Prompt engineering
Use XML tags to structure your prompts
While these tips apply broadly to all Claude models, you can find prompting tips specific to extended thinking models here.
XML tip: Use tags like
<instructions>, <example>, and <formatting> to clearly separate different parts of your prompt. This prevents Claude from mixing up instructions with examples or context.Why use XML tags?
- Clarity: Clearly separate different parts of your prompt and ensure your prompt is well structured.
- Accuracy: Reduce errors caused by Claude misinterpreting parts of your prompt.
- Flexibility: Easily find, add, remove, or modify parts of your prompt without rewriting everything.
- Parseability: Having Claude use XML tags in its output makes it easier to extract specific parts of its response by post-processing.
There are no canonical “best” XML tags that Claude has been trained with in particular, although we recommend that your tag names make sense with the information they surround.
Tagging best practices
- Be consistent: Use the same tag names throughout your prompts, and refer to those tag names when talking about the content (e.g,
Using the contract in <contract> tags...). - Nest tags: You should nest tags
<outer><inner></inner></outer>for hierarchical content.
Power user tip: Combine XML tags with other techniques like multishot prompting (
<examples>) or chain of thought (<thinking>, <answer>). This creates super-structured, high-performance prompts.Examples
Example: Generating financial reports
Example: Generating financial reports
Without XML tags, Claude misunderstands the task and generates a report that doesn’t match the required structure or tone. After substitution, there is also a chance that Claude misunderstands where one section (like the the Q1 report example) stops and another begins.
| Role | No XML Tags | With XML Tags |
|---|---|---|
| User | You’re a financial analyst at AcmeCorp. Generate a Q2 financial report for our investors. Include sections on Revenue Growth, Profit Margins, and Cash Flow, like with this example from last year: {{Q1_REPORT}}. Use data points from this spreadsheet: {{SPREADSHEET_DATA}}. The report should be extremely concise, to the point, professional, and in list format. It should and highlight both strengths and areas for improvement. | You’re a financial analyst at AcmeCorp. Generate a Q2 financial report for our investors. AcmeCorp is a B2B SaaS company. Our investors value transparency and actionable insights. Use this data for your report:<data>{{SPREADSHEET_DATA}}</data> <instructions> 1. Include sections: Revenue Growth, Profit Margins, Cash Flow. 2. Highlight strengths and areas for improvement. </instructions> Make your tone concise and professional. Follow this structure: <formatting_example>{{Q1_REPORT}}</formatting_example> |
| Assistant | Q2 Financial Report for AcmeCorp Investors Dear Valued Investors, I am pleased to present our Q2 financial report, showcasing AcmeCorp’s continued growth and resilience in the B2B SaaS market. 1. Revenue Growth: Our Q2 revenue reached $15.2M, a 22% YoY increase. This growth is primarily driven by a 30% expansion in our enterprise client base. However, our SMB segment saw a slight decline of 5%, which we aim to address through targeted marketing initiatives in Q3. 2. Profit Margins: Gross margin improved to 72% (up 3% from Q1) due to infrastructure optimizations. EBITDA margin, however, dipped to 18% (down 2%) as we invested heavily in R&D for our upcoming AI-driven features. 3. Cash Flow: Operating cash flow remains strong at $4.1M. Our cash reserves stand at $28M, providing a 15-month runway at current burn rate. We did see a 20% increase in customer acquisition costs, which we’re addressing through more efficient sales strategies. In summary, AcmeCorp’s core financials remain robust. We’re balancing growth investments with prudent cash management. Our focus for Q3 will be revitalizing SMB growth and optimizing sales efficiency. Thank you for your continued trust. Sincerely, CFO, AcmeCorp | Q2 Financial Report for AcmeCorp Investors</output> Revenue Growth: - Q2 revenue: $15.2M (22% YoY ↑) - Enterprise clients: 30% ↑ - SMB segment: 5% ↓ Action: Targeted Q3 marketing Profit Margins: - Gross margin: 72% (3% ↑ from Q1) Reason: Infrastructure optimizations - EBITDA margin: 18% (2% ↓) Reason: R&D investment in AI features Cash Flow: - Operating cash flow: $4.1M (strong) - Cash reserves: $28M (15-month runway) - Customer acquisition cost: 20% ↑ Action: Optimize sales strategies Outlook: - Core financials: Robust - Q3 focus: Revitalize SMB, optimize sales Management remains committed to balancing growth investments with financial discipline. |
Example: Legal contract analysis
Example: Legal contract analysis
Without XML tags, Claude’s analysis is disorganized and misses key points. With tags, it provides a structured, thorough analysis that a legal team can act on.
| Role | No XML Tags | With XML Tags |
|---|---|---|
| User | Analyze this software licensing agreement for potential risks and liabilities: {{CONTRACT}}. Focus on indemnification, limitation of liability, and IP ownership clauses. Also, note any unusual or concerning terms. Here’s our standard contract for reference: {{STANDARD_CONTRACT}}. Give a summary of findings and recommendations for our legal team. | Analyze this software licensing agreement for legal risks and liabilities. We’re a multinational enterprise considering this agreement for our core data infrastructure. <agreement> {{CONTRACT}}</agreement> This is our standard contract for reference: <standard_contract>{{STANDARD_CONTRACT}}</standard_contract> <instructions> 1. Analyze these clauses: - Indemnification - Limitation of liability - IP ownership 2. Note unusual or concerning terms. 3. Compare to our standard contract. 4. Summarize findings in <findings> tags. 5. List actionable recommendations in <recommendations> tags.</instructions> |
| Assistant | The provided software licensing agreement presents several concerning aspects. The indemnification clause is overly broad, potentially exposing us to significant liabilities. The limitation of liability section caps damages at a mere $500, which is inadequate for our enterprise-level usage. Regarding IP, the agreement grants the vendor joint ownership of any modifications or integrations we create. In summary, this agreement is not in our best interest. It exposes us to undue risk, limits our recourse in case of failures, and compromises our intellectual property rights. I recommend renegotiating these terms or seeking alternative vendors. | <findings> 1. Indemnification (Clause 8): - Issue: Overly broad. We indemnify vendor against “any and all claims” arising from our use. - Risk: Could hold us liable even for vendor’s negligence or product defects. - Deviation: Our standard limits indemnity to claims arising from our violation of agreement. 2. Limitation of Liability (Clause 9): - Issue: Caps all damages at $500, including direct damages. - Risk: Grossly inadequate for enterprise use. A critical failure could cost millions. - Deviation: Our standard allows for direct damages up to 12 months of fees paid. 3. IP Ownership (Clause 12): - Issue: Grants vendor joint ownership of our modifications/integrations. - Risk: Vendor could use or sell our proprietary algorithms or data insights. - Deviation: Our standard retains full ownership of our work. 4. Unusual Terms: - Clause 5.3: Vendor can use our usage data for “any purpose.” - Clause 7.2: Vendor can terminate for “convenience” with only 7 days’ notice. - Clause 11: No warranties of any kind, even for basic merchantability. </findings> <recommendations> 1. Reject this agreement. Risks far outweigh benefits for an enterprise. 2. Counter-propose: - Indemnification: Limit to claims arising from our violation of agreement. - Liability: Cap at 12 months’ fees for direct damages; negotiate for indirect. - IP: Full ownership of our modifications/integrations. - Data Use: Restrict to service improvement only. - Termination: Minimum 90 days’ notice; only for cause. - Warranties: Demand basic merchantability and fitness for purpose. 3. If vendor refuses, explore alternative providers or in-house solutions. 4. Engage legal counsel for contract negotiation given high stakes. </recommendations> |
Prompt library
Get inspired by a curated selection of prompts for various tasks and use cases.
GitHub prompting tutorial
An example-filled tutorial that covers the prompt engineering concepts found in our docs.
Google Sheets prompting tutorial
A lighter weight version of our prompt engineering tutorial via an interactive spreadsheet.