Performance bottleneck hunt
Model notes: Give real measurements if you have them
Fill in the variables (optional — they're inserted live below):
This is slow: {{what_is_slow}} (currently ~{{current_time}}, target {{target_time}}).
Code / query:
```
{{code}}
```
1. Point out the likely hotspots and estimate their cost (big-O or I/O round trips).
2. Tell me how to measure before changing anything (profiler, EXPLAIN, timing logs) for {{stack}}.
3. Suggest fixes in order of effort vs impact. Don't sacrifice readability for micro-optimisations.
How to use it
- Fill the variables above, or replace each
{{variable}}after pasting. - Paste into your AI tool (ChatGPT, Claude, Gemini, Cursor, Claude Code, or a local model in Ollama/LM Studio).
- Review the output. Models make mistakes, especially with facts, numbers and code.
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More Debugging prompts
Debugging
Root-cause a bug, don't patch symptoms
Strong reasoning model recommended
Variables: expectedactualstepserror_outputcode_or_files
Help me find the root cause of this bug. Don't propose a fix until we've confirmed the cause.
What I expected: {{expected}}
What happened: {{actual}}
Steps to reproduce: {{steps}}
Error / logs:
```
{{error_output}}
```
Relevant code: {{code_or_files}}
Process:
1. List 3-5 plausible hypotheses, ranked by likelihood, each with the evidence for and against.
2. For the top hypothesis, give me the single quickest experiment (log line, breakpoint, command) to confirm or rule it out.
3. Wait for my result before continuing. Help me find the root cause of this bug. Don't propose a fix until we've confirmed the cause.
What I expected: {{expected}}
What happened: {{actual}}
Steps to reproduce: {{steps}}
Error / logs:
```
{{error_output}}
```
Relevant code: {{code_or_files}}
Process:
1. List 3-5 plausible hypotheses, ranked by likelihood, each with the evidence for and against.
2. For the top hypothesis, give me the single quickest experiment (log line, breakpoint, command) to confirm or rule it out.
3. Wait for my result before continuing.
Open & fill variables → Debugging
Explain this error like I'm new to the stack
Fine on small local models (7B+)
Variables: error_messagelanguage_or_framework
Explain this error message in plain English:
```
{{error_message}}
```
Context: I'm using {{language_or_framework}}.
Tell me: what it literally means, the 3 most common causes, how to check which one applies to me, and the usual fix for each. Keep it under 250 words. Explain this error message in plain English:
```
{{error_message}}
```
Context: I'm using {{language_or_framework}}.
Tell me: what it literally means, the 3 most common causes, how to check which one applies to me, and the usual fix for each. Keep it under 250 words.
Open & fill variables → Debugging
Stack trace triage
Paste the full trace, not a screenshot
Variables: languagestack_trace
Here is a stack trace from {{language}}:
```
{{stack_trace}}
```
1. Identify the frame where the error originates in MY code (not library code) and explain why that's the likely culprit.
2. Explain the chain of calls that led there.
3. List what information is missing to be sure (variable values, inputs).
4. Suggest the exact log statements to add, with file and line, to capture that information. Here is a stack trace from {{language}}:
```
{{stack_trace}}
```
1. Identify the frame where the error originates in MY code (not library code) and explain why that's the likely culprit.
2. Explain the chain of calls that led there.
3. List what information is missing to be sure (variable values, inputs).
4. Suggest the exact log statements to add, with file and line, to capture that information.
Open & fill variables → New prompts every week
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