on your prompt style and complexity.

  Tip: If you need detail, explicitly ask it to “think step by step” or indicate “deep reasoning needed.”

• Exceptional coherence and memory

  GPT‑5 maintains conversational context longer and more reliably—making follow-ups and iterative ideas work especially well.

  Tip: Lean into iterative prompt chains—“Let’s keep going with that idea, but make it more emotional,” works smoothly.

• Overconfidence & creative fills

  The model tends to fill in ambiguity with confidence, even when it may be guessing. This can be both helpful and misleading.

  Tip: When you need control, say things like “don’t assume tone—wait for my direction” or “ask for clarification before proceeding.”

By recognizing these behavioral traits, you can structure your prompts to prompt GPT‑5’s strengths—context awareness, fluency, creativity—while avoiding misinterpretations.

Getting consistently great output from GPT‑5 is a process of refinement—not one try, but many.

Iteration: The Secret Sauce

Strong prompts typically evolve through a cycle of experimentation:

1. Draft a clear, structured prompt.
2. Evaluate the response—does it meet your goals?
3. Tweak parameters (e.g., clarity, reasoning depth), test again.

This iterative approach sharpens the prompt and builds a reliable template for future tasks.
(Milvus, AP News, Vellum AI)
 

Few-Shot Prompting: Guide by Example

Demonstrate what you want by including 1–2 ideal examples in the prompt. GPT‑5 mimics structure, tone, and output format more accurately when you lead by example.
(Tom's Guide)

• Combine with chain-of-thought (e.g., “Here’s how to analyze step by step; now you do the same.”) to prompt GPT‑5 into structured reasoning.
  (Wikipedia)

Use OpenAI’s Prompt Optimizer

GPT‑5 benefits from both traditional and optimized prompting. The OpenAI Prompt Optimizer can help with:

• Eliminating contradictions in instructions
• Ensuring consistency between few-shot examples and the narrative prompt
• Refining prompt clarity and formatting
  (OpenAI Cookbook)

This tool is incredibly useful when migrating older prompts or polishing a prompt for consistent output—especially when reliability is critical.